Need a new BB?

[Willam]

Think I need a new BB? if so could you please recommend one, and if I would be best getting my lbs to fit, I don't have a touque wrench or tools, willing to buy the tools (can't stretch to a touque wrench tho) if not to difficult.

It's fitted with a shimano fc-m590 decore 9 speed, the BB came with the chainset, got it fitted at the lbs 14 months ago, bike used for commuting 14 miles a day, cranks have started slipping when weight is put on them starting off at lights etc.

Looking for a reliable BB for commuting, strong too as I'm around 14-15 stone.

Cheers

 

[gbb]

A more likely reason for slipping cranks when pulling away is a failing freehub in your rear wheel. The pawls (ratchets) inside get worn or sticky and dont engage straight away, hence the sudden slip.
Check your chain and cogs for excessive wear as well, this can also give a similar sensation.
TBH, I dont think a worn BB will give you those symptoms.

 

[Willam]

A more likely reason for slipping cranks when pulling away is a failing freehub in your rear wheel. The pawls (ratchets) inside get worn or sticky and dont engage straight away, hence the sudden slip.
Check your chain and cogs for excessive wear as well, this can also give a similar sensation.
TBH, I dont think a worn BB will give you those symptoms.

oh right, just thought it was a worn BB, I'll check out a replacement freehub, cheers...might be a cheaper repair too with any luck.

 

[Cubist]

Or even more likely worn teeth on the cogs and/or a stretched chain. You describe yourself as a strong rider, and I bet it's worse when you stand on the pedals to accelerate? The BB won't cause what you're describing as @gbb says.

 

[bikeman66]

oh right, just thought it was a worn BB, I'll check out a replacement freehub, cheers...might be a cheaper repair too with any luck.

^^^ Agree with the above. Changing a freehub is easy enough, but you will need a Shimano (or compatible) cassette lockring adaptor, a chain whip, a large adjustable spanner and a 10mm Allen key. The lockring adaptor is basically a small hexagonal metal tool with profiled teeth on one end that will mate with the lockring that holds the rear sprocket cassette on to the wheel. With the back wheel off the bike and the quick release skewer removed, wrap the chain whip around a sprocket in such a way that when you go to undo the lockring in an anti-clockwise direction, the cassette is held still rather than just spinning. Use the adjustable wrench to turn the lockring adaptor. Remove the sprocket cassette from the freehub body and note position of any spacers there may be. Remove the axle from the back wheel by undoing the locknut and bearing cone on the non-drive side of the hub and then slide the whole axle out towards the drive side. Remove the ball bearings from in side the freehub and then using the 10mm Allen key, turn the hollow bolt located inside the freehub. Take it all the way out and then lift the freehub clear of the wheel. Source a suitable replacement (the best quality Shimano one you can afford basically) making sure it is the same length as the original, i.e for a nine speed cassette. Attach it to the wheel and tighten accordingly. Pack a good quality cycle grease in to the races inside the freehub where the ball bearings will run and pop in some new bearings. Worth doing the other side of the hub at the same time too. Slide the axle back in from the drive side, then screw the cone and lock nut back on the other side. Adjust the tightness until the wheel runs smoothly, but with no free play between the axle and the rest of the hub/wheel. Using a suitable cone spanner and the adjustable wrench tighten the lock nut firmly against the cone. Check the wheel still runs freely with no play. Re-fit the cassette, taking note that it will only fit in one particular way, corresponding to the grooves on the freehub body. Use the adaptor to tighten the lockring (no need for the chain whip this time), re-fit the quick release skewer and pop the wheel back on the bike. Job done. Probably looks like a bit of a job from the description above, but it is actually pretty straight forward. You'll need to make sure you have the right size cone spanner for sure. This is basically a very thin spanner which will allow you to adjust the cone whilst not getting in the way of the lock nut above it.

The tools probably won't cost any more than £20 and the freehub body shouldn't be any more than around £25. Give it a go!

 

[Willam]

