FZR Bits on RD

[m in sc]

the longer lower case studs are what i used to bolt the cyls on however.. that was 20 yrs ago. now.. 

https://yambits.co.uk/rd350lc-cylinder-head-stud-p-84147.html

ac head bolts will work buuutt...
https://yambits.co.uk/rd350lc-cylinder-head-nut-p-77342.html

[sav0r (CL MotoTech)]

I stuck with the FZR stem but I shortened it. I converted to tapered rollers to accommodate.

[85RZwade]

Nobody tell him about TZ cylinders; he's in enough trouble already 

[m in sc]

the 250 ones not great on the street. 700 ones however... but... imho not worth it comparatively

[SmokeAddicted]

I stuck with the FZR stem but I shortened it. I converted to tapered rollers to accommodate.

Thanks, Chris. I have tapered roller bearings with the stock stem currently. Looks like those same bearings will work for the FZR stem (25mm top 30mm bottom). Looking forward to getting parts in hand.

[m in sc]

well. sort of. the taper on the stem gets wider before the bearing can seat. so you need to shorten, replace, or space it. you'll see when you have them both in your hand. i turned mine down on a lathe but still spaced the bottom beating race up on the stem a bit. i still have the fzr stem in, but if i were to do it again id swap it out w an rd one

[SmokeAddicted]

700 you say???

I feel like I could probably buy an RZ engine for what that would cost. Although, its TZ cylinders would be a better conversation piece.

I thought my dirt bike buddies were motorcycle nut jobs....until I ran across vintage 2T guys...

[m in sc]

one 700 cyl is 350cc so...

[SmokeAddicted]

Chris & Mark, if anyone else who's done it. Can you guys share some pictures of your FZR converted front ends? I'm most curious about how far the forks are above the top clamp.  I'm also interested in the clip-on situation, or if you used stock (FZR) clip ons.

Rusty, grimy treasure from today's haul

[m in sc]

heres a pic from 2013 . you can see how far the forks were over the top tree. with astock tree its even more, i made that one and it doesnt drop like an fzr one does stock. yes, you could put the clip ons on top. 2nd pic shows the stock fzr tree w clipons above it. this was from like 08 0r 09.

[sav0r (CL MotoTech)]

I run mine very much the same as Mark, specifically his second photo with the FZR upper looks nearly identical to how I run mine. It would be cool to machine a plate style upper triple, could drop the clip ons some but still have them high-ish. Maybe I will do that once we get through the race in July.

[IR8D8R]

Cognito Moto has RD400 conversion stems for various front ends. ...triple trees etc. Seems to be a primary focus for them along with hub conversions.

A bit pricey IMO, but billet parts usually are. 350/400 steering head dimensions are the same so the stems should be interchangeable. From my limited discussions with them they have the information to match basically any stem/tree or hub combination for custom orders and a flat rate custom stem price.

https://cognitomoto.com/search?q=Yamaha+RD+400+fork+conversion+parts&options%5Bprefix%5D=last.

IR8D8R

[SmokeAddicted]

Thanks guys. I appreciate the feedback/pictures. In my mind, I envision the finished product looking like the second picture. I have a left clip on, just need to source the throttle side.

I have a spare RD stem. As Mark suggested, I'm going to have the FZR stem press out of the triple, and the RD stem pressed into the FZR triple.

I believe all I need is new set of RD tapered bearings and it should be plug and play with the RD stem pressed into the FZR triple. Swing arm is next on the hit list

[m in sc]

you'll just need to mill in the sides, an thrn countersink the bearing in the arm a bit. i dont remember the actual dimensions but 6mm rings a bell...?

[SmokeAddicted]

I look forward to pulling it apart. It's an SRX 600 swing arm. Rough measurements between the stock pivot tube with bronze bushings, and the SRX pivot tube, it's so damn close.  Hopefully digging in within the next few days.