Bottom bracket trouble - how worried should I be?

[SuperGalactian]

My 1995 Dawes Super Galaxy produces a creaking noise from the bottom bracket area - it has done since I bought it a few months back. In the process of trying to eliminate this noise, I have replaced the bottom bracket itself, triple chainset and cranks (well, I wanted to do that anyway). The cranks were torqued up repeatedly as they bedded in, and since then I have twice worked my way systematically over all the fastenings in that area, making sure they are torqued correctly. The noise can be generated at will by holding the bike fore and aft (it doesn't matter where I hold it, so the seat post and stem are not involved), placing a foot against the crank where it attaches to the BB and pushing. The frame flexes quite a lot (more than my other steel bikes, but perhaps that's not unexpected for a touring bike with a long wheelbase?), and a click happens. Repeat on the other side. Repeated clicks during pedalling = creak. There is a very small rust spot on the underside of the nearside chain stay where it runs into the BB lug, but the enamel seems sound all around it.

It seems to me that the creak must be the frame itself. How concerned should I be that it is going to fail catastrophically and leave me stranded somewhere? Assuming a repair is possible, when is the best time to do it? Now, when it gets unbearable, or when something fails?

 

[OldShep]

Sounds like you might have a hairline crack somewhere you’ve yet to find.

 

[T4tomo]

Sounds like you might have a hairline crack somewhere you’ve yet to find.

agree.

@SuperGalactian is it lugged steel frame? it might be that the brazing has failed at a lug somewhere - or a cracked tube. cracks are most likely near a frame join.

either is very fixable to a decent frame builder. Paint in effected area will need some attention afterwards obviously.

 

[Gillstay]

I think brazing on a lug too as something is clearly moving.

 

[cyberknight]

square taper bb?
in the past i have had creaking in the BB area and solved it by putting grease on the inside on the non drive side cup where the BB sits inside it .

 

[SuperGalactian]

square taper bb?
in the past i have had creaking in the BB area and solved it by putting grease on the inside on the non drive side cup where the BB sits inside it .

That’s a thought! I’ll give that a try and report back. However, because the creak has been present both before and after I installed a new BB, I fear it may not be the answer.

I’m already very fond of this bike after three short tours this summer in different parts of Britain. So I would want to get the frame repaired and re-enamelled if it turns out to be fractured. Any suggestions who to turn to for that, and what I should expect to pay?

 

[SuperGalactian]

This is what the BB area looks like. The rust spot between stay and lug is visible on the right in this photo. It looks dark thanks to a coat of Owatrol.

 

[Paulus]

This is what the BB area looks like. The rust spot between stay and lug is visible on the right in this photo. It looks dark thanks to a coat of Owatrol.
View attachment 818377

Looks nice and clean, but take the cranks off, and remove the cups and the BB, thoroughly clean the threads, apply a film of grease and reassemble. Many a creak has disappeared after this.
Also, check around the stays for any hairline cracks in the paintwork which may indicate a problem.
If this doesn't work, try removing the seatpost and cleaning and lightly greasing it.
Creaks can be very hard to track down.

 

[SuperGalactian]

Looks nice and clean, but take the cranks off, and remove the cups and the BB, thoroughly clean the threads, apply a film of grease and reassemble. Many a creak has disappeared after this.

But this is what I did when I replaced the BB and chainset. The creak was present before and after.

 

[midlife]

Used to despair with things like this when I worked in a bike shop. Pedals and headset maybe ?

 

[Bristolian]

I recently spent time trying to track down a creak on the non-drive side of my bike. I was sure it was the bottom bracket but turned out to be the pedal spindle bearings were running dry. Serviced the pedals and all is quiet again Just a thought for you.

 

[SuperGalactian]

At one stage I thought it must be the pedals, and then that it was my SPD shoe cleats. But no, both those are eliminated.

Headset is already re-greased and good. Seat post and saddle also eliminated.

I suppose if I (reluctantly) take the BB out again, and test the frame as described in the OP, that will settle the matter.

 

[ktmbiker58]

Is it possible to arrange to have the bike stationary with the back wheel locked so you can apply pressure to each pedal in turn to see if you can duplicate the creak?