This tutorial is absolutely brilliant and it helped me immensely rebuilding the carbs on my 250 and 400. They both run so much better with a cleaning and proper understanding of carb assembly. Thank you!

Wow, you really know what you're talking about. I wish you were close so I could take my XR to your care. Thank you

Brother, this was so helpful. I just bought a 03 xr400r and I got her running based off this tutorial. MUCH appreciated bud

Thanks for sharing your knowledge. I learned about five more things to check the next time I clean my xr250 carb. I found your channel after reading on thumper talk.

So helpful!! Rebuilt my carb as per your video… My XR400 runs like a dream.. Thanks Buddy 😀

Best tutorial ever. Very detailed and simple. I like your tip using "Comet" Nice work!

Cheers Trailryder42 👍😏 really nice patient and informative run through with no fluff... thanks for the Ajax/comet tip too!

Ive been looking for somenthing like these too much time !!!! Very helpful video ... thanks

Wow, outstanding tutorial. My carb was leaking fuel. I used your video to take it apart, replaced all of the o'rings and did other house keeping things while I was in there. Like bend the little tabs on the white umbrella looking thingy. Got it back together tonight and it runs like a champ and no leaks. Thank you so much. Great editing too.

@Trailryder42

5 жыл бұрын

Cool. Glad to hear.

Just wanted to say thanks for your video! I live in Denver and I have an XR 400 r that I bought from somebody it’s in really great shape but it had an issue with the carb but after watching your video I figured out what it was and fixed it, somebody had-the hole by the needle covered they had the linkage turned the wrong way! Needless to say new subscriber here !

@Trailryder42

Жыл бұрын

Glad to hear it. Yeah, that hole being covered is something you'd never figure out if you didn't know it was there, and even if you did, most people wouldn't give it second thought.

Hey thanks man i got my first bike 2001 xr400r 6 months ago last weekend i ran into a deep mud whole and fludded it all i recently had to clean it all out and i cleaned the card and people DO NOT LEAVE THE SPRING OR O RING out of your fuel screw i just had to order a carb rebuild kit just for that without the o ring and spring it will vibrate out and i lost mine thank u for showing me how it goes in!!!!!

Great great video mate i learned so much in that 20 minutes!

Thank you very much. Clear explanation. I have an XR600R. the carb of the XR400 is very similar to mine.

Thanks for sharing this video, following it helped solve my leaking carb.

This was super helpful! Thank you Trailryder.

This had helped me heaps,your the man🍀

Thanks Trailryder42, I adjusted the minimum to 14mm-15mm and the max to 19mm-20mm, the bike now runs amazing, i can now sit up at 12 o clock in 3rd, so smooth, thanks again :)

I found your XR400 carburetor tutorial a couple of weeks ago. My 400 has been to the dealer multiple times for carburetor issues. Following your instructions I found numerous problems that had not been addressed over the years and the wrong assembly of internal parts. I'm looking forward to getting the bike back together and having the internals the way they are supposed to be. Thanks for posting this tutorial.

@Trailryder42

3 жыл бұрын

Thanks Yote. Hope this tutorial gets your bike running for you.

I ve done the same thing on xr 250r...your video help me a lot ..thank you very much

I just bought a XR500, this help me alot. thanks

Thanks Trailryder42....XR400r is jumpable now !!!! CHEEEEHUUUU .Cheers

Thanks TrailRyder. Very helpful info!

Very informative and easy to follow. Thank you

Greatly appreciated! I've got a crankcase full of gas and I know it's from a dirty carb. Time to clean it.

I did this years ago when I had my XR. As the guy says there is a bit of performance gain with this, I actually found it easier to start, if cold would just too bike on its side to get extra fuel in. Recommend doing this 100%.

Darren, A lot of people pull their slosh baffle because they have a hard time keeping it from coming off, finding it loose in the bowl. I think in the video I tell what I did to mine to fix that. The baffle is there to provide a uniform fuel level in the bowl and prevent fuel agitation. I guess if you ride nothing but fire roads and street, you can eliminate it, but if your ride bumpy, technical stuff, I'd keep it.

This video helped me a lot. Thank you.

This is great detaied information. Thank you so much!

Thank you sir! Excellent instruction

Great vid....thanks for sharing.

Amazon sells a set of JIS Screwdrivers for as little at $17. All Japanese built motorcycles use Japanese Industrial Standard (JIS) cross tip screws which are slightly different from "Phillips" screws. The tell tale difference is a JIS screw will have a round indent next to the cross. A proper JIS driver will fit the screw much better than a phillips driver and will almost never strip the head.

Great video. Thank you

awesome video ....very helpful info

Great tutorial. Thank you. Braaap

Great video. Thanks

thank you very much!

Bought a 2002 Xr400r, at the start of the year, which was a little rough visually but was running and starting well. I did an oil and filter change then rode it for about 700km just commuting and it was going well. I then went on a 200km ride with mates where 70km in I came off on a low speed corner and blew out my left knee. I then had to ride home for 130km. On that journey I had to stop 3 times due to pain but was afraid to stop the engine for fear of not being able to start it with a buggered knee. The bike then sat for 2 mths and when I tried to start it it wouldn't. I then pulled the carb and found a nasty scaly green build up inside which I cleaned out and rebuilt the carb, following your tutorial, with new jets etc. I used 60 pilot and 160 main as it has the Gordon mods, it had a 55 and 162 in it, and set the floats as you describe here adjusted the valves but I cannot get it to start it will pop and try to start but I can't get her to run. Not sure what to do other than a pumper but don't want to blow the money if it doesn't work.

