Strange Noise from B/B or crankset

giantjason

I have a strange noise that appears to be coming from my crankset/bottom bracket.

Each time i pedal i get a clicking noise on every full rotation of the pedals?

Any ideas what this is?

If i need a new bottom bracket/crankset i will replace the whole lot. Is it a simple matter of un-doing the b/b and cranksets and replacing?

Cheers

Splasher

First remove your pedals and grease the threads and the flange and re-assemble. This is often the culprit where a click is concerned.

Otherwise it could be your chainring bolts or failing that a dry connection between your cranks and your BB.

If you do decide to change, it is just a case of undoing and replacing but you'll need tools to do that like crank pullers and various BB tools depending on what you've currently got.

giantjason

i have tried removing my pedals and replacing them but the noise is still there. i have also checked and tightened all the chainring bolts.

It only occurs when the pedals are under load and comes and goes.

Yesterday i did 25 miles off-road and did not hear it once. I washed my bike last night and then on my way into work this morning it started up again.

How would i check if it was a dry connection between cranks and BB and what is the best way to lubricate this?

deanvw

mine does the same, but i found out that it was the hub -not the bb, i found this out by taking the rear wheel off and spinning it and it made clunking noises

nicklouse

read the diagnosing drivetrain noises part of parktools. linky bellow.

skyliner

Tighten your rear QR skewer.

deanvw

it aint that, i think grit has got into my hub, i might have a go at doing a service to the hub thanks to parktools

skyliner

If it's only doing it under load, you'll need to get a new freehub. it'll be a shot pawl. The next step is a locked cassette, or zero drive.
It looks like you've got a M475 hub. If so, you'll need the C201 freehub. Cost about £18.

deanvw

nah its a promax

giantjason

no it is not the rear hub as it is still there when i change over to my skinny commuting tyres on seperate wheels.

i dismantled my pedals and cranks and greased them put them back together and it still sounds everytime when my left pedal is at approx 11 o'clock when pedalling along.

is there a way to lubricate the BB?

Splasher

Yep, which BB is it?

giantjason

i think it is a shimano BB. It is on a giant terrago disc 2005.

Underneath there appears to be a small hole in the frame directly below where the BB is.

Do i need to take it apart to lubricate it?

supersonic

The hole is for drainage, or to screw a cable guide into.

You need to remove the cranks, the bottom bracket, clean the threads and use copaslip or teflon grease om the threads. For info on how to do this, there is an article in park tools. Did you read the geberal clicks and creaks article? Could also be chainring bolts. Also if your axle is square taper, it should not be greased, its a dry interference fit.

giantjason

what tool do i need to remove a shimano bottom bracket.

My axle is the square taper type.

nicklouse

a shimano bb tool. and a crank remover.

have a look on parktools for tool info and how toos.

Al_Yates

You could also take your bike into the bike shop and get it "Faced off", This cleans the threads and gives them a perfect match then clean and grease. It will help...

nicklouse

Al_Yates wrote:

You could also take your bike into the bike shop and get it "Faced off", This cleans the threads and gives them a perfect match then clean and grease. It will help...

sorry to pull you up on this Al but you are getting two things mixed up.

you can have your bb threads "chased" which the cleaning and reshaping of the threads that is done with two thread taps. then there is having the bb shell "faced" which makes sure that the two ends of the bb shell are perpendicular to the center axis of the bb cup.