Love this Engine layout. The bottom end is more or less the same as the 1972 YDS 7 i had. Yamaha knew what they was doing when they designed this Engine.

@keithdawson4804

2 жыл бұрын

Basically same bottom end as R5, from 1970 until last (Brasilian) RZ350 of 1995. And plus the Banshee ATV motor.

Thank you for taking the time to document this process so well. With this resource, I think I can finally take on a full rebuild!

Best 2-stroke Bike ever, i want turn back time 😍

Spot on, just disassembling a 250 LC motor and always nice to have a video like this to help put it back together!

@taffyboy07

3 жыл бұрын

Your stripping a 250, he's rebuilding a 250 also, engine number 4L1

That’s one of the most interesting videos I’ve ever seen! I owned (and loved) my RD250 LC when I was 17.

@jh-tech5546

2 жыл бұрын

Thank you!

8:40 heating up the casing before inserting the bearing .....nice touch.

Sou apaixonado por motos 2 tempos da Yamaha,tenho recentemente uma RD 350 1991,uma DT 200 1993 ,e uma RD 135 1997, gosto demais delas😍😍😍😍

Merci pour le partage. je suis au début de la vidéo pour le remontage de ma 350 modèle 31k. Très utile pour me permettre de pas faire trop de bêtises. A priori c'est pas le premier que vous remonté. Félicitation.

Super nice vidéo. That have made me remember when i was young and crazy.

Brilliant video. Thanks

wow what a beautiful video...superb neatly done...

Good work Man!

Stunning. Thanks.

Excellent video, and thank you for posting that. I still have my 1985 (American market) RZ350, purchased new that year. I've rebuilt it completely once, with a couple of extra top end builds as well. I expect I will be doing it again some day!

@jh-tech5546

Жыл бұрын

Thank you for your comment. Nice that you still got your bike from back then. My brother got an RD350LC like mine nearly 30 years ago. And we still regret having sold it.

@Rollin_L

Жыл бұрын

@@jh-tech5546 I can imagine. Many times I have been asked to sell my RZ350. Fortunately, even during extended periods where I am not riding at all, I've resisted some pretty good offers. I have far too much history, and many memories with this machine.

Good work and im ready to share your neat work and full support for your channel from my side

You are a maestro!!!

Thenk you If you only knew how much joy folk with your skill gave a generation

@jh-tech5546

2 жыл бұрын

Thank you

WOWO... thank you... awesome video ..

Superb 🏆👍

Excellent work done

@jh-tech5546

3 жыл бұрын

Thanks!

wow love it....make the same on a aircooled 350

One☝🥇 of the🌎🙏 great engine work

thanks a lot ! helped out

Nice

Que cslidad de motor ,deberian de hacer para el mercado

favoloso

Top!!

Bello ese motor ( Venezuela )

top adoro minha s rds

eccellente

Thank you for posting the video

Have built many of these and 400 motors "not that much in it" but I've never built one without lubricating every part!

@jh-tech5546

2 жыл бұрын

Thanks for your comment. Don't worry. Parts where lubricated where needed. Not all on camera maybe.

Great video, brought back many memories... A mis-spent youth meant that If you gave be a complete box of RD400/250F parts I would be able to get over 95% in the proper place without a manual including the settings even now. Wasn't that a 250 bottom end crank case 4L1 instead of a 4L0? So long that I can't remember which way round it was. For the Air-cooled it was 2R8/1A2 for 250 and 2R9/1A3 for 400....??

@jh-tech5546

3 жыл бұрын

Correct 4L0 is 350 and 4L1 is 250. Unfortunately i don't have matching numbers. But he complete bottom end of the engine is the same appart from the oil pump i think.

Thank you, you did great, displaying every part of assembling of engine. It helps me alot to get it done by myself. I had query that can we fit rd50lc barrel and head over rd350 chassi air cooled, using external motor to move coolant through the barrel to radiator. As we didn't have lc engine case ,only we can manage to get lc head and cylinder barrel Regards, Ramva

@pauloconnor7951

3 жыл бұрын

Yes you can.

Seems like a fun engine to work on! Might get one soon for a project bike

@adolfshitler

2 жыл бұрын

Hope you've got deep pockets, the price of these things lately has gone through the roof

@Nelis1992

2 жыл бұрын

@@adolfshitler already have one 😉 also picked up a Aprilia rs250 with no engine. Guess what im going to do with those 😎

@adolfshitler

2 жыл бұрын

@@Nelis1992 Please tell! Genuinely interested to know all. I've had a LC 350 and a very highly tuned 400. Loved the things

@Nelis1992

2 жыл бұрын

@@adolfshitler I havent had a big 2stroke before. Just some dirtbikes. But the plan for this bike is a RS250 base with a RD350 engine. Ive even seen swapkits for this job. So thats no problem. Challenge will be the exhausts. Reason for the swap is mainly because rs250 engines are hard to find and stories of unreliability. But also the tuning potential of the rd350 engine :)

@adolfshitler

2 жыл бұрын

@@Nelis1992 Go for it, sounds like great fun. I've had a couple of LC 350s and an Rd 400, that got the nads tuned of it. Yamaha TZ750 single ring pistons taking it out to 440cc with a Steve Colster mild port job. Yamaha TZ 350H expansion pipes, welded to fit on the headers, D&G radial heads. Can't remember what carbs/reeds i ran on it, and a mono shock conversion kit. Looked a mess but went like stink, and completely unreliable, a crank every 1500 miles. And all built on a budget in my dad's shed. I'm now thinking about a GT 500.