@Trailryder42

11 ай бұрын

Did you also remove the fuel mixture screw, it's spring, washer and oring and blast that passage with cleaner? That is the starting circuit. If it's clogged it will not start. Be careful removing the screw so that you don't lose the other parts. If you're doing it with the carb on the bike, put a rag under the carb to catch anything that falls out. The oring will often stay up in there. DO NOT blow it out with compressed air, as you risk losing it. I'll use a piece of small safety wire or something like a bread tie, shape the end like a hook and fish it out. Be sure to count the number of turns out the screw was set to originally before you remove it, so you can return it to that setting afterward. When you set the valves, did you need to adjust any of them? If they needed adjusting more than .001" or 2, be sure you had set the engine to TDC on the "compression" stroke. If you were set at TDC on the exhaust stroke and made any adjustments, the valves are now set wrong and chances are the engine will not start and run. Does your bike still have a working manual decompression lever on the handlebars? Learn to use that as an easy way to restart an engine during a rolling restart. Comes in handy for just such a situation as having a bum leg for kick starting. The procedure is similar to putting the bike in 2nd or 3rd gear, getting rolling and dumping the clutch, but is a much smoother restart when you add holding the decomp lever. You release the clutch first, then the decomp lever. The engine/transmission doesn't try to lock up when holding the decomp because you're releasing compression by holding the decomp lever. The bike continues to roll. Then you release the decomp lever, compression is restored and the bike easily restarts. This restart method can be done in a much shorter run distance too when you release the decomp immediately after dumping the clutch and the transmission gets turning.

The reason the ‘Phillips head’ screws strip out so easy is because people use Phillips drivers on them, they are actually Japanese Industrial Standard screws. Get yourself a set of JIS drivers and you will never have this problem again. One of the best things to have in your kit if you own a Japanese motorcycle.

Good job thanks

This helped me tremendously. thank you so much for your detail and insight. I have an 04 xr400 that hasn't started in about a year and a buddy asked me to get it running for him. well I got it to fire off today. but it's pushing more gas from the over flow line off the bowl when running? any other tips you have would be fantastic thanks again

@JakeMadz

2 жыл бұрын

I have the same issue, the float doesn't seem to be shutting the fuel off from sitting in the bowl, spent a lot of money saving the carb looked at last week!! You can get a rebuild kit on ebay for less than 10 pounds. Hope this helps 🙂

How essential is the slosh baffle because I stripped my carb yesterday and there wasn't one on there. Great vid by the way :)

I also have the xrs only choke plate installed and now my one kick bike is more like 10! Would i adjust the fuel screw to remedy this? I live in Mi. So a cold start is truly a cold start thx for any tips nice job on the video as well :)

excellent info! thanks

Nice Job. How does the fuel screw work?

Mark, ask your question on Thumpertalk.

Love your work, just like everyone else, rebuild my carby, this video is a life saver!

Gee556, if you have a crankcase full of fuel, be sure you're not leaving your petcock open when the bike is not being ridden.

Excellent video! I have a leaking carb that I'm rebuilding, this video was very useful, thanks! I have one question on which I'm unable to find any info online. After taking apart the throttle drum and putting compressed air on it, some sort of fabric washer flew out. I'm unable to find any info on where exactly this goes, and not sure if I should also replace it. Any idea what the function is of this fabric washer? Are there any other rings on that side that I might have blown out? Thanks!

@Trailryder42

2 жыл бұрын

Look at 17:28 in the video. Is that the washer you're talking about?

thank you for an awesome video i am currently building a honda xl 500 s 79 i am how ever having issues with the feul as the bike sputters and loser power at higher revs and from about Quarter throttle to open does the rubber airhose above the feul inlet hose make a difference weather it is blanked off or not or what else could be the issue the choke is open and i have hit a dead end?

@Trailryder42

9 жыл бұрын

cokes cokes Sounds like you're asking about the carb vent lines. Those need to be open ended, not blocked off. You may have vent lines coming from the carb that go upwards, like under the seat, and those that hang below the bike. They all need to be open and clear. The needle and main jet handle the fuel for 1/4 to full throttle. Go the thumpertalk.com and ask your questions in the XR forum for specific help.

Awesome Info to share. Thanks. Do you know if a good complete rebuild kit for the 98 XR400? TIA

@Trailryder42

5 жыл бұрын

I've read of folks on the forum using this kit, with good reviews. www.rockymountainatvmc.com/p/2896/49407/Shindy-Carburetor-Repair-Kit?v=3097

Appreciate the Knowledge. Best Xr400 carb video still almost a decade old 👍 i live in Salida Colorado, what size jets do you Run ? I'm at 7k elevation.. I took note of the needle on 2nd position in Colorado . I have a 02 xr 400 . Performance exhaust on it 155 main/ 55 pilot jet sputters at high speed, I just wondered what Size you like best in Colorado?

@Trailryder42

Жыл бұрын

I was running the Gordon modded stock exhaust, UNI air filter with snorkle removed. When I was still running the stock carb, I think I ran 150/50, needle 2nd clip at 9k where we would ride Rampart. Over 10k that jetting would sputter. Not knowing if your bike breathes with your mods any better than mine did at those elevations, it's and educated guessing game. But I'd say if it's sputtering riding high speed like it's rich, definitely come down on the main. Make 1 change at a time and evaluate. I had thought of trying 148/48 jetting but I never got around to it before I did the 440 big bore and Mikuni carb setup. Good luck with your experimenting.

@Ravetildawn420

Жыл бұрын

@Trailryder42 ,, I just bought the bike last fall .. no snorkel etc looks like all gordens mods.. Thank you for reply I think your exactly Right it's Running too Rich ! I tried a 160 main and sputter got worse .. . It sure had good low end puch thou I spun out and dumped it .. thanks again appreciate the info, and re assurance that I'm going in Right direction ✊️

So your saying, If the Minimum float level is lower than 14.5 (mine was like 9), If will most likely splutter and spit on rough terrain and high wheelies

you know your carbs👍🏁 currently i am in limbo deciding to rebuild my 2001 or replace with a pumper , dreading the pumper cost. what is your advice on compatablity with hot cams and big bore kits?

