Having got my old p7 out for the first time in a while from under the stairs, it seems it’s been banged about by other flat dwelling cyclists, (or when I leant it to a mate for a charity ride) and a trip to the local shop (C&N Redhill- very good guys btw) advise that the chain is knackered, which I knew about, a shifter is knackered, which I knew about, but that the major issue is the middle chain ring is bent out of shape.

The crank is a Shimano STX-RC triple (compact?) (with a 4 bolt mounting) and the issue appears that the middle ring also carries the inner ring, and so both need replacing, and that they are not easy to get hold of new as stx-rc wasn’t around for long. To compound this, (I gather from the interweb) apparently the bolt spacing isn’t consistent on these with other sch

So I figure I might just try and get a cheap second hand crankset and ditch the stx-rc.

so, what can I get? What shiman serial no’s do I need? The bike doesn’t appear to have an external BB – does that mean that most of the newer shimano stuff won’t fit?

To be honest, I’m not that technical, but if anyone can tell me what to look for, or explicitly what *not* to get – then I would be grateful…

Cheers.

Alivio FC-M410/411 is the only modern Shimano equivalent, but any of their HT11 systems will fit using the supplied bottom bracket.I’ve actually got a brand new inner ring back at the shop, but can’t say if we have a middle without having a good search on Monday.(there was also another type of STX available with different rings again, both available at the same time. Confusion reigned supreme, and I believe was how we ended up with the wrong ring that’s sat in the spares box)

Thanks for the quick reply there –

So when you say any Ht11 will fit, with the supplied BB, that means that despite the present bike not having an external bearing BB, there would be room for that setup retaining a decent chain line?

It does seem odd to me that given the bike is 9 speed, which is still typically the norm, that a decade old crank is effectively a write off due to one bent chain ring that was designed to be replaceable!

Trouble is the bike ins’t worth that much, certainly not the £200 odd estimate for parts quoted. (They also suggested with rings and chain replacement that casette whilst on first glance seemed ok, would be worth replacing at same time – which is logical if you were doing the drive train “properly” rather than on a budget.

Alternatively, if you do find an inner and middle pair of rings, happy to deprive them from you for RRP as a cheap fix to a new crankset.

Surprised it’s 9 speed, the STX was either 7 or 8speed. If you do go for HT11, it’ll fit but it does have a wider chainline, which sometimes gives a bit of grief with setting up older type mechs. Depending on the amount of wear in your drivetrain, your bikeshop may well be right about changing the lot, but new rings alone are usually less likely to cause problems than either a new chain or cassette on their own. I’ll have a good scout around for a middle ring, I know we have the inner as I picked it up only yesterday.

Good news, we’ve actually got 3 middle rings in stock,rrp was £7.95, yours for £6 each.Call us on 02920371321.