Which size chainset

[Franckster]

I've got a 9 speed, triple chainring set-up on my Specialized Tricross and the time has come to renew the middle chainring which has become very tired. However, what I'd like to do is take the opportunity to upgrade the chainset and the bottom bracket rather than just replacing the middle ring.

The chainset I've got on the bike at the moment is a cheapy FSA Tempo (50/39/30) with a square taper bottom bracket. I've been looking at the Shimano 105 triples in the same 50/39/30 size with Hollotech BBs, but they all seem to be for 10 speed set-ups. I've got a 9 speed rig on the back end. Does anyone know whether a 105 chainset will work okay with 9 speed when it's rated for 10 speed?

 

[PpPete]

It will be fine

 

[Franckster]

Thanks Pete. What's the difference between a 10 speed chainset and a 9 speed chainset then? Are the rings on the 10 speed just a tad closer together or something?

 

[gbb]

Thanks Pete. What's the difference between a 10 speed chainset and a 9 speed chainset then? Are the rings on the 10 speed just a tad closer together or something?

I don't think there is any functional difference, if you buy new chainrings, they fit 9 and 10 speed, they're often stamped as such. There's not a specific 9 speed or a specific 10 speed chainring. One fits both.
I'm waffling, but you get the idea

 

[Franckster]

Brilliant. Thanks guys.