Replacement chain set has longer crank arm - should the mechanic fix this?

[Flossy]

I just had the bottom bracket, crankset, chain and cassette replaced on my bike at a bike shop. I've got it home and realised they have used a 175mm crank arm when it was originally 170mm. It is a women's hybrid bicycle size medium and I think 175 is too long - I just want the same as before as it has always been very comfortable. Do you think I can ask them to replace this again free of charge? Or will I have to pay again. I didn't specify but assumed they would replace like with like...
Thanks in advance for any advice.

 

[rogerzilla]

They may be reluctant to do so if you didn't specify a length - cheaper MTB cranksets may come in 175mm only, whereas road cranksets usually default to 170mm. You will probably get used to 175mm within a few miles unless you have very short legs.

 

[Yellow Saddle]

It makes no difference whatsoever. Go for a ride and forget about millimeters. Drink a beer.

 

[Milkfloat]

Personally I would at least tell them and ask why they did it. You may need to adjust you saddle height if it was perfectly set before.

 

[Ajax Bay]

Do you think I can ask them to replace this again free of charge? Or will I have to pay again. I didn't specify but assumed they would replace like with like...

I think your assumption/expectation (like for like) is entirely reasonable. Unless you are taller than 5"10 (in which case a 175mm will be fine and it doesn't matter), I'd ask them to replace the one they've fitted with a 170mm crankset - this will take very little time (10 minutes) - and do this without payment. A 170mm crank is a sensible length for the bike (size and type) you describe (which is why it was fitted originally).
Before going back to them, ask yourself whether they asked you about freedom for them to select when you took the bike in.

 

[mickle]

What knowledge do you have which leads you to believe that 175mm is too long?

 

[sleuthey]

Some days I ride with different shoes which double the 5mm difference you will encounter from your new cranks. Unless you specifically asked them to fit a 170mm crank set I would just forget all about it.

 

[cyberknight]

i can tell the difference , having ridden 170s mostly i found 175s like i find the extra 5 mm like as if im having to exert the extra effort to get in around but then again its a sample of one
i would have expected the LBS to have replaced like for like or at least raised it before changing it and not informing you,If your not happy take it back

 

[Ming the Merciless]

Take it back. They will change free of charge.

 

[Ian H]

Some days I ride with different shoes which double the 5mm difference you will encounter from your new cranks. Unless you specifically asked them to fit a 170mm crank set I would just forget all about it.

5mm extra crank length with increase your pedalling circle diameter by 10mm (which may or may not feel significant). Thicker shoes will not affect it at all.

 

[midlife]

Thicker shoes reduces the radius of the circle your foot travels, I remember wooden blocks attached to pedals for little legs...... Well it was the 60's lol

 

[roadrash]

I wouldn't think they will change them free of charge if you didn't specify what you wanted , one question though,did you find out they are 175 by riding the bike and thinking ooh these cranks feel a bit long, or by measuring the cranks before riding it

 

[the snail]

Thicker shoes reduces the radius of the circle your foot travels

er.. no they don't

 

[rogerzilla]

Thicker shoes just move the pedalling circle up a bit.

 

[Drago]

What knowledge do you have which leads you to believe that 175mm is too long?

His inside leg is only 174mm.