I am confused. I always thought that bottom bracket spindle length was determined by what crank you have. I am trying to order a replacement crankset for
my bike.
Here is the crankset.
The sales rep at bikesmart might be bikedumb. He said it doesn't matter about the crankset. It is the derailler clamp size (seat tube) that determines the correct spindle length.
I think it is more a combination of the two. I guess I need to measure the current bike and see what length is in it. I have a 2003 Trek 4300 with the same seat tube and I have a 122.5 in it. But that was the spec that the Suntour crank called for.
The chainline is awesome on that bike. The bike i gave the link to, is the one i am replacing the crankset on. It has always had too short of spindle in it since birth. I have never been able to get enough inward travel out of the front derailler to eliminate run in the inner/inner combo. That tells me the spindle length is too short currently.
I read somewhere that a Deore crankset requires a 113mm BB. Yet it seems like that is about what my current bike has. I guess i will measure it when i get home. So which should i get? 113 or 122.5 or something in between? He told me to get the 122.5 since that is what works well on my other bike. (same frame) Yet I am not convinced.