You are hereForums / By Discipline / Mountain (off road) / MTB Gear / Chainring bent

Chainring bent


mrptl's picture

By mrptl - Posted on 18 August 2013

What do you reckon (photos attach), a bit of hammering repair will hold? or I better replace?

Tags
wal's picture

use a large shifter to hold and carefully bend back into place.

Replace? depends how fussy you are...??

hawkeye's picture

What he said. Keep an eye out for cracks.

mrptl's picture

Cheers, I will give it a second chance and look carefully for cracks. If it breaks, well I better be not far from the carpark Eye-wink

mrptl's picture

Tried yesterday with a pair of those

but with all the strength I've applied it didn't move.

If I want to replace this, do I have to get a new crankset? or I could only replace the chainring (will I need to get the crankset out (and go on youtube to learn how to do this))?

Matt P's picture

Ive got a 42t that has around 50km on it.

It should be a very simple replacement. Just undo the 4 bolts and slide over the crank arm and pedal.
Just make the the front mech has been moved over to little ring to give you room.

wal's picture

Try again but with a shifter... a big one.
Take it off and put it in a vice.

How did you bend it??

freddofrog's picture

A pipe wrench? No no you need a mallet. Place it on a wooden sheet, teeth pointing down, and hit. I have straightened rotors this way. If using a normal hammer use a block to protect it.

Or here's a left field idea, place it between two wooden planks and drive over it.

jeffmtb's picture

Geez replace it before you hurt yourself .
They are not normally that expenive, and there is an offer of another above.

I love working on my bike to fix stuff but you need to face the fact it's gone to bike heaven.

mrptl's picture

Will try with a hammer in between pieces of wood, and will avoid using the car Smiling

Did this while trying twice to pass over this big log, and failed badly both times.

http://youtu.be/O5I4L1bN28A (go to 3m32s)

Seems the repair stand I'm about to buy will become handy!

Scottboy's picture

Ir will need to be put in a vice with a piece of wood either sides of it preferably ply wood

Barnsy's picture

Its not worth the dodgy shifting and potential for injury if it goes again mid ride. As much as you try you'll never get it factory straight.

hawkeye's picture

I did that to a chainring once on my late and unlamented Mongoose Tyax HT, and while I never got it factroy straight, a shifter spanner or three were good enough to get it close enough to change consistently and give no trouble. Eventually it was upgraded to a better chain ring, secondhand.

Unless you're in the habit of track-standing on your chainring a la Chris Akrigg in A Hill In Spain, I'd doubt you'll break it, but it is still worth monitoring if made from alloy. To expand on my earlier comment, I would replace it eventually, but the spanner(s) will get you out of immediate trouble and back riding for now.


http://youtu.be/fohPU3pDpFU

mrptl's picture

Ok, will give a chance to the spanner. Need to go and get a bigger one.

And just in case I need to replace it, I counted the number of teeth on my chainring this morning… and it I had 44. Is that possible? I couldn't find specs on it to confirm.

freddofrog's picture

44 is pretty common but do you even need it anyway? Many people, just ditch it and replace it with a bash guard. You might miss it if you do lots of road riding but out on the track you never use it, at least I never did.

mrptl's picture

I was considering when upgrading to a better quality crankset (XT), to have only 2 gears. Do you then still have the same sizes chainrings?

freddofrog's picture

Yeah I do though most others don't but it doesn't bother me. I'm yet to run out of gears going down a track (and that's with only 2 rings) and appreciate granny gear going up them, especially steep technical climbs when I'm already buggered. All our tracks are twisty single track so if you're mainly riding fire roads I guess that may be different.

On tarmac I do run out of gears going downhill but it's not a road bike so who cares.

hawkeye's picture

What he said.

I have 24/38 on my Scalpel and so far it seems fine for local terrain. I like having the bailout gear for the steep stuff and I only ever run out of top end on the road.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Best Mountain Bike