Stripped hub - feck!

Fuck and shit.

Tried to take off my 16t last night to put a 17t on for the London to Brighton. Couldn't get the thing off, so took it into the LBS and they got it off with a Park Tools Chain Whip (massive things, would've got anything off).

Problem is, I can't get another sprocket on.

The first 2 or 3 threads are simply not there, so it's only got about 3 threads left and there is a crossed thread right at the start of them.

So now, on the eve of the L2B, I'm 16t single-speed again (flipped the hub).

Can't be too gutted as I have new wheels coming next week, but this really pisses me off as I was looking forward to riding fixed to Brighton.

Anyhow, anything that can be done to repair it for the future? Or is it generally fucked and useless now?

Feck.

Just found the missing 3 threads.

They're on the inside of the cog I removed.

FUCK!

That was a Phil Wood sprocket too. Barely used (a few months tops).

It seems that:
[ulist]
[li]There wasn't enough grease.[/li]
[li]The sprocket and hub welded themselves together.[/li]
[li]The Phil Wood sprocket is stronger than the formula hub.[/li]
[/ulist]

FUUUUUUUUUUUUCK!

I couldn't remove my 17 when I tried. I'm worried about the same thing happening. I have a new Condor 17T sitting here now.. doing SFA.

Can you extract the bits of hub from the cog?

I don't think so. The fact that the thread was removed from the hub kinda indicates just how welded these things were.

I don't think I'm really of the patient disposition to sit here with a screwdriver and attempt to tap the threads back into the cog by gouging out the pieces of hub.

I've asked the LBS to get me another sprocket. This time I will liberally grease.

Cover the whole thing in oven cleaner repeatedly. Eventually it will dissolve the aluminium threads and your sprocket will be usable again. It might mess the finish up a bit, but hopefully it won't.

Oh, in that case I'll dig the sprocket out of the bin.

Do they make thread tools (tap & die, that kind of thing) that big?

it's those darn hubs innit

all the cheaper hubs seem to suffer with thread problems and track nuts and axle back nuts splitting

I would have been able to lend you my rear wheel, except goldtec are being gay with delivering an axle for the new rear I've built

Try just hooking at one end of the metal within the thread. Once you start to get one end out you tend to be able to pull the rest out in one go. I cant wait till more people make the bolt on disk cog, much better idea for street riding.. Anyone know of a uk supplier for them?

David did say there wasn't enough grease on the threads. Who's to say the same thing wouldn't have happened with a more expensive alu hub?

hippy Do they make thread tools (tap & die, that kind of thing) that big?

They do do a tap that big. A eruo bbtool for chasing out the threads would work. Same tpi and dimaiter. Die wise it would be done on a lathe.

The metal would actually be gone on the hub. All you could do would be to run loads of weld all around the hub, turn it down on a lathe and the redo the threads on the lathe.

I have BB taps.

running the correct one through the cog would clean it up.

welcome to pop round and try it david, if necessary.

I may take you up on that. I have a spare 15t and 17t cogs that I can put on my new wheels, so the cog isn't a priority.

I'd rather repair the hub for the new owner of the wheels. She was going to ride it fixed. So if I can fix the remaining threads by removing the crossed thread, then that would be cool.

it sounds like the hub is gone though..

it's flip-flop, so the freewheel side could be made suicide fixed. not ideal.

unless you can get a sprocket to go on the stripped side, maybe loctited. again, not ideal.

or is it a double fixed hub?

fixed/free

I like having the free-wheel, it's great for emergencies where you don't want to deal with back pressure or having to pedal. I'm glad I have flip flop :)

hippy, does the condor sprocket look well machined? i will want to replace the noisy stock sprocket on my pista when it has it's first service but don't know which one to get?

To be honest I bought it because they didn't have any of the cheaper ones in stock and I haven't checked it out other than taking a photo of it..

I didn't end up fitting it because I couldn't get the old cog off. Think it was £20.

the condor looks nice but i brought an EAI from hubjub in the end, looks nicely made but haven't fitted it yet

it was all going according to plan, got a 17t miche cog from condor and a chainwhip/lock ring tool, swapped the cog put on the lockring. rode it round a bit then tried to tighten the lock ring a little more just to be safe in case the cog had tightened more from pedaling... MISTAKE! the lock ring lost resistance and now just keeps turning. so i've stripped the thread right? unrideable? gonna need to buy new hub, so any suggestions? it was just the standard hub that came with the pista. how much does it usually cost to get a new wheel built up? would i be better off using this as a good time to upgrade? help please

What brand hub and lockring did you use?

was just what came stock on the bianchi pista

you'd know it if the cog 'tightened more from pedalling', the whole thing slips forward. or if not tight, it slips back if you skid. how much didd you tighten it?

if the thread has gone, i'm guessing you could rotafix the cog instead, not ideal, but i'm sure people said before that it's ok.

i tightened it pretty well with the chainwhip, was just trying to be safe and get the lock ring nice an tight. problem is cos it's a miche cog with the slot in adaptor thing it looks like you really need the lock ring to hold the cog there. the lock ring isn't spinning or anything and you can't just pull it out along the axle, but i imagine it's pretty dodgy

those miche carrier cog things are fucking shit, yes you need the lockring on for them to work.

check the thread on the hub and the lockring, hopefully it's only the lockring that's stripped

ah bugger. just went on what condor said when i went in the other day, though it seemed like quite a good idea. the thread on the hub is what doesn't look quite right. if it's totally stripped will there be nothing left? this is my first (and at this rate the last) attempt at mechanics. wanted to try and learn how to do stuff myself, learn and save cash. looks like might be more expensive this way!