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Grrrr


MikeCottTrials

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Its an old story really.

boy breaks profile,

boy buys replacements for profile,

boy can't get outer casing of old bearing out of freehub body,

boy buys dremel,

boy spends 2 hours grinding the case out

anybody got a better idea?

i tried hammering it out using a screwdriver as a wedge but it seems to be fused to the freehub body

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Try drifting it out equally a bit at a time, just hammering on one side will twist the race in the housing and you will never get it out. Tap it back into the freehub body to square it up again and try drifting it out again, tap gently and move the drift often.

If you can put you hands on a tungsten carbide burr then you can probably cut the old race out with it, a normal dremel grinding disk/burr will be pretty worthless, theyre expensive though. Cut a slot through the race and that should allow it to flex enough to easily drift out (it wont twist ***).

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Get a grinding stone for the dremel - I used a chainsaw sharpening stone for my bike. It allowed me to easily cut the races out of my suspension pivots when the same thing happened. This might allow you to directly pull the race out: http://www.enduroforkseals.com/id197.html - I got this set as I've done quite a few enduro bearing replacements on peoples suspension frames, hubs and BB's. The price isn't so bad when you convert from dollars... The only problem is the gaps in size between certain of the pullers means the particular bearing you have may not fit.

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If I've got the right idea from what your saying, you're replacing the driver bearings?

Good luck

My profile driver, not sure if they've changed it now like but it had a shoulder halfway down. The idea was to press one bearing in from one side all the way up to this shoulder, then press the next one in to the depth of the other bearings. Then do the same on the other side. This is why you cant just hammer straight through all the bearings, because this shoulder's in the way :/

The only 2 ways I know possible are to cut 3 slots into the bearing outer case, then it should fall to pieces. Or hammer from the otherside. This is seriously a ball ache of a job so be prepared to spend a while doing it :(

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Ive got a new problem now, with the casing out of the body.

The bearings seem to be extremely tight fitting, like im going to damage them if i push hard enough to get them in :o

any thoughts on this?

They should be a snug fit, you shouldnt be able to push them in with your fingers; I wouldnt be suprised if you needed to use a vice to push them in cold.

Is the freehub body aluminium? If so bung it in the oven for 10 minutes (at gas mark 4-5 or so) until its about 80 degrees C, a good temperature test is to spit on it, if the spit bubbles and runs off then its hot enough. The bearings should just drop in without any force then. Leave it to cool.

Once its cooled make sure the bearings are still smooth, if they feel at all notchy then the races have been compressed when it cooled and their either the wrong bearings or the freehub body is outside of tolerance. If they are notchy then theyll fail again very quickly.

edit: when I rebuilt my old profile hub on my bmx I think I used a lump of threaded bar with some nuts and washers to pull the bearings into the freehub. Think of it like a headset cup, you cant put those in by hand :)

Edited by forteh
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They should be a snug fit, you shouldnt be able to push them in with your fingers; I wouldnt be suprised if you needed to use a vice to push them in cold.

Is the freehub body aluminium? If so bung it in the oven for 10 minutes (at gas mark 4-5 or so) until its about 80 degrees C, a good temperature test is to spit on it, if the spit bubbles and runs off then its hot enough. The bearings should just drop in without any force then. Leave it to cool.

Once its cooled make sure the bearings are still smooth, if they feel at all notchy then the races have been compressed when it cooled and their either the wrong bearings or the freehub body is outside of tolerance. If they are notchy then theyll fail again very quickly.

edit: when I rebuilt my old profile hub on my bmx I think I used a lump of threaded bar with some nuts and washers to pull the bearings into the freehub. Th ink of it like a headset cup, you cant put those in by hand :)

Very true my friend.

Ok I'll try the oven thing in a few minutes. although im sure last time i managed to push them in some how.

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Assuming the bearings and housing are the correct size then its suprising how little expansion you need, its only a matter of microns :)

If you can get some threaded bar (a big bolt or plain threaded axle will suffice) and some decent size washers then that will ensure that the bearings are pulled in square. Dont forget to only push on the outside race, side loading on ball races destroys them very quickly so try to avoid pushing on the centre race on its own.

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New problem now!

I got it all functioning fine, i went outside for a few gaps all happy that i was riding...

a few gaps in the hub seized, after being taken apart i find a broken pawl inside.

anyone have a guess as to why this may have happened??? I have put my spare pawls and springs in now so i don't want to put it back together untill i know it won't do it again

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New problem now!

I got it all functioning fine, i went outside for a few gaps all happy that i was riding...

a few gaps in the hub seized, after being taken apart i find a broken pawl inside.

anyone have a guess as to why this may have happened??? I have put my spare pawls and springs in now so i don't want to put it back together untill i know it won't do it again

Pretty much nothing to do with the barings, maybe just worn, or something got in there when you was servicing the barings.

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Pretty much nothing to do with the barings, maybe just worn, or something got in there when you was servicing the barings.

yeah my thoughts are something must have caught the pawl. Im leaving it untill the morning now, but i reckon im just going to file the ratchet ring a bit and make sure its all clean in there

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New problem now!

I got it all functioning fine, i went outside for a few gaps all happy that i was riding...

a few gaps in the hub seized, after being taken apart i find a broken pawl inside.

anyone have a guess as to why this may have happened??? I have put my spare pawls and springs in now so i don't want to put it back together untill i know it won't do it again

just buy a fekin chris king will never ever let you down

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This seems a good place to ask now i'm in here. I got a Ti driver second hand in a hub (not for Profile but uses 6902s god damn). Anyway i got the same problem but never bothered to sort it out as wasn't intending to use that driver.

So Ti in the oven to allow the race to be removed? Or dremel or lathe, which could be sketchy. I ask because it's 1piece Ti.

Cheers :turned:

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This seems a good place to ask now i'm in here. I got a Ti driver second hand in a hub (not for Profile but uses 6902s god damn). Anyway i got the same problem but never bothered to sort it out as wasn't intending to use that driver.

So Ti in the oven to allow the race to be removed? Or dremel or lathe, which could be sketchy. I ask because it's 1piece Ti.

Cheers :turned:

It will need to be far hotter to get the ti to expand, you could try it though. Aluminium melts at about 660*C, titanium at 1660*C should give you a relative heat requirement :)

Think you might be better cutting the race out, if youre careful it shouldnt cause any problems.

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This seems a good place to ask now i'm in here. I got a Ti driver second hand in a hub (not for Profile but uses 6902s god damn). Anyway i got the same problem but never bothered to sort it out as wasn't intending to use that driver.

So Ti in the oven to allow the race to be removed? Or dremel or lathe, which could be sketchy. I ask because it's 1piece Ti.

Cheers :turned:

to be honest the dremel was shit hot, took about 2 hours though

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to be honest the dremel was shit hot, took about 2 hours though

If you can get a tungsten carbide bit for it then the time will be reduced dramatically, I reckon you could get through a bearing race in about 5 minutes :)

I think grinding the race is going to be the only real option with the ti driver.

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