Measuring crank arm length

[Funtboy]

Hi all,

How do you measure the length of a crank arm? I need to replace my left hand one and want to make sure I get the correct length. I'm guessing that you measure from the centre of one 'hole' to the centre of the other 'hole'.

Am I right?

Cheers

 

[4F]

Hi all,

How do you measure the length of a crank arm? I need to replace my left hand one and want to make sure I get the correct length. I'm guessing that you measure from the centre of one 'hole' to the centre of the other 'hole'.

Am I right?

Cheers

Is the size not stamped on the rear ?

 

[Funtboy]

Is the size not stamped on the rear ?

Ah Yes, so it is.

Nothing to see here. Move on, move on.

 

[4F]

Ah Yes, so it is.

Nothing to see here. Move on, move on.

 

[Funtboy]

Here's a tougher question; where do I find a replacement? My googling skills are letting me down!

 

[4F]

What crankset have you got and what length are you looking for ?

 

[Funtboy]

Shimano FC-M341 175mm.

Do I have to get that exact crank arm?
I only need the left crank. Everything else looks fine.

 

[4F]

Shimano FC-M341 175mm.

Do I have to get that exact crank arm?
I only need the left crank. Everything else looks fine.

Well they key thing is to make sure the replacement part has the right taper fitting for the bottom bracket and of course the same colour and length. When I knackered mine many moons ago my LBS rooted around in his spares box and rustled one up which he sold me for a fiver. I am googling now

 

[Funtboy]

Okay, so I don't have to precious about the model then? Cool.

 

[4F]

How about this assuming your BB is square taper http://www.sjscycles.co.uk/product-...-FC-M442-Alloy-Square-Taper--Silver-15848.htm ?

 

[Funtboy]

Would I be able to get away with this...?

http://www.sjscycles.co.uk/product-Unbranded-Left-Hand-Crank-Arm-Alloy-Diamond-Hole--Black-14765.htm

(Black would match the rest of the crankset)

 

[4F]

Diamond hole fitting ? Probably best to phone SJS up and tell them what you have got and they should be able to tell you the best match. I have always found them to be very helpful.

 

[Funtboy]

Diamond hole fitting ? Probably best to phone SJS up and tell them what you have got and they should be able to tell you the best match. I have always found them to be very helpful.

Cheers, the one you linked to has a diamond hole fitting as well and it looks right to me. I'll phone SJS though. Cheers....

 

[Funtboy]

SJS reckon that'll do the job. That'll do me!