Genuine question, do you run higher or lower double gearing with a 29er? Probably obvious to some, but I can imagine it might be harder to get on top of higher gears, but it feels easier to me.

I came from a 26er mostly using the 32 middle ring on my triple chainset, even when climbing, with a 32 9 speed cassette. My new 29er came with a standard double and a 36 10 speed cassette, and I’m mostly using the bigger ring.

I’m therefore also wondering if running a similar double on my 26er would have me pushing myself on a bit faster.

I’m hoping we can discuss this without having a one is better than the other debate.

i run a 36T middle, used to run a 32T… However when fitting the 36T it was part of the SLX Double/Bash combo, so i do have the option of the 22T front. However i’m yet to use it apart from 1 small drop onto it.

TBh i think it makes such a small difference to be really signficant from our reply perspective.

Oh, is 38/24 not a standard double then?

The 36 at the back of the 29er is like having a 34 at the back of your 26er, so it will feel a tiny bit easier anyway, if your used to using a 32t. (Assuming your 29er front is still a 32t).

Sorry, it seems I haven’t been very clear, I’m not riding round on the bottom gears of the cassette all the time. I normally reserve the last 2 or 3 gears for use with the smaller front ring on the double to avoid cross chaining. I do miss my gear windows though with I-Spec.

I’m currently running 26/38 with a 11/32 cassette – i only use the ‘big’ 38t ring in and around Bristol, but then i only use the ‘little’ 26t ring on trips to Wales – it all depends on the type of riding you do and where you live….

A 29er wheel is approx 10% bigger than a 26″ wheel so it’s effectively geared 10% HIGHER

so, to get the same gearing as a 26″ bike, you need 10% LOWER gear – meaning either a 10% smaller front chainring (eg 26″ 38t – 10% = 34.2 so a 34 on a 29er) or a 10% bigger rear sprocket (eg 26″ 32t cassette gear = 32 + 10% = 35.2 = 36t)

That sounds like an excellent ready reckoner clubber.

If I’ve got this right it would also suggest that if I’m happy with the higher gears on the 29er then I should be able to go 10% higher on the 26er with a double or cassette, or perhaps most cost effectively swap my 44 triple big ring for a 42 which I might actually use.

If I’ve got this right it would also suggest that if I’m happy with the higher gears on the 29er then I should be able to go 10% higher on the 26er

Yes though I didn’t really understand your bit after that.

Cheers for that.

I’m feeling ill at the moment, so maybe that’s why I’m not managing to be clearer.

My 26er is 9 speed with a 44/32/22 chainset and a 11-32 cassette. +10% on a 38/24 double would imply a 42 bigger ring or retaining the current 32 cassette, but swapping the triple’s 44 for a 42 would be cheaper and retain the bottom range currently available with the granny and cassette.

I think I’ve got it now. There’s no such thing as a ‘standard double’ but I think you mean you’ve got a 38/24 and 11-36 on your 29er and 22/32/44 and 11-32 on your 26″, right?

If so, 32/42 on your 26″ would be the equivalent of the chainset on your 29er but because you’ve got a smaller cassette on your 26″ bike it wouldn’t have as low gears as the 29er.

Yup, except that I’m thinking instead of getting a double for the 26er, that I can change my triple to 42/32/22 which would be much cheaper just buying 1 ring.

Cheers.

I’m not sure there’d be any point to that – why not just stick with the gearing you already have if you’re going to have a triple anyway?

If you don’t like your iSpec shifters, do you wanna swap?

What are they, SLX, XT?

Because I rarely use the 44 but the 42 equates to the 38 on the 29er, so hopefully I’d use it.

Too early before I’d seriously consider swapping XT I-Spec from Australia! I’m sure I’ll get used to them.

Actually that reminds me though, Shimano still warn against cross chaining with a double, but it doesn’t seem like it would be much worse than a single chainring to a 10 speed cassette.