@Trailryder42

7 жыл бұрын

I could not dial in the stock carb with my 440 big bore no matter what I did. I went with the Mikuni pumper and never looked back. It has been great. My advice, if you go with a big bore, keep the stock cam and put that money toward a better carb instead.

@davidm5446

7 жыл бұрын

I had a Mikuni Pumper carb on my Suzuki DRZ400. The owner before me hadn't kept the air filter oiled and the slide was sandblasted. It rattled and caused all sorts of issues. I live in Cambodia so during the dry seasons here it's hard to keep dust out of everything. Anyway, couldn't do anything with that carb and went with a Mikuni CV carb as a replacement. Couldn't be happier with that decision. Still have all the power and now it's more reliable.

Thanks for the great video. I took my carb apart to check the position of the needle. Now I am not sure how to reassemble the arm that actuates the slide. I think I took the arm apart to get better access to the two screws that hold the plate to the slide. These are the two screws that you say not to bugger up at minute 15:12. (These two screws are numbered "25" in the parts diagram.) My actuator arm looks like the one in the video, but it seems I might be missing a collar based on the parts diagrams I have seen (like on rockymountainatvmc). The collar is shown just above one of the two screws labeled "25". However, I am wondering if the parts diagram is in error because the piece that bolts to the slide is definitely not shown correctly. The pin on that piece is shown extended to the opposite side of the piece that bolts to the slide compared to the one in the video. Can you confirm that whether the collar in the parts diagram is really part of the assembly. I can shoot a video of my actuator arm if that helps. Thanks!!!

@aajawo

6 жыл бұрын

Here is a video showing my slide actuator arm: kzread.info/dash/bejne/X6yjsLSGf9Dec6Q.html

@Trailryder42

6 жыл бұрын

I can confirm that the collar is not a part of my assembly either. And the bracket that screws to the bottom of the slide is turned 180* out in the diagram compared to what I know to be right. If you installed it like the diagram shows, it would cover the hole in the bottom of the slide that I talk about at 16:45.

@Trailryder42

6 жыл бұрын

The way you have it put together in the video is right.

@aajawo

6 жыл бұрын

Thanks! That is a relief!

Grate video. Are the float measurements the same for a xr250r 2003?

@Trailryder42

9 ай бұрын

No. The 250 standard minimum float level setting is 12.5mm, set as shown in the video.

I lost the freaking felt washer that is newer the throttle valve design to prevent dirt entering

Hey trailryder42. This is probably my fifth time referencing this video haha I have an XR and my brother and best friend do as well all 01-03 in years. So we take apart the carbs and clean em often. I just noticed that O ring on the manifold side of the carburetor around the outside of the carb what are you using that for? Thank you!

@Trailryder42

4 жыл бұрын

Hey Brandon. That's probably a spare intake manifold oring. Good a place as any to store it, with the carb. I wasn't currently using the stock carb when I made this video. Pulled it out of storage to do so, as I had been using the MIkuni TM36 for several years by then. Switched when I did the 440 kit.

@Scupper7

4 жыл бұрын

Trailryder42 ahhh makes sense hahaha thanks man!! I really appreciate the years of amazing advice I have to refer back to on thumper talk from you. Whenever I read a thread on the Xr400r I continue to scroll until I find your response. Whatever you say goes around here! Extremely useful info!

My 03 gets a third throttle bahg. Yet, it starts and runs good. It also runs really smooth sometimes, but then I go off a jump or let it idle and then it seems to loose a little power. Any thoughts?

@Trailryder42

3 жыл бұрын

Don't know what third throttle bahg is. If it's bogging out when landing a jump or even just g-outs and rough terrain, your floats max drop stop needs to be adjusted. From the factory it's set to like 25mm of drop. Doesn't need to be that much. It causes the float to bounce between stops. Set the standard minimum drop to book spec of 14.5mm and the max drop to 19.5., per the method I shown in the video. If you're having idling issues, the first thing I recommend is making sure the fuel screw passage is clean, the screws tip isn't broken off and that the oring is in good shape. Then tune it for best off idle response when quickly wicking the throttle open. You can't get it perfect with the stock carb, but good enough. I suggest you look up and join www.thumpertalk.com and become a part of the XR community there.

What is the substance that you are coating the screw driver tips with?

@Trailryder42

9 жыл бұрын

You can use any cleaning abrasive like Comet, Ajax, Bon Ami, etc..

I've managed to get my 2002 xr400 going and it starts easy and revs up ok after rebuilding the carb.. It has "bog" now and I am playing with the air screw. I changed the main and idle jets to 160 + 60 as per others recommendations and figured with more fuel coming in now it would require the air screw setting to be around factory settings (2+1/4 turns out) but found it gets nearest to having no bog at about 1 + 1/4 turns out. As I've already set the float, cleaned and rebuilt the carb with o rings and new jets, is it now worth looking at moving the main jet needle one slot higher? I believe bog is a lean condition and figure one slot higher could help more fuel come through earlier on the throttle on. Are there other things to check before doing this on these bikes to remove the bog?

@Trailryder42

Жыл бұрын

How are you testing for Bog? I suggest doing it on a warmed up engine, neutral, Idling, quickly open/close the throttle off idle. You didn't say what your elevation is. If you're running 160/60 jetting I assume you're near sea level and have airbox and exhaust mods. Moving the needle clip 1 slot higher is leaner. For richer, move the clip down the needle. The pilot mixture screw is not an "air" screw. It's a "fuel" screw. It meters fuel, not air. So, backing out the screw is more fuel, richer.

