chain line issues advice welcome

swod1

On my bike I've gone from an internal bottom bracket to an external hollowtech 2 with the bearing on the outside of the frame.

I've never been happy with the chain line especially as this has messed up the front mech with the chain rubbing on the inside of it in the high gears even after a lot of tweaking.

I gave my bike a proper going over last weekend but I now wonder if I could change the spacer on the drive side and put it on the non drive side?

I've measured the frame and its 68mm which is I thought the reason for the spacer?

With the spacer on the drive side, the chain set sits out further from the frame than it used to and I would like to get this right as I'm looking at going single ring up front.

advice on what to change would be welcome.

The Rookie

Should be two spacers on the drive side, one on the non drive side.

Why not just sort out the front mech so it's in the right place?

swod1

The Rookie wrote:

Should be two spacers on the drive side, one on the non drive side.

Why not just sort out the front mech so it's in the right place?

I only put 1 spacer on the drive side as I was copying the bike shop when I replaced the knackered deore bb that came with the chainset, they had fitted it originally.

I did have the front mech in the correct place but it appears to look bent as its one of those that clamp above the chain rings are these weaker than the others.

But from reading the shimano tech docs the chain may rub on the front mech if in the highest gear or lowest big sprocket is this the case?

The Rookie

You should be able to avoid chain rub in all gears, but it's not always possible. You should never ever be riding in big, big regardless though.

Should have the three spacers stated earlier if it's a 68mm.