Cycling UK Forum

I picked up a new bike last week - a Merlin Axe7 Pro - and I absolutely love it it. I've ridden it daily for a week, mainly commuting, and I can't get enough of it.

However, yesterday on the ride home I noticed a very rhythmic ticking/clicking sound coming from the bottom bracket area. It only occurs when the cranks are being turned and the drivetrain is in motion, but it's immediate, and occurs around 6 times per rotation of the crank arms. The faster I pedal the faster it goes. It doesn't occur when pedalling backwards and happens when pedalling very slow or very fast in any gear.

Any ideas what it could be?

At some point it will go back to the LBS for its bedding in service, so I'm tempted to live with it for now, however, I'm curious about it and would like to know if it's something to be worried about...

it could be one of several different things; however it sounds like it is most probably the chainring bolts.

The bolts may be loose. If they are loose enough, they may drop out as you ride. At the very least just make sure that they are not that loose.

I bet they are not greased, too. I would remove each bolt (just the inner part), in turn, apply a little grease to the screw threads (both parts), and retighten them. It normally isn't helpful to grease the outside of the outer (sleeve) part of the chainring bolts, but grease in the screw threads helps them tighten correctly and also helps prevent seizure in the long run.

If you take it to the bike shop they will probably retighten them but not grease them.

In the short run you should rely on the bike shop (it is their responsibility to start with, plus there is a small chance that you might make things worse if you are not that familiar with bikes) but in the long run there is a choice to be made between being reliant on the bike shop for everything, and doing various service checks, repairs etc yourself.

cheers

I looked at a newish bike with a noise described similar to yours. It was quite slight so not always heard on the road, clicking, only when cranks went round forwards. Happened when pedalling with either foot unclipped and also when rear wheel was off the ground and the cranks were rotated by hand.

On the front mech there was a bit of clear plastic stuck on with markings for the height adjustment from the chainrings. This was partially unstuck and when on the inner ring the plastic rubbed on the inside of the outer chainring. The rear edge was unstuck, hence why when turning the cranks backwards the plastic didn't catch.

Removal of the offending piece solved the issue.

Any noise should be tracked down asap in case it is the start of something major.

Thanks both, I'll have a proper look at lunch time and see if there is any offending item causing it, or if the bolts may be a little loose, and report back

Like all good detectives should, keep an open mind. Bike noises can originate anywhere although your process of elimination is the correct approach. It can be anything from your teeth rattling in the cold to a chipmunk in your saddlebag. Good luck with this.

can't be! they're all hibernating.

i think that i am the worlds worst locator of noises. they're never coming from where i initially think. these days i try the last possibility first. it usually helps.

Check the front derailleur cable isn't touching the crank spider arms.

mig wrote:can't be! they're all hibernating.

if it isn't hibernating that would likely make it a Western chipmunk. On the other hand it could be an Eastern or Siberian chipmunk, feeling a bit cheesed off because you have woken it up with all this tiresome bike riding...

cheers

chris3vic wrote:I picked up a new bike last week - a Merlin Axe7 Pro - and I absolutely love it it. I've ridden it daily for a week, mainly commuting, and I can't get enough of it.

However, yesterday on the ride home I noticed a very rhythmic ticking/clicking sound coming from the bottom bracket area. It only occurs when the cranks are being turned and the drivetrain is in motion, but it's immediate, and occurs around 6 times per rotation of the crank arms. The faster I pedal the faster it goes. It doesn't occur when pedalling backwards and happens when pedalling very slow or very fast in any gear.

Any ideas what it could be?

At some point it will go back to the LBS for its bedding in service, so I'm tempted to live with it for now, however, I'm curious about it and would like to know if it's something to be worried about...

First up I think this is the single best noise description we've had...
Description of noise, and when it happens, with fast/slow forward/backward all accounted for...

6/rotation is what is interesting - if it was 5 I'd be instantly thinking that something is catching on spider arms/bolts.
It could still be a label or a bit of cable - but as brucey says it could also be the bolts that hold the chainrings on.
Other main suspects are the pedals - if you can pedal one footed (cleats/toe straps) that might help.

If you can manage to make it manifest itself when the bike is in a stand (or upside down) then that's always a good way to find things. Of course normally when the bike is on a stand everything works perfectly...

I once had a clicking sound coming from somewhere which seemed to stop when I stopped pedaling but only with my right foot at the top of the stroke,this went on for 20miles or so until I saw a small label on my new shorts flapping in the wind .
When my foot was at the top of the stroke the label was edge on to the wind and didn't flap

When I had a regular squeeky noise on pedalling, in trying to trace it (I thought it was chainset/pedals but might have been saddle) I also ended-up only "pedalling" on 1st left then right (i.e. other foot applies no load) and see if it is only one side. I did that to try and see if it might have been one or other side of chainset (and might have helped eliminate saddle a bit as you'd still have the leg motion).

Ian

Well, well, well....

Don't I feel foolish

Had a good look at the bike at lunch on the communal bike bike stand at work. Three of us couldn't see anything untoward but all agreed it was coming from the bottom bracket/crank area.

Turned the bike over, and...

The LBS had left a barcode label on the bottom of the frame. Sort of a plastic label rather than paper. This had worked loose, or became unstuck on the chainring side and it was just enough that it was scraping the chainring bolts on rotation. The angle the label was pointing meant it wasn't making much of a sound in reverse, only going forward. Peeled the label off and all is well I must have miscounted the ticks per rotation btw..

I feel like a right idiot to be honest, but it was impossible to see this label from top down or looking face on at the cranks.

There's a lesson here for me surely

By the way, big thanks for all the advice and tips. Valuable all the same!

glad that you're sorted out but how on earth had a chipmunk managed to stick that on your bike

Sufficiently good description that one of the top few suggestions had it.

Glad it's gone