^^^ Agree with the above. Changing a freehub is easy enough, but you will need a Shimano (or compatible) cassette lockring adaptor, a chain whip, a large adjustable spanner and a 10mm Allen key. The lockring adaptor is basically a small hexagonal metal tool with profiled teeth on one end that will mate with the lockring that holds the rear sprocket cassette on to the wheel. With the back wheel off the bike and the quick release skewer removed, wrap the chain whip around a sprocket in such a way that when you go to undo the lockring in an anti-clockwise direction, the cassette is held still rather than just spinning. Use the adjustable wrench to turn the lockring adaptor. Remove the sprocket cassette from the freehub body and note position of any spacers there may be. Remove the axle from the back wheel by undoing the locknut and bearing cone on the non-drive side of the hub and then slide the whole axle out towards the drive side. Remove the ball bearings from in side the freehub and then using the 10mm Allen key, turn the hollow bolt located inside the freehub. Take it all the way out and then lift the freehub clear of the wheel. Source a suitable replacement (the best quality Shimano one you can afford basically) making sure it is the same length as the original, i.e for a nine speed cassette. Attach it to the wheel and tighten accordingly. Pack a good quality cycle grease in to the races inside the freehub where the ball bearings will run and pop in some new bearings. Worth doing the other side of the hub at the same time too. Slide the axle back in from the drive side, then screw the cone and lock nut back on the other side. Adjust the tightness until the wheel runs smoothly, but with no free play between the axle and the rest of the hub/wheel. Using a suitable cone spanner and the adjustable wrench tighten the lock nut firmly against the cone. Check the wheel still runs freely with no play. Re-fit the cassette, taking note that it will only fit in one particular way, corresponding to the grooves on the freehub body. Use the adaptor to tighten the lockring (no need for the chain whip this time), re-fit the quick release skewer and pop the wheel back on the bike. Job done. Probably looks like a bit of a job from the description above, but it is actually pretty straight forward. You'll need to make sure you have the right size cone spanner for sure. This is basically a very thin spanner which will allow you to adjust the cone whilst not getting in the way of the lock nut above it.

The tools probably won't cost any more than £20 and the freehub body shouldn't be any more than around £25. Give it a go!

cheers really helpful but these are the wheels, they have cartridge bearings, does the above still apply and where can I get hold of the bearing cartridges?

http://www.bikeradar.com/gear/categ...eview-specialized-roval-traverse-al-11-39751/

 

[Willam]

Or even more likely worn teeth on the cogs and/or a stretched chain. You describe yourself as a strong rider, and I bet it's worse when you stand on the pedals to accelerate? The BB won't cause what you're describing as @gbb says.

Had the cogs/chain changed at the same time, will check them out, I also have a spare chain so will swap that,cheers.

 

[smutchin]

Had the cogs/chain changed at the same time, will check them out, I also have a spare chain so will swap that,cheers.

After 14 months of riding 14 miles a day (presumably in all weather?) it is definitely time to replace the chain and cassette.

If you fit the new chain on the old cassette, you might find the problem actually gets worse.

It's possible that changing the chain and cassette won't solve the problem, but it's worth doing anyway as they're both probably very well worn. If that doesn't help, then it's time to start looking at other potential causes (like a faulty freehub).

 

[smutchin]

Changing a freehub is easy enough,

Is it? Really? I don't want to be patronising to the op but from what he says, it sounds like he is pretty inexperienced at bike maintenance and this is not a job for beginners.

It's also very unlikely to be necessary in this instance.

 

[Willam]

Is it? Really? I don't want to be patronising to the op but from what he says, it sounds like he is pretty inexperienced at bike maintenance and this is not a job for beginners.

It's also very unlikely to be necessary in this instance.

Cheers, realized as I was typing how daft it sounded, will also swap the cassette too!

If that doesn't fix it will see if my lbs can service my wheels.

No offense taken, the most I've done is fit new gear cables and new brakes.

 

[smutchin]

No offense taken, the most I've done is fit new gear cables and new brakes.

I'm sure you'd be up to the job, but no point trying to run before you can crawl.

Fwiw, I've never had a freehub fail - it doesn't happen very often. It's far more likely to be a worn chain and cassette that's causing your problem. You can replace these easily yourself - you'll need a cassette tool (to remove the lockring that holds the cassette in place) and a chain whip (to stop the freehub spinning while you undo the lockring). Well worth having these items in your toolkit. Get them from your lbs - they'll make sure you get the right cassette tool for your wheels.

 

[Willam]

well changed the cassette and chain...still have the same problem!

Any way of pinning down what the issue is, if it's the freehub is there a test I can do, before taking it to my LBS to make sure, as funds are low and can't really afford to spend on getting the hubs serviced (if the LBS can even do them) if it's not the hubs.

 

[gbb]

Its not really possible to test the freehub, assuming you could strip it down to its component parts.
It might seem disappointing having spent on a new cassette and chain, but at 14 miles a day for over a year you've probably covered 3k miles or more...that's wayyyy beyond what id get out of a chain so it was well worth doing anyway.

 

[bikeman66]

well changed the cassette and chain...still have the same problem!

Any way of pinning down what the issue is, if it's the freehub is there a test I can do, before taking it to my LBS to make sure, as funds are low and can't really afford to spend on getting the hubs serviced (if the LBS can even do them) if it's not the hubs.

If the local bike shop can't service your hubs they'd be better off packing it all in!

 

[Willam]

If the local bike shop can't service your hubs they'd be better off packing it all in!

Just thinking getting hold of the sealed bearings may be the problem.