Yamaha rd350 Road Racer Liquid Cooled!!

Hurco550

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Re: Yamaha rd350 road racer

Have any of you guys used the banshee pistons in an r5 top end vs an rd350 top end? I can't imagine there would be an issue doing so, but I figured I'd ask
 

davedogg

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Re: Yamaha rd350 road racer

Pretty sure you cannot use banshee pistons on a R5. The R5 is piston port and doesn't have the windows that the reed valve RD and banshees have.
 

Hurco550

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Re: Yamaha rd350 road racer

davedogg said:
Pretty sure you cannot use banshee pistons on a R5. The R5 is piston port and doesn't have the windows that the reed valve RD and banshees have.
Well dang. Thanks for the info though man
 

Hurco550

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Re: Yamaha rd350 road racer

Maybe I should build an Rd top end after all then, but teazer has already been putting a bunch of time into r5 port maps for me though
 

clem

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Re: Yamaha rd350 road racer

The Banshee pistons do work in the RD350 but they need to be modified. Good quality R5 pistons may be hard to find. I think that Wossner may be the best bet.

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Hurco550

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Re: Yamaha rd350 road racer

clem said:
The Banshee pistons do work in the RD350 but they need to be modified. Good quality R5 pistons may be hard to find. I think that Wossner may be the best bet.

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I did read about filing of the tab on the intake side for the rd's, I just assumed it would be the same for the r5,but it seems like that is not the case
 

Hurco550

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Re: Yamaha rd350 road racer



clem said:
Good quality R5 pistons may be hard to find. I think that Wossner may be the best bet.

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Wossner pistons are about $130 a pop. Seems steep to me, but maybe that's the going rate for a quality piston these days
 

2_DONE_THE_TON

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Re: Yamaha rd350 road racer

This was one of the reaons i didnt buy a R5 cuz the pistons are really hard to get in Europe...I used on both of my RD stages (Stock 250 setup and modified 350) the pistons (Pro-X pistons) of the watercooled LC 350 (250)...they worked fine on the 250 and the 350 setup.
I still got my RD 250 jugs and pistons in my shelf, so if youre planning to go for that, let me know (shipping might be expensive from austria).

I also thought about going for Wossners but I went for Pro-X in the end, a friend explained to me that going for A to B in the city is not right thing for them (forged steel needs more time to warm up and i think its bored the lower play).
 

Shoeman

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Re: Yamaha rd350 road racer

hurco550 said:
Maybe I should build an Rd top end after all then, but teazer has already been putting a bunch of time into r5 port maps for me though
Is he porting a set for you or just drawing port diagrams? Here's basic RD setup for street use: Raise exh port 1mm, widen it 2mm. Widen the intake 2mm and remove the lip at the cylinder on the port floor. Make sure both cylinders match when you're done. Leave the transfers alone unless you have a right angle hand piece. Match the case top to the cylinder base if you like. Cut the center tab off banshee Pistons as you already know bolt it back together and let it rip.
 

teazer

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Re: Yamaha rd350 road racer

I'm just working up some porting options and looking at his pipes. RD350 has basically the same ports as an R5 apart from the extra boost (intake/transfer) port.

That's a nice mild clean up Shoeman and would work well with his pipes. They may need to have the headers shortened though. I'll run a few more numbers.

I agree that an RD350 top end would be preferable and pistons are readily available versus not so much on an R5. Could use TZ350 pistons in an R5 on stock bores I guess but not a great choice for the street.
 

Shoeman

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Re: Yamaha rd350 road racer

Teaser, are you calculating his pipes reflected (or tuned) length and seeing how that matches various exhaust port Timings? I used to spend hours doing that sort of thing, first on paper using Jennings info, then later with TSR programs back in the Win95 days when those became available. I don't know you but it sounds like you take a solid scientific approach, hats off to you. I quit the racing and tuning game quite awhile ago now but I was the same way and my motors won a lot of races and satisfied street guys too. I'd add that in most cases like this, optimizing the pipe is not a necessity. It will gain that last extra edge for sure but on a street bike it's a luxury. Unless of course the pipe is a torquer by design and the ports are set for higher revs than the pipes are. The. You get a nasty powerband for sure
The reed valves and the 360deg intake timing they allow make a huge difference in how you can ride the RD vs the R5. Much easier. It's like power valve exhausts, the flexibility they gave was a real revelation back in the day. Every generation of Yam got better.
 

Shoeman

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Re: Yamaha rd350 road racer

Absolutely. With that development you could now maintain all that horsepower you had created. Unless you blew it up
 

teazer

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Re: Yamaha rd350 road racer

Shoeman said:
Teazer, are you calculating his pipes reflected (or tuned) length and seeing how that matches various exhaust port Timings? I used to spend hours doing that sort of thing, first on paper using Jennings info, then later with TSR programs back in the Win95 days when those became available. I don't know you but it sounds like you take a solid scientific approach, hats off to you. I quit the racing and tuning game quite awhile ago now but I was the same way and my motors won a lot of races and satisfied street guys too. I'd add that in most cases like this, optimizing the pipe is not a necessity. It will gain that last extra edge for sure but on a street bike it's a luxury. Unless of course the pipe is a torquer by design and the ports are set for higher revs than the pipes are. The. You get a nasty powerband for sure
The reed valves and the 360deg intake timing they allow make a huge difference in how you can ride the RD vs the R5. Much easier. It's like power valve exhausts, the flexibility they gave was a real revelation back in the day. Every generation of Yam got better.
I have his pipe dimensions and a couple of pieces of software: Bimotion to work out target port sizes and MOTA to do the simulations. last night MOTA started dropping out so I shut off the PC and this morning the power supply fan failed and started to smell and then ...nothing. SO I just swapped in a new power supply and will try again this evening.

I then start to move the variables over a range to see the impact on the shape and size of the powerplot. In this case the starting point is the pipes that he has with header changes and then a few simple port mods. I have a set of TZ750 barrels, off my last TZ350, if I need more inspiration.

Water cooling really helped them to stay together and on an RD350 there are all sorts of reed options. An RZ350 has the same size reed cage as a TZ750. The best is probably a YZ85 cage with a few subtle mods but for a mild motor stock cages and different reeds are enough.
 

Hurco550

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Re: Yamaha rd350 road racer

Man, I love hearing you guys that know your stuff talk!

Just got back in town. Went back up to the salvage yard where I got the bike in the first place, and picked up the important part.... he found the title so now I don't have to go the Vermont route! It's already open notorized to boot.


Also traded him one of the akront hoops for a xs650 high shoulder that should lace right up with out much issue. The one i traded was for a non symmetric hub (probably ducati) and wouldn't have laced right. I have to un lace this hub and give it back to him.
 

irk miller

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Re: Yamaha rd350 road racer

I dunno why, but it's very satisfying to unlace a wheel with a pair of bolt cutters.
 

Hurco550

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Re: Yamaha rd350 road racer

deviant said:
I dunno why, but it's very satisfying to unlace a wheel with a pair of bolt cutters.
He wants the crusty old spokes back =/
 

Hurco550

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Re: Yamaha rd350 road racer

clem said:
Of course one day he'll get around to re plating those old things.

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Ha, this guy, well two brothers have been at the M.C. salvage business for years. NOTHING gets pitched, which is probably part of why they have over 700 bikes + gobs of parts. I remember my first trip over there. I needed some parts, one of which was a fuse box for a cb550.the old one was trashed, cracked plastic, broken tabs and what not. They had me bolt it on the parts bike in place of the one I got. Seriously, nothing gets thrown away there lol
 
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