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Bent rear axle!!!

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LongMooie

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Discussion starter · #1 ·
i know this is a problem once you start jumping these poor little 50s i think this is the 3rd one ive managed to tweek so whats the options does anyone make a stronger xr50 rear axle? i remember when i did the first one i spoke to a machine shop in the UK about making a titanium axle but he told me to thread ti you cant use a normal threading die it has to be rolled or something like that

if i remember right there was one company that put 3 bearings in the rear hub to help this problem i think it was BBR but i have a fast50s hub and dont wanna change now
 
#2 ·
itll cost you a lot to make that out of titanium unless you can do it yourself. I took it to Fastenal and they estimated 100-200... it would be a one off. The thing about the axle is it isnt a 12mm. The axle shaft itself is 13mm or so they estimate and then its machined down and threaded to a 12. So it isnt just a strait 12mm axle through it. I had looked into it because I wanted a 10-15mm longer one for a mod I was doing. GL lmk if you find anything...
 
Discussion starter · #9 ·
Ok im have two made from 4140 threaded both ends like the front axle

ill put it to the test and then ill be able to offer them for PM members

next would be Ti they said they can do it but didnt have anything in stock so i thought id try this option first
 
#12 ·
trtr013 said:
itll cost you a lot to make that out of titanium unless you can do it yourself. I took it to Fastenal and they estimated 100-200... it would be a one off. The thing about the axle is it isnt a 12mm. The axle shaft itself is 13mm or so they estimate and then its machined down and threaded to a 12. So it isnt just a strait 12mm axle through it. I had looked into it because I wanted a 10-15mm longer one for a mod I was doing. GL lmk if you find anything...
Click to expand...


OEM Honda axle is 12mm...the entire length. you must have some kind of joe-jitzu axle or something, or your Fastenal guy is a flunky (assuming thats who measured it for you).
 
#13 ·
LongMooie said:
i know this is a problem once you start jumping these poor little 50s i think this is the 3rd one ive managed to tweek so whats the options does anyone make a stronger xr50 rear axle? i remember when i did the first one i spoke to a machine shop in the UK about making a titanium axle but he told me to thread ti you cant use a normal threading die it has to be rolled or something like that

if i remember right there was one company that put 3 bearings in the rear hub to help this problem i think it was BBR but i have a fast50s hub and dont wanna change now
Click to expand...


BBR sells a stronger axle. also, make new (or have made) spacers with an inside diameter that is a snug fit on the axle. put some a$$ behind the ratchet when tightening the axle nut....dont be scared.
 
Discussion starter · #14 ·
fiveho said:
OEM Honda axle is 12mm...the entire length. you must have some kind of joe-jitzu axle or something, or your Fastenal guy is a flunky (assuming thats who measured it for you).
Click to expand...
Yup i second that there 12mm

and the machine shop called there contact and theres nothing off the shelf you can buy!

fiveho said:
BBR sells a stronger axle. also, make new (or have made) spacers with an inside diameter that is a snug fit on the axle. put some a$$ behind the ratchet when tightening the axle nut....dont be scared.
Click to expand...


there tight no worrys there

i think the problem is the drum brake as that seems to be where its bent or it looks to be, i didnt have a straight edge to put along it and forgot while i was at the maching shop so i might have to have that sleaved so it is snug to the axle
 
Discussion starter · #18 ·
zwieblekopf said:
some tempers of 4140 are stronger than Ti would be
Click to expand...


when they phoned the steel company they said the 4140 would bend past its sheer strengh and there was another one they cant remember the numbers but was close to 4140 that was stronger but would snap so for my application the 4140 would be best and they have 12mm in stock enough to make 3 but i said to just do two for now

im hoping to have them done today, with new flanged nuts im sure these are gonna be better than the stock 50 one
 
#19 ·
LongMooie said:
when they phoned the steel company they said the 4140 would bend past its sheer strengh and there was another one they cant remember the numbers but was close to 4140 that was stronger but would snap so for my application the 4140 would be best and they have 12mm in stock enough to make 3 but i said to just do two for now

im hoping to have them done today, with new flanged nuts im sure these are gonna be better than the stock 50 one
Click to expand...


throw that other one in MY bike while your at! ;)
 
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trtr013
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