@carlosellatigo9378

Жыл бұрын

@@Trailryder42 Thanks again for responding here. I am testing a) as you say at idle and warmed up in nuetral, then also b) going for a ride and noticing the response as well. I'm at sea level in Tasmania start of winter about 10-14 degrees atm. I haven't as yet done the airbox or exhaust mods or "Gordon Mods" as people refer to them, as i had read that others had got away with moving to the bigger main and pilot jets for better start up and figured if I was rebuilding the carb I'd just put the bigger in straight away. Ok, so good to know about the fuel crew! Sounds like I am tightening and leaning it out which the bike likes more. Last night I put the clip lower, so should have even more fuel than before now, so theoretically it will like it even less and I should start to move toward leaning the mix and or looking at the other mods if I want to keep the big jets?

@Trailryder42

Жыл бұрын

@@carlosellatigo9378 The 160/60 jetting is for bikes near sea level and have had the stock screened air filter cage replaced with something like a much less restrictive, UNI filter and cage, pulling the under-seat snorkle and running a more open exhaust, like the Gordon mod or some aftermarket can. Those allow the engine to breathe better, take in more air, so that's the reason for the richer 160/60 jetting. I don't doubt yours is too rich with that jetting. Be sure you're not over-oiling your air filter.

@carlosellatigo9378

Жыл бұрын

@@Trailryder42 sounds like after I test ride her in a minute, if it's worse I might want to pickup the stock jets and see how they go. The air intake is stock although the filter type is a foam Hiflow. I guess I can hang onto these jets for if and when I choose to do the other mods. Thanks again 👍

hi sr, just bought an xr400r 98, i feel is not running as its supposed to, i feel it kind of sleepy, i was recommended to change the main jet to be 150 but i also have been told this is too much and can affect the spark plug because will make it use and burn gasoline that was not necessary, do you agree? i saw yours was a 160, what do think, should i use that 150 to make it run better? Thanks in advance.

@Trailryder42

4 жыл бұрын

Daniel, go to thumpertalk.com and post in the XR250/400 forum there. Need more info on your bike and location to be able to suggest jetting. This isn't the place for that.

@danielarbelaezg3451

4 жыл бұрын

@@Trailryder42 in summary i just wanted to know you experience with the 160 main jet you installed,?

@Trailryder42

4 жыл бұрын

@@danielarbelaezg3451 I don't think I've ever installed a 160 in my carb, as it's too rich for my 3600' elevation. I might have once for a few days, over 15 years ago, when I took my bike to ride the Sam Houston national forest. A 160 is what you'd usually run in XRs that have intake and exhaust mods, running near sea level. I couldn't tell you if a 150 would run better in yours without knowing what's currently in it, your elevation and intake/exhaust mods. From your description, you make it sound as tho it's running too rich and sluggish. So by deduction, that tells me you want to try a 150 because it's leaner than what is currently in it.

Good afternoon ! The high gicle is 160, what is the low gicle number ??? Thank you, and thank you in advance!

@Trailryder42

4 жыл бұрын

Sorry, I don't know what a gicle number is. But I'm guessing you're asking about jets. I don't know if you're asking about my jets or yours. Amadeo, if you haven't joined thumpertalk.com, you should. It has the best XR forum on the internet, where you can ask help for almost anything you need.

so by bringing the stock 25mm float drop to 19.5 I shouldnt have any stumbling on rocky terrain? I was riding today at uwharrie going up a very rocky steep hill with a very consistent throttle in 2nd gear when the bike stumbled a couple times up the hill, kind of like the engine just stopped for a second or two. is this the type of stumbling your talking about in the float height section?

@Trailryder42

3 жыл бұрын

If the mod doesn't eliminate it, it should definitely help. To be clear, this 19.5mm spec doesn't replace the standard 14.5mm spec in the shop manual. It's what you set the max drop allowed to.

@zackcarpenter5936

3 жыл бұрын

@@Trailryder42 right 14.5 min 19.5 max. Ill give this a try. one more question, what is the point of chamfering the pilot jet rubber tube?

@Trailryder42

3 жыл бұрын

@@zackcarpenter5936 Extending the reach of the pilot jets point of pickup lower into the bowl prevents the end of it coming out of the fuel level in rough terrain. I've never stated this but, as an aside, my thinking for the scarf is, during agitation of the fuel over rough terrain, to make it less likely that an air bubble could occlude the tube orifice.

@zackcarpenter5936

3 жыл бұрын

Ive noticed the overflow tube is wet with gas every time I ride the bike so Ive double checked my float height to the 14.5 min and 19.5 max but i noticed the two floats will read different heights depending on which side of the carb you measure. the part of the float that the pin goes through was just a touch crooked in line with the rest of the float so I straightened it. I also tweaked each float to be parallel to the other and have a perfct 90 degree bend on the back side where the metal bracket part of the float is. i then put the bowl on and filled the carb up with fuel to see how much fuel I get in the bowl before the float valve shuts it off. it filled the bowl up about 10mm from the top. also Ive got a brand new oem float valve needle installed. so I took the bike for a ride and even after double checking the float height the overflow tube was still wet. funny thing is I can jump on the bike up and down like a maniac to try and shake the carb to see if fuel will come out of the overflow but it doesnt. should I replace the floats? or is a little gas on the overflow tube normal?

@Trailryder42

3 жыл бұрын

@@zackcarpenter5936 The float pin fits the float tower well but the float piece itself that the pin goes thru is often sloppy. IIn the past I have squeezed that shut a little tighter on the pin, and then tweaked the floats side to side so they measure the same. Check the overflow tube in the float bowl to make sure it's not loose or the bowl has a hairline crack around the area. If it is, fuel could be leaking there and running down the outside of the vent line, making it look like you have a problem with float level.

What are the standard size jets for xr400 2003 model please?

@Trailryder42

10 жыл бұрын

The factory jetting for a 2003 XR400 is 142 main and 52 pilot. Honda jetted the main lean after '97, so a 142 may be too lean depending on where you live and any intake/exhaust mods done.

hi Emilio from argentina, in the minute 17,28 quote: this little....... my question what is that, and what material is it made of?? thanks. by the way excellent video man!!!!

