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Discussion Starter #1
hey, im in the final stages of building bearings for my swingarm. but ive got a problem i wanted to run by yous guys. i have to make the thrust surfaces that will carry the sideload, how ever much there is, on the swing arm. i have a needle bearing setup inside the swing arm, with an inner race that will extend out to the spacer/washer/bearing in question. but i need a thrust washer/surface/spacer for the swingarm. on the stock setup, its the bronze insert that has a flange turned on it that has those cups over them that hold the grease etc in. it also acts as a spacer to center the swingarm in the frame. since im using a seperate inner race, it doesnt have that flange on it. nor can it since it has to rotate in between the mounts in the bearings. so i need to make a spacer that will either carry that inner race, or have it contained inside or in between. in essence, a continuation of the needle bearing, but with a flange to act as the spacer, like the stock setup originally had. i thought about using the old brinze inserts, but ditched that idea. then i thought about buying some silicone bronze, but that shits expensive. so then i thought about plastic. i have a pile of teflon stock that i could make it out of, or delrin. the tensile strength i found for teflon is about 3500lbs. the tensile strength of delrin is about 9000lbs. i already made the parts in teflon thinking there wasnt that much a difference. but i looked it up after i got home and there is. so i guess my question is, think its worth remaking them from delrin? or is teflon good enough? remember, this is sideload on the swingarm at the pivot point. any thoughts?

jb? frank c?

jc
 

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Teflon cold flows when you put pressure on it. I'd make some more from delrin. I use delrin headed bushings in my swing arms when I replace the stock rubbers. The stock rubber actually seem to work fine. Needle bearing are over rated just like tapered rollers on the steering head.
FC
 

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Discussion Starter #3
whats cold flow?

so theres one vote for delrin.

crap, i knew i did it wrong.

jb?

modern sportbikes have needle bearings at the shock mounts. i guess thats over rated too. well, for a 40 year old bike, yeah, it probably is, but its still cool none the less. but id agree, a correctly adjusted set of ball bearings and swingarm bushings are probably fine. but im looking to get the most free play from the setup, and since its all ripped apart, why not? besides, if i went with all of your advice, id be riding cheng shins!

thanks for chiming in though. i appreciate it.

jc
 

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Needles ain't gonna hurt nuthin...but yeah probably overkill. Modern sportbikes use them cause they are pushing 100+hp through the swingarm pivot and it would probably just lock up if it was bushings.

I'd opt for Delrin too. The teflon likes to get an "impression" in it pretty easy. But to tell the truth I don't think there is a lot of side loading on these SA's. You rarely see much wear on the stock flanges unless they are full of grit.
JohnnyB

PS. I'm kind of neutral on the tapered steering bearings too. I onl use them when the stock stuff is trashed and has to be replaced anyway. Never noticed much of a difference between tapers and properly setup stock balls.



Edited by - jbranson on Jan 30 2007 11:32:01 PM
 

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Discussion Starter #6
jb, thats why i made them from teflon. because i figured it was minimal too. guess its back to the lathe though.


thanks for the input guys.

me
 
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