Noise from crank (i think)

wurly

New Member
Location
Yeovil, UK
Hi people
Hoping someone can add some input to a slight problem i am having with my marin bike.
It started a couple of days ago. It started with a creak on one side when pedalling hard. When i got home i tightened up the bolts holding the cranks on to the square taper. They didn't seem overly loose, but creak went away.
However it started again! but quickly developed into a noise i can only describe as 'snick' not a 'creak'. By the time i got home the 'snick' became a loud 'crack' on every turn of the crank (again....by pedelling hard).
I have looked the bike and tightned the bolts again, (they have not loosened since last time they were tightened, this time i have really tightened them up.
The cranks do not appear to be loose at all, so i started looking elsewhere. I reset one of the pedal endfloats and checked the other, all is fine.
This is really difficult to trace as i need to be standing on the pedals for it to happen. I can hear it, but damned if i can trace it.
Any idea's?
Truvativ chainset
I should add, the bike is still under warranty, but seeing as i bought it from a shop miles away, it is going to be cost prohibitive to get it back to them i fear. So i would rather solve the problem before causing possible damage that may not be easy to fix at a later stage.
SDC10078.jpg
 

ASC1951

Guru
Location
Yorkshire
Being metal, bikes are buggers for transmitting noises - what my physio calls 'referred pain'.

A while ago someone posted a link to a brilliant website devoted entirely to diagnosing bike noises, but I didn't keep it. As forum search might find it, or someone more organised than me might post it again.

[Could be the chainring stack bolts. If you have drops, it could be the handlebar clamp bolts.]
 

TWBNK

Well-Known Member
Location
Wirral
I think it might be a loose bottom bracket, I tightened mine up on a Marin Toscana after about three months from new and The other halfs Novato after about 9 months.
 

Hacienda71

Mancunian in self imposed exile in leafy Cheshire
Could be a cracked BB shell, mine was doing this and it was a crack in the screw in shell. Check the BB tightness and condition of the shell.
 
OP
wurly

wurly

New Member
Location
Yeovil, UK
Ok
I have had another look. With me sat on it , brakes on, shoulder leaning on the wall, pressure on the RH pedal it 'cracks'.
Take my foot off the pedal reverse the crank 180 degrees, brakes on, pressure on the LH side.....'crack'.
So.....it is definately in/on the crank somewhere.
I tried to remove the LH crank without success (bastard is truely stuck). Without the right tools i guess my evening spent fixing this is over.
The bottom bracket BB you refer to, is that the whole crank assembly with bearings. Is what i am hearing, possibly the crank moving side to side in the frame?
 

Dr Jon

New Member
From past experience, with the same truvativ cranks and BB. The BB's are not great. For what it will cost for a new BB from shimano I would replace it. its an easy task and I am sure we can all help to inform you on how to do it.
 

rusky

CC Addict
Location
Hove
Dr Jon said:
From past experience, with the same truvativ cranks and BB. The BB's are not great. For what it will cost for a new BB from shimano I would replace it. its an easy task and I am sure we can all help to inform you on how to do it.
+1 I have a Marin with a Truvativ BB, it went after about 2500 miles. Got another & it was notchy & clicked. Seems quiet now though!
 

longers

Veteran
ASC1951 said:
]
A while ago someone posted a link to a brilliant website devoted entirely to diagnosing bike noises, but I didn't keep it. As forum search might find it, or someone more organised than me might post it again.
I've not saved the link either but have looked for it on here with no success. It is a very good guide.

My last creak was cured with a smear of grease on the bars where the stem clamps on. It sounded drivetrain related.
 

rusky

CC Addict
Location
Hove
 
OP
wurly

wurly

New Member
Location
Yeovil, UK
Thanks for the replies so far. Unfortunatley the link above is blocked from my work pc.
The noise coming from the crank area for sure

I've been searching the net. The BB on my bike is listed as Truvativ sealed cartidge, that is all the information i can find.
To replace it with another make i am going to need to know it's length, so i will definatley have to remove the crank arms.
It is disappointing to think it may have to replaced already with less than 500 miles on it. I thought the bike was fitted with quality parts....ah well!!

Later today i will order a crank removing tool and BB splined tool.
Just a thought, anyone from here in the Yeovil/Somerset area i can borrow the tooling from?
Not much i can do (apart from rebuild my old bike for getting to work) until i can remove the crank arms.
 

ASC1951

Guru
Location
Yorkshire
wurly said:
It is disappointing to think it may have to replaced already with less than 500 miles on it.
It could just be slightly loose.

Later today i will order a crank removing tool and BB splined tool.
Always useful to have anyway.

Not much i can do (apart from rebuild my old bike for getting to work) until i can remove the crank arms.
Jim Langley suggests that you can loosen the crank bolt and ride round - carefully, and with a socket wrench in your pocket - until it comes off.
 

redjedi

Über Member
Location
Brentford
My first thought was bottom bracket.

My old bike made a creak like yours that went away when I tightened up the crank bolts. It soon came back worse.
Turns out it was the bottom bracket, and it was just loose. I had replaced it a few week earlier.
Crank puller and BB tool are always useful to have anyway. Try just tightening it first of all. If it still doesn't work replace it. If you're not sure what size, go to a LBS and get them to give you the right size.
It shouldn't stop you riding it though. It'll be very annoying but shouldn't cause any damage if you use it for another day or two.
 
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