@Trailryder42

3 жыл бұрын

Hey Emilio. That is a thin plastic washer/spacer. It goes between the drum lifting arm and the carb body. If you didn't have that there, the lifting arm would wear a groove in the metal body of the carb over time.

@emilionmartin7309

3 жыл бұрын

@@Trailryder42 yup, didnt have it, will have to invent one, thanks!!!

Hey Trailryder42, You seem to know what your doing so i got a question. My dad has a Stock Xr400 and i can wheelie that thing in 1st gear and get as high as i want, But in my xr400, It has a aftermarket exhaust, When i wheelie in 1st gear and get high, it bogs and spits and stutters. Why? Thanks.

@TSCtheTHC

6 жыл бұрын

You should be able to gas up a wheelie in 4th gear on a xr400. Anyways bogs spit sputter could be alot . from improper jets from pipe change , to a mouse nest in your airbox. bad gas ? you got to diagnose a little more for an answer.

Serious question. does your gas pee out when the float is stuck closed , or open? {closed as in pressed to the carb body closing the float valve?

@TSCtheTHC

6 жыл бұрын

my carb was peeing and when i took bottom bowl off. it wasn't dirty inside. the splash shield was on. but the pin that hold the floats shoulder was almost fall out . would that cause my float to stick open or closed to let gas go out over flow ? i ask because i have all my bike taken apart. and dont want to put it together before i know its fixed

@Trailryder42

6 жыл бұрын

It probably wasn't "stuck" open. With the float pin being about to fall out, it altered the shutoff point at which the float shuts off the needle valve and allowed the fuel level to rise to the level of the overflow tube. You can use a pair of pliers to gently squeeze the pin channel on the float, just a hair, to make the pin fit tighter. Do it the same amount on both sides. That usually has the added benefit of taking out slop in the float, as in rocking it from side to side. The loose pin fit can cause your float level on one side to measure one thing and something else on the other side. The pin can't come completely out tho, just because of the way the bowl is shaped around that area. I'd reset your float level(14.5mm), with a 19.5mm max drop. Make sure the inlet needle valves tip isn't showing a ring in it, as that is often a cause of fuel overflow. Be sure to always turn your petcock off too when the bike is put away, not being ridden or when being transported.

@TSCtheTHC

6 жыл бұрын

Trailryder42 thanks so much for a reply. I appreciate that. And I will try my best. I don't have a ruler that detailed though. I will try to eye ball ball your video of when you tip the carb

@TSCtheTHC

6 жыл бұрын

Trailryder42 I'm nuts and bolts literate. But your measurements. Are difficult to me. I bet you could get a bigger audience if you further explain the math. 👍👍

@Trailryder42

6 жыл бұрын

Firstly, I don't care about having a bigger audience. 14.5mm ( 9/16 inches ) is the stock minimum drop float height. That's the measurement you set while holding the carb as shown in the video with the float seating the needle valve but without compressing the little spring loaded nub. The factory doesn't set a max drop, but they should have. A 5mm ( 3/16" ) drop in the float from its position of seating the valve is enough to completely unseat the valve enough to keep the bowl full. So, 14.5mm (9/16") + 5mm (3/16" ) = 19.5mm ( 3/4") max drop. You set that with the max stop tab on the float arm as shown in the video. Leaving the max drop as stock ( which is as much as 25mm) causes the float to bounce in rough terrain, which causes engine stumble and can also cause stumble on steep inclines. You don't need a small metric ruler. If you have a regular inch ruler or tape measure, measure and mark from the end of a business card, 9/16" and 3/4". Use that to measure float height as shown in the video.

also is there really a difference in performance from the a15 to a16a needle? I have the a16a

@Trailryder42

3 жыл бұрын

I've never heard of an a15 needle for the XR400. I don't know if its nomenclature indicates it's richer or leaner profile than a 16 series needle. The A16 is the California needle, a leaner profile than the 49 state A16A.

@zackcarpenter5936

3 жыл бұрын

@@Trailryder42 oh ok I probably just misread some things about the needle

Anyone know how to install the throttle cables back on the carb and adjust them? I also think I stripped the float bowl screws (3). When i would place them in the hole, they would just fall right in as if the hole had gotten bigger somehow. I ended up buying bigger screws from oreillys dont like the result but i have to get the bike fixed.

@Trailryder42

3 ай бұрын

First off, when disconnecting the cables from the carb, DO NOT remove them from the cable bracket. Instead, remove the screw that holds the bracket to the carb and remove the bracket with the cables, their rigging adjustment intact. That prevents the headache of having to re-rig the cables later. I suggest you replace the screw that holds the bracket to the carb with an Allen head screw, 5mm x 12. To re-rig the cables, you're going to have to get the ends connected to the carb, then start taking out cable slack by pulling the cables forward in the bracket and adjusting the jam nuts to hold them in place. Move up to the throttle on the handlebar, rotate the throttle forward (closed) to feel for how much cushion you have (the amount you're able to continue to twist the throttle closed AFTER you feel the slide in the carb bottom out). If the slide doesn't hit hard bottom when you close the throttle, you need to adjust some slack into the PUSH cable, at the carb bracket, until you feel the slide hit hard bottom, plus having just a small amount of cushion in throttle travel after hitting bottom. Then adjust the PULL cable. Make sure the carb slide raises all the way at full throttle. If you don't get full opening of the carb/slide, still too much slack in the cable. Adjust the Pull cable so you get full carb/slide opening, with just a tiny bit of cushion at the end, (slide not opening any more but you can feel the little bit of cushion/over-travel pulling the cable taut. There's a cable adjustment at the throttle itself, but don't mess with that, as it was most likely set properly to begin with. It is a fine tuning adjustment only. If you messed with/backed out the idle speed adjuster or removed it, when you screw it back into the boss on the carb, it's initial setting is 17mm. Measured from the point where the end of the adjuster contacts the throttle drum to the surface of the boss where the adjuster comes out of it. As for the bowl screws. Those are 4mm x 16. I suggest Allen head screws for those too. If the holes have become oversize and stock screws no longer fit, you're looking at drill and tapping to up to the next size (5mm x 16).

