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Discussion Starter #1
What would be a good upgrade for the forks on my 72 cb350 that would require little or no upgrades...? also, what tires do you suggest for the stock rims... ???

any help you guys have would be great.. thanks....
 

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the problem with the500/550 is the sliders are too short. the 750ss sliders are about an inch longer. so there can be less theoretcial flex. the 750ss trees also have a more favorable offset. at least for racing. it rakes a little more. around the street this might not be something you want though. i dont think the flex issue is going to be too much of one until it really starts to get pushed hard. and even then the crap assed chassis will probably be giving way more than the forks will, in an unbraced form. the frame really is crap. i also think the 750ss tubes are cleaner and nicer looking. they come with a trick cap that the 550/500's dont. so it looks cleaner. the clamps also dont have the big ugly handle bar clamp casting hanging out up there it has a rubber mounted bolt that has eyes on it similar to the brit stuff. so the top clamp is nice and clean. they are also a little more difficult to find. but still easily obtainable. either set-up will work with the same amount of effort. and you could use the 500/550 clamps, and the 750 tubes to get the best of both worlds for your street use. neither one is simply a bolt up job though. there is a little work needed to get the job done. its all pretty easy stuff and things you really dont have to have alot of tooling to do.

good luck
jc
 

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Neither job is hard... if you measure the inside diameter and outside diameter for the stem bearings you can do this job with out any machining. The 550/four trees are better and lighter. Joe you can tell me you can feel the flex difference between the two different types of lower stanchions. If you want rack, drive a chopper.

Aaron
 

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just because you cant feel it doesnt mean its not happening and not affecting you. right?? and like i said, the crappy frame w/o bracing is probably flexing more. then there is always the twisting forks is ok theory. if you go to computrack, they will tell you not to use fork braces on vintage bikes alot of the time. when i pull the front end off, i'll weigh them. unless you have each set kicking around. the 750 clamps are way more minumal than the 550/500. but the slider lenght could make up for that difference. they are probably the same withing a few grams. as you know, the honda bearings are not a typical off the shelf bearing shop item. they are freakish in size but pro-flo.com has a cross reference chart. the nice thing is that the 350/500/and 550 bearings are all the same. alot of the 750 bearings are the same, but not all.
the length of the stems is different though so either you'll need a spacer or you'll have to put the 350 stem in the other clamp and have it welded. then you can use the 350 bearing. that way you eliminate the chance of getting the wrong 750 bearing. unless you know for sure.
if you go to the 350mods forum, you'll see all of the stuff you'll have to do to get it all to go. im not going to explain it all again.

aaron, why do you think the 550/500 trees are better. and when you say trees, you mean front end right?? not just the tubes. i havent had a chance to open mine up and check the length, valving etc...but i know chris uses the 750 trees and so do alot of other fast guys. and there is a difference between the years for offset. the 78/79 are the ones that have the optimal geometry for race. did you notice what buff was running?? i didnt.

if i rake mine anymore, you'll start telling me to keep that fender i have!

jc
 

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I don't really have a preference... I was just fuck'n with you. I couldn't tell you the difference between the two. I have had a lot of experience with the 550 forks and they suited me fine. I actually hear to run the setup that you were talking about but with cbx triple clamps because they are lighter and have double pinch bolts. Jeremy could probably shed some light on this thread where he is currently doing this exact mechanical exorcism.

Aaron
 

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hang on, im writting that down, cbx triple....the down side to the 350 500 550 setups are the axle securing bolts. there are only 2 on each slider and i guess you want the setup with 4 bolts. i guess like the cerianis have. i dont know what came with that though. i know the later 900's did. i have seen older ones than the 900's. i actually felt a huge difference in the front end you gave me from the stock one. no more chatter and it definitely felt way more planted. i changed so many things though. it could have been tire too. but it makes a giant difference i handling. did you see what i posted to you in the racing forum??

turtle joe
 

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Discussion Starter #10
hey guys..
damn am I glad I found this site.. tons of great info and you guys are fast to respond...

ok, another question on fork swaps... I have available to me a complete front fork assembly with triple trees to fit a 2000-2001 Honda CBR929RR... do you think that would work out or would it be over kill....? Sounds cool though.....

keith
 

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I have a feeling the geometry is way off. but its really too modern for me to have any idea. bolt it up and see what happens. then let US know!

jc
 

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Discussion Starter #12
Joe,
Too tight in or too stretched out...?
also, I was thinking, the fron tire would be way too huge....

keith
 

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the cbr should probably have a 16" or did you mean width?? probably width. its probably fatter than the rear you'll end up putting on the 350. but that doesnt mean you still can use the forks. it'll probably take alot of machining. im sure the stem probably wont fit either. the new sport bikes only have a few degrees of rake and little trail compared to an old cb350. hence the need for steering dampers for most modern sportbikes. i really dont know for sure though. like i said before, its still too modern for me. the newest motorcycle i own is a 1982 model year.

jc
 

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quote:Jeremy could probably shed some light on this thread where he is currently doing this exact mechanical exorcism.
I have exorciiiized the demons!

yes, I'm using cbx triple trees on my racebike that currently has a cb550 front end. 35mm forks, width and offset are the same, stem size the same but the cbx stem is longer. I'll either be swapping stems or machining the cbx stem to work. the benefit comes from increased contact area between the trees and the fork tubes and dual pinch bolts on the lower trees. this all adds to more front end stiffness or less flex. also the lower tree is aluminum versus cast iron so it cuts a little weight
 

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and probably looks pretty, like me! its all so i'll stare in amazement as you gimp past.


dear forum,
i never though this would happen to me....oh, wrong "forum". anyway, i stopped to help a gorgeous stranded blonde woman wearing hot pants and a tank top. 85 degrees here today. she was driving a newer ginormous chevy suv. she had a tire blow out and didnt even know where the spare tire was inside the car. and get this, she's a nurse who works at the local hospital. i think jeremy mentioned something about nurses way back?? she was totally clueless, and totally a hottie. she pulled a towel out of the truck and was laying in the sun on the lawn next to where she pulled over while i changed her tire. so ive been in a good mood all day. im so easy.



jc
 
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