Yamaha rd350 Road Racer Liquid Cooled!!

Hurco550

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Re: Yamaha rd350 road racer

Great to know about the crank and side load on the bearings! And the tank.... I had it on the wall so I sat it in there ha. When the right deal comes along I'll pick up a property tail section and tank. I'll see what mid Ohio has in store
 

VonYinzer

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Re: Yamaha rd350 road racer

hurco550 said:
Great to know about the crank and side load on the bearings! And the tank.... I had it on the wall so I sat it in there ha. When the right deal comes along I'll pick up a property tail section and tank. I'll see what mid Ohio has in store
I have a couple glass race seats on the shelf. Different designs but both vintage "cafe racer" style. I'll get you some pics when I get back into town Monday if you're interested.
 

Shoeman

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Re: Yamaha rd350 road racer

teazer said:
TZ outer main bearings are much better than the street bearings but cannot be used on a crank with helical primary gears. They must be straight cut to use them because unlike balls, they can't take the side loads. So TZ cranks for bikes with straight cut primaries and dry clutch and regular bearings for street bikes with helical gears and wet clutch.
All true. I used to use Tz bearings everywhere but the primary side. Makes for a strong crank but overkill for street use.
 

Hurco550

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Re: Yamaha rd350 road racer

VonYinzer said:
I have a couple glass race seats on the shelf. Different designs but both vintage "cafe racer" style. I'll get you some pics when I get back into town Monday if you're interested.
Sure thing man, that would be great!
 

clem

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Re: Yamaha rd350 road racer

Some people hate the Vito cranks and some dig them. I read about a guy that put a couple thousand miles on one and said it was still fine. Another put a couple hundred and said the vibration was picking up. I had Mr. Garland rebuild my crank and he did an excellent job. Yeah I've missed a few shifts that went past 10k and I try to ring its neck now and again and it still feels solid.

Sent from my SAMSUNG-SM-G920A using DO THE TON mobile app
 

teazer

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Re: Yamaha rd350 road racer

We shift at 10,500 on a 350 with heavy pistons and a little more on a 250 and cranks last as long as they have the right rods and we don't hydro lock motors and try to start them on rollers - that bends rods which then rub on crank wheels until they get hot enough to snap. Not a pretty sight.

Lynn Garland is an all round good guy and very experienced builder of Yamaha twins.
 

Shoeman

Member
Re: Yamaha rd350 road racer

teazer said:
Lynn Garland is an all round good guy and very experienced builder of Yamaha twins.
Yes indeed. We used to share garage space at NHIS during USCRA races. A very distinguished gentleman with a fine collection of Yam race bikes. An added bonus was the fact that he is friends with Kevin Cameron, who would stop by and visit our pit on occasion. Man, those were the days.
 

sav0r

Member
Re: Yamaha rd350 road racer

I have a Vito's in my RD now. Seems fine but I don't have a lot of miles on it quite yet. I'll rebuild my OEM crank in the offseason with the hope of eventually having a complete seciond engine eventually. For the price of the Vito's though it really can't be beat in my opionion. Especially as a drop in unit, and there is something awfully nice about it just showing up and dropping it in. That said, if I were going racing where I'd be expecting to run flat out in the upper 20% of the RPM range all of the time I think I'd stick with a well serviced OEM unit.
 

alzcbz

Member
Re: Yamaha rd350 road racer

Vito's does a lot of Blaster and Banshee mods. RD350 mods are common for the Banshees. Very reputable, never heard bad about their products, not to mention they are somewhat local to me.
 

Hurco550

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Re: Yamaha rd350 road racer

Thanks for the replies on the crank. There is currently a nos crank that I'm trying to get my paws on, if not I'll probably try to grab one of those new vitos. I'm also on the prowl for an electronic ignition. Trying to decide if I should go with the full setup with stator, coils and all ($$) or just one to delete the points. For now, until I get some scratch to really build the motor, I'm gonna try to get the chassis straight. Nothing special for now. Trying to track some aluminum hoops to lace on, tapered neck bearings fork seals ect... should also probably track down some rear socks as well. Also gonna work to make the proper mounts for the fairing.

I'm not planning to build this motor to the ragged edge on tuning, but I have read that there is plenty of unlocked power in these things with some tuning,so we shall see where she ends up. Planning to grab an fzr rotor from vonyinzer to fit to the front and help with the whoa as well.
 

teazer

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Re: Yamaha rd350 road racer

Match that new rotor with almost any modern 2 piston sliding caliper and the thing will stand on its nose.

DYNA S is cheaper and allows you to keep the stock lights and charging system.

Motoplat/FEMSA/Hitachi/PVL/ etc is best for track but no charging circuits.