@emozlut

3 ай бұрын

THANK U WILL TRY THIS DURING THE WEEKEND, IM SURPRISED NOT EVEN THE SERVICE MANUAL TELLS U HOW TO DO IT, OR IF IT DOES I DIDNT FIND IT. @@Trailryder42

Hi Mate, I have bought an 04 xr400r for the first time.I do not know much about the bikes 😕 A few days ago before l started the bike,l turned the idle screw and started it. But now I don't know where the idle screw should be 😞I just want to turn i back where it was. Can you please help?

@Trailryder42

Жыл бұрын

When you say "idle" screw, I take it you mean the black knob. It is not uncommon to need to turn that idle adjust screw Clockwise 1/2 turn to raise the idle speed a little for better starting, then turning it back after it's warmed up. It just depends on how low of an idle you prefer to run when the bike is warmed up. Running a super low idle is not ideal. Use the choke lever on full (lever all the way up) for starting a cold engine. The technique that works the best on the XR is full choke, bring the engine to Top Dead Center (TDC) with the kicker, leave the throttle closed and give it a good hard kick. Every starting kick should be made from the TDC piston position of the engine. If you don't, you're basically wasting your effort. There's a brass screw on the front side of the carb float bowl that points down. That is the fuel mixture screw for the idle circuit. You DO NOT use that for an idle speed adjust. I suggest you join the www.thumpertalk.com/forums/ Me and a whole lot of other XR folks with tons of knowledge on the XRs can help you over there better, with anything you need. I can even give you a link to a free downloadable shop manual to help you work on the bike. This is not a good place to go into a lot of detail.

@JustMe-yy7uc

Жыл бұрын

@@Trailryder42 Thank you very much for quick reply and for the information. I appreciate it very much. Kind regards..

Is this a stock carb? And what year bike is it off of?

@Trailryder42

3 жыл бұрын

Yes, stock carb and off of a US model 2000 XR400. It's the same carb from '96-'04.

is it possible for fuel screws to go bad(get worn out/grooving) or fuel screw orings to go bad? I just went down from 160/60 jets to 158/58 because when bringing down the idle of the bike and turning the fuel screw all the way in the bike would still run. problem is now that I have gone down to 58 pilot the bike will still run with the fuel screw all the way in. maybe I dont have idle low enough? I took the carb off the bike and noticed when I screwed the fuel screw all the way in it pokes out of the hole that its in infront of the slide. shouldnt it be seated before its able to poke out? even with the spring washer and oring removed it still does this. my assumption is either the fuel screw hole is larger than the fuel screw tip can plug or the fuel screw tip is worn down and too small to plug the hole completey

@zackcarpenter5936

3 жыл бұрын

I should mention I have a full fmf aftermarket exhaust system, uni filter,snorkle removed, proper float height and drop, and am at 700 altitude on a 60 degree day

@Trailryder42

3 жыл бұрын

@@zackcarpenter5936 Thanks for adding that info. Yes, it's not "impossible" for the oring to go bad/flatten/just get old and need replacing. If the fuel screw has even been overtightened when seating it, you most likely would see indications of that as an indented ring around the pointed tip. And I don't doubt it would effect the seating surface of the tiny hole in the carb. Seeing the point of it slightly sticking out from inside the carb throat when the screw is seated is not unusual in carbs., tho specifically in the XR carb, I don't remember. Personally, I couldn't care less if the engine doesn't die with the screw seated. I don't determine proper pilot jet size that way. I use the "whack the throttle" method, quickly opening the the throttle off idle and closing it, and tune the fuel screw for best, cleanest, no hesitation off idle response I can get between 1-3 turns out on the fuel screw. Wherever that point in screw adjustment is tells me whether I should richer or leaner. 2 turns out at that point is the ideal setting. If that point is only 1 turn out, I know to go to a leaner pilot jet, which have to make me open the fuel screw more, to find that same point and be closer to that ideal 2 turns out. Visa versa if that point was closer to 3 turns out to begin with. If you have questions about your fuel screw and oring condition, they're cheap enough to replace. Why did you replace "both" jets because the fuel screw wouldn't kill the engine?

@zackcarpenter5936

3 жыл бұрын

@@Trailryder42 good info trailryder thanks. I tried soaking the oring in penetrating oil to soften it up, hopefully it helps. yesterday morning I was riding in 50 degree weather and the bike stumbled a few times im assuming because it was running lean because of the low temp and smaller jets but once the weather got up to 65 degrees it was fine. but as for changing the main with the pilot I just assumed since I changed the pilot I needed to change the main. and yes I guess I just figured turning in the fuel screw all the way with low idle is the only way to find pilot screw sizing. but the bike did seem to really have some wonderful throttle response with the smaller jets especially in the warmer temps. with all that said im not going to go any lower than 158/58 since ive done all the gordon mods. perhaps the pro x jets im using are not true to size?

@Trailryder42

3 жыл бұрын

@@zackcarpenter5936 "perhaps the pro x jets im using are not true to size?" I wouldn't doubt it. I know knock off chinese jets are known for inconsistent sizing compared to Genuine Keihin jets. I have no idea who/where Pro X is made. Jetting recommendations always reference Keihin jets.

@zackcarpenter5936

3 жыл бұрын

@@Trailryder42 I looked on pro x website and they claim to run true to oem size but anyways I went ahaead and bought keihin 58/158/160 jets. im having a hard time finding a keihin 60 but anyhow it will be nice knowing i have oem jets. I also went aahead and bought a keihin fuel screw kit which looks like it may or may not come with oring. fingure crossed it does!

