MattKahn

So this is my first post on this forum, I'm far from an expert at bike mechanics, I've been around them all my life and know how bolts work or how to change a tire, but when it comes down to the nitty gritty, I'm pretty much useless. So please, go easy on me (or don't, but at least help me out).

So I decided to finally change up some parts (bike has been sitting in the corner with a bent chainring o.O) on my State Contender II. I needed a new crankset so I decided to go with the Miche Primato Advanced Pista cranks. Did some research on fitting BB, and decided to just go with a Miche BB (conflicting reports but seems to come down to proper installation in general). Now here's my question, I contacted state and they told me the dimesions on my current BB are 68 x 103. Here in Belgium, I struggle to find a 103 Miche BB. Now I started wondering if the dimensions are the same, when using a different crankset. I figured a different crankset might extend further out and require a lengthier BB, if that makes any sense.

I'm on a very strict budget I can work with, and I already ordered one wrong part, and this stuff can be overwhelming for a newbie like me. So I apoligize if my question is downright stupid.

Brian25

The bottom bracket width goes with the crank arms. State is telling you what bottom bracket width went with the old cranks. If you could go bacwards in time.. I would have suggested truing the original chain ring or replace it if possible but not replace the whole crankset.

MattKahn

Thank you for your reply. Well, technically I can still go back in time, since I haven't yet ordered any of the parts that I'm planning to get. The thing is, this bike is almost 5 years old, and I've been beatin on this for the majority of that time. From the day I got the bike, the BB was making unhealthy noises, that kinda come and go on and off. Also I could never get a good chainline, leading to my chain falling off multiple times, snapping it in half, until it finally just ripped the chainring to shreds. So I figured **** it, I don't wanna deal with this setup anymore, let's just switch it all out. However if you have an opinion on why that might not be the smartest thing, please share. And thanks for the help, you really did help me out.

Brian25

You need to get to the bottom of this problem or you could / most likely will have the same problem even with a new crankset. I know a lot because I build track bikes/ have had to deal with chain line issues over the last 40 plus years. You need something fairly straight and about 50cm long that you can put up to the chainring (with the chain removed) and see if the line from the chainring lines up with the cog. It could be that the whole rear end of the frame is over to one side too much or the axle spacing may need changing. (which would be weird).