Some captions would help us newbs follow along - great video !

@jh-tech5546

Жыл бұрын

Thanks for your comment. That is a good idea. I might try it once.

Wat did you use to seal the case

Buenisimo usted me podría decir para que sirve el.oring que va en la parte de atrás de la canasta de embrague al lado del en engranaje gracias saludos de Argentina.

@jh-tech5546

3 жыл бұрын

I am not 100% sure but I think it is used to dampen some noises in the clutch

Risked it putting pistons on no rag to stop it going in crank case but I expect he's done this a couple of times

@jh-tech5546

Жыл бұрын

Thanks for your comment. YOLO :) If the engine would be in the motorcycle frame I would indeed add rag but here I suppose I could turn the engine arround and hope the clip would fall out. But you're right.

very cool video, thumbs up! One question: I've read that blocking the primary drive with a rag or penny inadvertently warps the crank to the point of ruining it. I don't know if it is true, but it seemed credible to me. Particularly since more often than not when Ive taken apart an LC bottom end the crank was warped and separated on the flywheel side. The German source where I read that said that blocking it like you do is even written in the official service manuals, but he claims he's measured it and it always ruins the crank. Do you think this might be BS?

@jh-tech5546

3 жыл бұрын

Thank you. I only block the primary drive to tighten the nut on the same side of the crank. I agree that it's not recommended using this method to tighten the flywheel nut, that would indeed cause some torsion on the crank and could warp is. For the flywheel side I used a tool that can block the flywheel.

4L1 engine # - started its life as a 250.

@jh-tech5546

3 жыл бұрын

Correct, unfortunately i don't have matching numbers. But it will be the same fun to ride :) One important detail i need to change is the oil pump. That's the only change between 250 and 350 engine bottom.

Put the piston pin circlip in wrong but pretty close

Pretty similar to the banshee engine.

Is the neutral switch plate fitted at 7:38 supposed to have 2 out of the 3 mounting holes split?

@jh-tech5546

Жыл бұрын

Hi. No, it is not. Those are cracks. Nearly 40 year old plastics.

Sorry, in another video I saw the clutch assembly and it is different from yours; in your video you start putting the garnished disc (in cork) and after that the O-ring. While in the other video we start with putting the O-ring first. What is the right sequence?

@jh-tech5546

3 жыл бұрын

I don't think it matters because the o-ring fits inside the cork disc. The cork disk inner diameter is bigger than the clutch inner basket and the o-ring fits in between i you understand what i mean.

what reassembly lube do you re commend? great video!

@jh-tech5546

4 жыл бұрын

Thanks! I don't think it really matters, it's just for assembly and for the engine's first couple of revs. I would recommend using your regular two stroke oil for the crank, piston and cylinders and the transmission oil for the gearbox and clutch parts. You could also use some grease in the sealings on the contact surface (i didn't do it). I did use a teflon based bicycle chain lube on the seals, two stroke oil on the crank, and pistons and regular 10W40 4-stroke oil on the gearbox side.

@DADSON-sx8yv

3 жыл бұрын

Great job

👍✌🏍🏍🏍🇫🇷

ok

4L1 say its a 250cc engine no o-rings for the clutch ..

@jh-tech5546

2 жыл бұрын

THanks for your reply. The engine casing is stamped 4L1 so it was from a 250cc originally indeed. In the meantime I had to change the clutch plates due to slipping and i removed the o-rings. I't is working fine.

How long di it actually take to assemble?

@jh-tech5546

2 ай бұрын

Not sure, I guess one or two hours.

@elfspicer

2 ай бұрын

@@jh-tech5546 Very cool video mate, thank you. A very long time ago I did two seasons of racing on a 350LC. It was a magical experience. Those were good days.

That head gasket looked weird.

@jh-tech5546

Жыл бұрын

Maybe because I put a layer of vaseline on all my gaskets? It is an old habit that should help to prevent the gasket from sticking when disassembling.

@TS50ER

Жыл бұрын

@@jh-tech5546 👍

Where can I get rd 350

Is that engine assembled dry? Except a light coat of oil on the rings.

@jh-tech5546

3 жыл бұрын

I did lube all moving parts but unfortunately most off camera. The crankshaft bearings all oiled with two stroke oil as well as the cylinders. However before starting i will squirt some more two stroke oil in the inlets and make sure the oil pump is functioning well.

@alwaysask1

3 жыл бұрын

@@jh-tech5546 I assumed that you are proponent dry assembly. I have been reading benefits of dry assembly.

@Biconnecc

3 жыл бұрын

@@alwaysask1 there are no benefits of dry assembly. only broken parts

@JETZcorp

3 жыл бұрын

@@Biconnecc That's not true. Dry assembly leads to a faster and more thorough ring bed-in. Lots of assembly oil can create a sort of glaze on the bore that stops the process and makes the break-in take forever. A lot of cars are actually assembled dry for this reason. They used to have cars smoking on their first test drive because the ring seal was so bad, and dry assembly fixed that.

psdb campaign

Иж и то сложней собрать

Yamaha 4L1 is not a 350 LC....its a 250 LC

@jh-tech5546

2 ай бұрын

You are correct. The crankcases left the factory in a 250.

if ya wanna get about another 1000 rpm, use german main bearings. woo hoo go fast!

@jh-tech5546

2 жыл бұрын

Thanks for the tip!

Really should so away with the background noise.