Honda XR400R done 4000km and was getting difficult to start Once started it would only run on half choke. So I bought a rebuild carb kit with all the needles and rubber rings. Hex Main Jet - #140 Slow Jet - #52 Jet Needle - D625 Fitment: Fit for Honda XR400R 1998-2004 Cleaned that carb like a new pin. Fitted the new parts. Paid attention to the original screw settings. Starts easily no choke. Open it up it dies. Put half choke on it just about let’s you open the throttle but doesn’t like it. Put full choke on and can open the throttle and drive about easily. What have I done wrong and what do I need to do?

@Trailryder42

10 ай бұрын

What is your elevation? When you cleaned the carb, did that include removing the fuel mix screw, it's spring washer and oring to make sure everything was there and the oring was in good shape? Blast that passage with cleaner? It almost sounds like you're using the choke lever positions opposite of intended. Thinking OFF ( lever down) is Full choke and Full choke (lever up) is Choke off. Any exhaust or airbox/filter mods from stock make a difference in jetting, so need to know those to.

@markhodgkinson151

10 ай бұрын

I did everything you said. Choke Off is down and choke on is up. I’m at 1,300 feet up from sea level.

@Trailryder42

10 ай бұрын

@@markhodgkinson151 I can find no info on Jet Needle - D625. Don't know its specs or who makes it. What air filter are you running? Becoming difficult to start is also a sign that the valve clearances are tightening up. Clearances get tighter over time and with wear. Check/set clearances to rule out those being the problem. Do you know the specs and procedure for doing that? If you're running something like a UNI air filter and have any mods to the stock exhaust, a 52 pilot will be too lean for 1300' elevation. I'd be running at least a 58. That 140 main would also be way too lean for 1300'. I'd be running a 158 to begin with. The required use of the choke is saying it's showing signs of being too lean. Look for air leaks too. The intake manifold oring periodically needs replacing.

@markhodgkinson151

10 ай бұрын

@@Trailryder42 Your comments are so helpful. I double checked my points and your questions. The altitude is from 300m to 600m on a mountain. It lives at 300m but I ride it up to 600m on every outing. Do you think I should go even bigger on the jets? The carb kit was bought on eBay The air filter is a HiFlo Filter bought on eBay I’ve watch videos on valve clearances and I think they should be 0.1mm in and out but will check the manual to be sure. The procedure looks simple but I need to double check the clearance gaps. I haven’t modified the exhaust and think it’s totally stock. I think the carburettor has a spring flap on the choke flap with two little holes in it but I can’t remember because it’s on the bike now. The intake rubber looked ok on inspection but I will double check again.

@Trailryder42

10 ай бұрын

@@markhodgkinson151 So your elevation range is from about 900 to almost 2000 feet. I'm guessing, from what I can find, the Hiflo air filter is a foam filter? Do you lightly oil it? You should but don't want to oil it so heavily that it leaves a puddle in the bottom of the airbox. Is the cage it slips over the stock stainless steel cage of a Hiflo plastic cage? I don't think mm feeler gauges are accurate enough if they're only in .1mm increments. Use SAE gauge. Intake is .004 inch and exhaust is.005 inch. Be sure you set the engine at TDC on the compression stroke. If you have that right, you should be able to put you finger thru the access ports and feel wiggle in all 4 subrocker arms. Follow the shop manual to be sure your manual decomp system/lever on the handlebar is in spec before and after any valve clearance adjustment you make. If the carb choke plate has a spring loaded flap on it, that's the stock piece. If no spring loaded flap and it just has 2 holes, that's an XRs Only style plate. Did you check/set the carbs float level? If that's off, it will have a big effect on how the engine runs. If your lean problem is float related, it means it's set too low. This video shows how to set it.

How do you get rid of the bog when I twist the throttle fast from idle to full throttle

@Trailryder42

Жыл бұрын

It can be difficult to get rid of it completely. It takes proper/careful jetting/tuning of the pilot circuit (fuel screw and jet) and proper clip position of the needle for the transition from pilot circuit to midrange. But just given the nature of the 4 stroke engine, in which you have a compression and firing of that compressed fuel charge only once every 4th stroke, whacking the throttle open and expecting instant response when the engine is in some other stroke besides that, is unrealistic. Besides, whacking the throttle open from closed to near full is not a real world, actual riding, throttle input. Tune it for the best off idle response you can get for actual riding and go with it.

@kylechupick2232

Жыл бұрын

@@Trailryder42 I re jetted for the pipe and air box. Can the fuel screw cam be adjusted with the carb still on the bike

@Trailryder42

Жыл бұрын

@@kylechupick2232 The fuel screw is that brass screw at the front of the carb float bowl pointing down. Yes, it can be adjusted with the carb on the bike. Turning it IN, clockwise is leaner. OUT, counter clockwise is richer. You should never go more than 3 turns out from fully seated. For your elevation, intake and exhaust mods, you want to try to size your pilot jet so that your fuel screw setting, when you have it adjusted for best off idle throttle response and power, is around 2 turns out, ideally.

Hey, sorry to bother you again but a new problem has arrived (so sick of this crap). After i adjusted the floats and cleaned out the carb, it ran perfectly, the next morning i took a ride to work, after 5 minutes of gentle cruising, i stopped to cross a little bridge and when i slowed down and ran in 2nd and 1st gear, it spitted and sputtered and felt like the choke was on, It went away after riding again. after work finished i got on to head home, after 5 minutes again and when riding in 2nd and 1st gear and was running like total crap. I got home and cleaned out the carb and yet after i rode for 3 minutes, it did it over and over again until finally and stopped. It ran fine for 2 days until i chucked a fresh batch of fuel in and went to work, 5 metres down the road, it started doing it again. It felt like the choke was on. I came home later and cleaned out the carb and put the bike away, i didnt ride it. The next morning i rode it and it ran fine until later in the day, i popped a wheelie and then it started acting up. I went for a small trail ride and every now then, it started acting up and then stopped, and then started again and did this every now and then. Works for 5 minutes and then runs like crap for 5 minutes. This is really annoying and i really just want my bike to run fine. sorry for the long comment Thanks

@TSCtheTHC

6 жыл бұрын

adjust your valves?