Powerdynamo is a great compromise for the street but not cheap either.

How will the bike be used? Street/touring/track days? May help to decide on ignition to suit.
 

jpmobius

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Re: Yamaha rd350 road racer

I'll second the PowerDynamo system as a good choice. Personally, I like a Banshee system better, but it is a real PITA to implement as you need to build a Frankenstein crank to accept the permanent magnet stator and the ignition trigger does not fit inside a stock Rd case cover. The PowerDynamo system is nearly identical but is a much bigger hassle to adjust the ignition timing. It is fine once you do set it, and the charging/power supply is huge improvement over the old RD system. It is a bit pricey, but you do get a lot of hardware and can easily run with no battery as the charging system and ignition system are completely independent.
 

davedogg

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Re: Yamaha rd350 road racer

There's nothing wrong with points. Save the money and put it towards something else. BTW I have stock shocks in decent shape for cheap.
 

jpmobius

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Re: Yamaha rd350 road racer

Agreed. My driver RD is 100% stock. Points and charging. Coils are replica original - the OEM ones are crap and were when new. Runs like a top, but the charging system is anemic (even when tuned to perfection). The rotors are doomed to failure if you lean on the motor and are now getting scarce (ish), which is the best (IMHO) reason for swapping out to a more modern system. Points are GREAT on a mostly stock engine if you replace the coils and are ok with the normal tune up regimen.
 

Shoeman

Member
Re: Yamaha rd350 road racer

And I'll add that IMHO there is no real need to update to alloy rims. Put the money into shocks and upgraded swingarm bushings along with the tapered steering head bearings you already mentioned. Everybody's input on points and coils is dead on for a streeter. Some mild porting and head work along with the pipes you have will wake it right up for not much money, even with the stock carbs.
 

teazer

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Re: Yamaha rd350 road racer

And there are other opinions... I wouldn't leave points on anything more than lawn equipment. Maybe I'm just lazy and like the convenience of ignitions that are stone axe reliable and don't wear and change timing. I love to build and ride bikes, I just hate to do maintenance.

Alloy rims are nice but the difference is small on a street bike, agreed but they do look good when the cash is available for an upgrade at some future date.
 

Hurco550

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Re: Yamaha rd350 road racer

All good points to be taken into consideration. I really appreciate the feedback guys! The direction in my mind for this is to be in spirit close to a street legal race bike, but that said, I'm far from a purist, and I'm not the kind of guy that will spend 200 bucks for a period correct bolt or something silly like that. I also don't want to tune it past the ledge of reliability. I would like to come as close as I can to building the motor right the first time as far as porting ect, though I know a two smoke just lives for the day it gets to finally grenade on you lol.

For now, I think a good point was made on the wheels, but, I may possibly have a set coming to me for little to no coin, in which case I'll lace them.

The ignition is still something I'd like to do, as I don't enjoy fussing with points, that said, money will be spent on the crank and pistons first and I can always do that later on when funds build back up.

I'm not building this thinking that it will be a low budget thing and I know I'll have to spend some cash to make it right, but, I don't have a pile right now, so it will have to be done in stages.

I've been reading up on squish dimensions lately. I'm a welder and machinist by trade, so I'm planning on trying to tackle that on my own.

I have my eye on a crank, I'm trying to decide which banshee pistons to order, and sort the reeds. There are a number of piston options out there and I'm trying to decide where to go out which would best suit this build

Again, thanks for you input so far, I really appreciate the wealth of knowledge that has presented itself here already!
 

Hurco550

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Re: Yamaha rd350 road racer

davedogg said:
There's nothing wrong with points. Save the money and put it towards something else. BTW I have stock shocks in decent shape for cheap.
Pm sent
 

2_DONE_THE_TON

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Re: Yamaha rd350 road racer

hurco550 said:
I've been reading up on squish dimensions lately. I'm a welder and machinist by trade, so I'm planning on trying to tackle that on my own.

I have my eye on a crank, I'm trying to decide which banshee pistons to order, and sort the reeds. There are a number of piston options out there and I'm trying to decide where to go out which would best suit this build

Again, thanks for you input so far, I really appreciate the wealth of knowledge that has presented itself here already!
with the support of a good friend i managed to modify the squish on my RD and it makes a good difference to the performance before.
I used 350 LC pistons (i have reed valves), converted my stock RD carbs back to R5 specs (needles and needle jets),running 185´s mains with KN filter and DG pipes,it runs dang fine, just explored how easily those smokers wheel...its a blast ;-)
 

farmer92

Member
Re: Yamaha rd350 road racer


hurco550 said:
I've been reading up on squish dimensions lately. I'm a welder and machinist by trade, so I'm planning on trying to tackle that on my own.
Toroidal chambers too?
 

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