road triple v mtb one?

[rouleur gentil]

In the process of building up a Condor Heritage, but stalled on the decision of what chainset to put on it. Rear is currently set up with a 9-speed 12-25 road cassette.

Current contenders are:

• Tiagra 9-speed or 105 10-speed road triple (10-speed should work OK and be a little bit lighter by virtue of being 105, I think?), 30/39/50

• Deore 9-speed M590 triple, 26/36/48

The frame's currently fitted with a Hollowtech II b/b, and I've already tried it with a compact road chainset; while it felt fine unloaded on the 34 ring, I had a feeling that with a bit of luggage and a slope, I'd be running out of gears pretty fast with a 34/27 (had a different cassette on it then!). I'd also like to use the bike for a bit of rough stuff riding.

Advice welcome (including alternative choices)!

[Valbrona]

It won't be long before someone comes on and says: "Oh, why don't you fit a 34t rear sprocket and and MTB rear mech?"

Smaller chainrings and triple chainsets are an altogether more common-sense route to lower gears, but I would point out that there might be a difference in chainline of about 5mm between an MTB triple chainset and a road triple chainset. Not sure how the Deore M590 fares on this matter.

Note that there are road specific triples out there, like a Stronglight Impact Triple which is 74/110 BCD. On this you can fit MTB-size rings. I run 26/34/42 rings.

Note also, that a triple chainset will need a rear mech with a longer cage than with a double chainset.

[rouleur gentil]

Just been browsing through old threads on this sort of topic, and lots of people seem to end up going round the houses before settling on a Stronglight/Sugino solution! Thanks for the tip. Also for mentioning the chainline issue, which I'd completely forgotten about.

I did think about the mountain-bike rear solution, and actually I've got a 9-speed XT rear setup on my MTB... might try that with a compact, just to see before I chuck money at it. That would mean putting the standard chainset back on my race bike, though. Oh Lord.

[Erudin]

Got the Tiagra 9-speed chainset/front mech on my Thorn Audax, really like it nice and stiff, just bought a spare from Ribble for £50. Run it with 9 speed mtb gears/LX hub on the back (32-11 or 28-11 cassette) and Dura-Ace downtube shifters.

http://www.bikeradar.com/gear/category/components/chainset/product/review-shimano-tiagra-fc-4503-chainset-8905/

[Richard]

I've got a 110 BCD road triple crank (from SJS) set up with 24/34/44 and a 12-25 rear cassette. Good close gears but low enough for easy climbing. Very rarely a higher top gear would be appreciated but usually it's the lower gears I want.

[mattsccm]

I use a 28/38/48 Stronglight triple with 10 speed 12/25. Not super low gears but it just got me up Rosedale chimney and my knees are screwed. Add a 28 rear and it would be great. add a smaller granny and it would be super but still giving big gears for lazy down wind riding

[Steve Kish]

My 22/32/42 with a 12-13-14-15-17-20-24-28 gets me up anything that I've ever encountered.

[rouleur gentil]

Quick update: I fitted an XT rear mech and an 11-32 combined with a 34/50 compact chainset, and took it for a ride yesterday afternoon. I think for audax riding or credit-card touring that's going to be fine; big gaps on some of the ratios, but not a problem unloaded. Probably easier than I need, actually, so I'm going to go for a compact/11-30 combination for day-to-day riding.

If I do ever do that fully loaded tour to the Pyrenees, I think a mountain-bike triple might be in order. I've seen this frame built up both with Deore and with XT, and it doesn't appear to cause any chainline problems.

Thanks for all the advice/comments.