@walterconn5637

4 жыл бұрын

The vent on the gas cap could be clogged.

Hello sir , i have problem with my 97 xr400. It bogs on 30 % of throttle. Can you tell me how can be fixed this problem ? Thank you

@Trailryder42

2 жыл бұрын

Go to Thumpertalk.com in the XR400 forum, make a new post and ask your question there. There's not enough info about the bike and it's history posted in your question to make a detailed analysis and recommendation. But I would definitely start with cleaning your carb and it's jets and make sure they haven't fallen out.

My 2000 XR400 bogs when i roll the trottle. if i put just a slight amount of throttle in first it doesnt bog. could this be a float adjustment issue? Iam also in CO. I tried adjusting the air/fuel needle and it doesnt make a difference.

@Trailryder42

3 жыл бұрын

Pull the fuel screw, it's spring, washer and oring. Make sure all those parts are accounted for and blow out that passage with carb cleaner. Make sure the oring is in good shape

@100bjj5

3 жыл бұрын

Trailryder42 will do....thanks.

@100bjj5

3 жыл бұрын

Trailryder42 o-ring looks new. cleaned it out with carb cleaner and reinstalled, didn't make a difference. I'm thinking it could be because the pilot jet is a little too lean. What are your thoughts?

@Trailryder42

3 жыл бұрын

@@100bjj5 Post what you're current jetting, airbox/filter and exhaust configuration is. Is the bogging off idle only a recent happening? Ran ok before? Make sure the backfire flap of the choke plate is still present, if it ever was.

@100bjj5

3 жыл бұрын

No clue what the jetting is. I haven't owned it for very long and didn't notice it until recently. It has stock exhaust and stock oiled air filter. I took it up to 9000 ft to see if it made a difference and it did not. I was thinking about taking off the carb and see what pilot and main jets are installed and what the needle setting is. What are your thoughts?

does anyone out there know how to put a xr400 back together?? my son took motor out and rear end off because it wouldn't start?????

@Trailryder42

7 жыл бұрын

Yes. Ask in this forum. www.thumpertalk.com/forums/forum/18-xr250400/

my bike is a bear to start.. like if it starts in 20 kicks im doing ok.. once it runs it runs mint.. problem is I put a 10:1 top end and has a hotcam so if I don't use the manual decompression correctly.. I break parts.. I broke the kicker spindle.. then 2 teeth off the gear... bout to just buy a pumper carb..

@Trailryder42

6 жыл бұрын

Stephen, it sounds to me like you're not bringing the engine to TDC for EVERY kick. You MUST do this, especially on a big bore or high compression XR. Should be done with any XR. It's the best place, and most of the time, the only place in the stroke that the bike will start consistently from. It also takes the least effort on the kicker, saving broken parts. With the kicker, bring the engine to just before TDC, (that spot where it's hard to push thru). The piston is coming up on its compression stroke there. Leave the weight of your leg on the kicker. Feel the cylinder pressure bleed off and the engine moves past that hard spot and you feel the piston fall into a detent. That is TDC, where you should start every kick from. Right after that detent is a mildly hard spot as the piston breaks over TDC, that's easy to kick thru because that's the piston starting it's way back down. Because you're starting your kick from there, the engine has momentum on it's own to make it thru the next TDC compression stroke on its own, partly because of the auto decomp on the cam. Another thing that happens kicking it like this is, you can generate more rpm with your kick, which the CDI needs in order to trigger a spark to the coil.

Just playing around with this atm. Does anybody know the air screw washer sequence if you were loading it up before your screw it in goes: the spring then washer then o ring, or is it reverse with the washer sitting "on top of the spring" and the o ring nearest the screw driver end? Cheers.

@Trailryder42

Жыл бұрын

You slide the spring onto the screw first, then the washer , then the oring. So when you insert the whole assembly as one, the oring is leading the way and will settle into its seat at the bottom of the hole.

@carlosellatigo9378

Жыл бұрын

@@Trailryder42 thanks very much for that. I figured it was but mine was missing or desintegrated!

@Trailryder42

Жыл бұрын

@@carlosellatigo9378 If the oring doesn't come out with the rest of the screw assembly, look up in the bore and see if it's still in there. If it is, be careful blowing it out with compressed air so as not to lose it. I will often have to fish it out with the wire from bread bag tie or piece of safety wire, with a tiny hook bent in the end.

@carlosellatigo9378

Жыл бұрын

@@Trailryder42 Thanks for that tip. I was actually wondering if it's possible for fuel that's gone bad to wear away the o ring so much it desintegrates, as when I removed the screw there was a slimy black oil like film on the threads, and no o ring. The bike had a very laquered bowl and other components I've had to soak and clean numerous times.

@carlosellatigo9378

Жыл бұрын

@@Trailryder42 when you say bore, where do you mean exactly?

Found it haha

Anyone else problems installing that nasty little plastic splash plate on the main jet housing? I had to leave it out for the time being...

@Trailryder42

3 жыл бұрын

It shouldn't be difficult to put on, as it only goes on one way, in order for the overflow tube in the bowl to mate with it properly. As seen at 6:52 in the video, that half moon cutout to accept the overflow tube points to the rear of the carb, the side farthest away from me. The baffle fingers index with raised ridges on the jet tower. You can gently heat the fingers and bend them in a little so the finger grip the tower better so it can't come off on it's own. You can see in the video, mine grips pretty tight.

take a mikuni cabulator