I've been trying to teach myself bike maintenance In an attempt to keep myself entertained during lockdown. Having tuned the brakes and gears of the whole families bikes I decided to try to try to replace my wife's dented front chainset.

I ordered what I thought was an exact replacement (same number of teach per chainring, same length crank), but my inability to correctly adjust the front derailleur makes me think there must be more to consider. I think the whole chainset sits to close to the bike as the primary issue is that I can't tune the inside edge of the derailleur close enough to the bike to stop it from rubbing.

My question is what else do I need to consider when choosing a replacement please?

Some detail about the bike and parts:

• The bike is a Carerra Subway Two.
• The original chainset was SA Suntour XCM Super Power Flow 48 / 36 / 28T
• My replacement is Shimano FC-M371 48 / 36 / 28T w/CG

Thanks in advance.

Tom

I believe you are referring to the crankset assembly. There really is no such thing as a front chainset. That's a significant downgrade in crankset quality it seems. Anyhow, the crankset should be matched to the right size bottom bracket for that frame. I believe your bottom bracket is too narrow for that replacement crankset.

You don't live in UK do you?

Did you change the BB too? Shimano cranks on other than Shimano's recommend and own brand of BB might sit with a different chain line than the Suntours on whatever BB they came with.

I was thinking exactly that a bit later. My apologies.

I got poked a while back for saying similar too when I ran into someone calling it a chainset.

So I've been sullied too!

Thanks for getting back to me, and for the pointers.

I didn't replace the bottom bracket no... but it is interesting to know that is a consideration. Also when you say the one I have chosen is a considerable down step in quality, do you recommend I go for a SunTour replacement?

(As I said, I'm quite new to this so I'm quite happy to accept I might not be calling things the right names too!!!!)

The simple fix for me was to get a new bottom bracket (10mm longer) and from that point everything fell into place. I also replaced the gear cable as I had shredded it a little in all my failed tuning attempts.