Hollowtech 2 bottom bracket question

[lulubel]

What might be the likely outcome if ....

A novice bike builder decided to install a hollowtech 2 bb and appropriate chainset, but discovered she didn't have the correct tool to tighten the preload thingy on the non-drive side crank.

Rather than taking the bike to her lbs, or ordering the correct tool, she decided to tighten it as best she could with her fingers, then give it a "little push" with the end of a screwdriver to get it a bit tighter.

She then proceeded to ride over 2,000 miles on the bike.

Purely hypothetical question, obviously

 

[RecordAceFromNew]

Sounds perfectly fine to me.

 

[ianrauk]

A 20p piece does for me.

But you're in Spain.. so the inequivalent size coin would do.

It's only for pre-loading the bearings anyway. Not meant to be done up too tight.

 

[PpPete]

Hypothetical novice bike builder is doomed ! DOOMED I tell you !

 

[lulubel]

So .... what might be the fate of the bearings if it was done up too tight? Or not tight enough?

Might they make tinkly noises? Or little pings? Or "chinking" sounds? For example.

 

[RecordAceFromNew]

Hypothetical novice bike builder is doomed ! DOOMED I tell you !

Aye. She is doomed because she relates said preload to said noises, while all non-hypothetical bike builders know Hollowsh*t 2 bbs will as likely make such noises as not within 2k miles, with whatever level of preload.

 

[lulubel]

Aye. She is doomed because she relates said preload to said noises, while all non-hypothetical bike builders know Hollowsh*t 2 bbs will as likely make such noises as not within 2k miles, with whatever level of preload.

Is that really correct? Does that mean I've identified the source of the noises, even though they sound like they're coming from the headset (which I've just replaced)?

I don't care if I have to replace it every 2,000 miles. I'd just like to be sure I'm replacing the right thing this time!

 

[RecordAceFromNew]

I don't care if I have to replace it every 2,000 miles. I'd just like to be sure I'm replacing the right thing this time!

To check your bb all you need to do is to slip the chain off and listen + feel for grinding and whatever noise when you spin the chainset. If you really want to isolate any possibility that it is the pedals you can always take the pedals off first.

 

[boydj]

It's a simple job to remove the cranks. You can take the bearings out or leave them in place and turn the bearings with your fingers which will let you feel whether there is any roughness or not. If they are the source of the noise, you should be able to feel something going on.

 

[lulubel]

To check your bb all you need to do is to slip the chain off and listen + feel for grinding and whatever noise when you spin the chainset. If you really want to isolate any possibility that it is the pedals you can always take the pedals off first.

There are all sorts of noises coming from that area when I spin the pedals with the chain on, but I hadn't thought about taking it off. That will be tomorrow's job, then.

(And changing the headset wasn't wasted money, in any case. The old one was making a lot of noise, and now I've cured that, I'm hearing all the other noises that it was drowning out. I think I should probably have bought 2 of everything when I built the Surly, but I'm learning a lot from this process!)

 

[GrumpyGregry]

the novice bike builder is going to die.






















one day.
eventually.
anyway.
But it'll be nowt to do with this particular piece of defective shimano tech.

 

[lulubel]

the novice bike builder is going to die.

one day.
anyway.
But it'll be nowt do do with this particular piece of defective shimano tech.

Thanks, Greg. You're a great help

 

[e-rider]

too tight and the cranks wont turn freely and bearing life will be very short.

Too loose and you will notice some 'play' and the bearing life will be very short.

Said tool only costs £3

 

[lulubel]

too tight and the cranks wont turn freely and bearing life will be very short.

Too loose and you will notice some 'play' and the bearing life will be very short.

Said tool only costs £3

I know it's very cheap. I just didn't know I needed it until I tried to fit the non-drive side crank. There's nowhere local I could have bought one, so it would have meant ordering online and waiting a week or so for it to come. I decided to improvise instead!

For the sake of £15 or so, I think I'll order a new bb as well as the tool, and just replace it.

Based on the amount of force I needed to tighten the compression bolt on the headset (which was more than I expected, and I obviously had the correct tool for that), I'm pretty sure I left it far too loose. Slight play in the cranks would also probably explain why my chain "clatters", despite the fact that everything else is tight and correctly aligned, and the gears are indexed properly.

 

[BimblingBee]

If its lasted 2k miles then its fine... However...

If your old bb was an internal one then getting your bb 'faced' may be an idea to ensure the new external bearings are parallel.This would help increase bearing life.