22/30/40 chainset on a 29er.

[Ray Young]

I am fitting my new 165 mm cranks to my 29er today which come with the above size chain rings mated to a 12/36 cassette. Going to be interesting to see how it compares to other set up's I've run - 22/32/44 and 22/36 on a 12/36 cassette. Anyone else running these ring sizes?

[slarge]

Not running those ring sizes, but on my commute today with 165mm cranks on the road bike it felt easier to go faster, I think I was spinning the pedals faster in easier or equivalent gears, and it seemed easier to pedal smoothly in circles. I am sure faster cadence and smaller chainrings means you won't see much difference.

[Bearbonesnorm]

Wasn't 22/30/40 something developed (dreamt up) for 29ers to allow for the higher ratio effect of the larger wheels?

[whonickedmename]

I've got this set up on my Genesis Longitude, it seems fine with 29+ as a 44 on the front would mean a fairly high gear inch combination (for me anyway!).

[ScotRoutes]

Coincidentally, I've just fitted a similar 165mm set of cranks to my 29er too. All my other bikes are 170 and my 29er was 175 so I was probably making things harder than they had to be. The extra 10mm of space betwixt saddle and tyre will be good for saddlebag clearance too.

[Gari]

Bizarre, I too have just put 165s on 2 bikes.
Some kind of group synergy maybe?!

[Ray Young]

Wasn't 22/30/40 something developed (dreamt up) for 29ers to allow for the higher ratio effect of the larger wheels?

Yes, by shimano.

I previously found that I rarely used the 44 ring on a triple set up so changed to a 22/36 2×9. I found that by doing this I was now using the whole spread of gears on the cassette. The only downside was if I shifted front rings then I needed a double shift at the back to maintain cadence. I reckon on the new 22/30/40 set a shift on the front will not need a shift at the back to maintain cadence and I also think that I will be using the whole range of the cassette in the middle ring when off road rather than just the bigger cogs.

I think I have always needed 165mm cranks for my inside leg measurement but never fitted them because I had read somewhere that they where very spinny and off road you needed the extra leverage of a longer crank. I have now learned that I am a natural spinner anyway so I'm not concerned about that. As for leverage I will just have to see on the ride I have planned for later today.
165mm length cranks seem to be easier to get hold of these days too with a much wider range of choice than previously.

A web search for users on this gearing brought up a few (American) threads. The naysayers who haven't used it basically saying that only a pussy (told you it was America) would need such easy gearing whilst those who actually use them think they are good.

I'll let you know how I get on.

[slarge]

Maybe this will have its own niche? 29er hardtail with 165 cranks. Another completely separate niche is the 26er hardtail with 165 cranks. Finally I am in the select few!

[Ray Young]

My first impressions of these gear ratios are good. I am certainly hanging onto the middle ring longer and using a bigger spread of gears on the cassette whilst in the middle ring off road, it suits my meagre power output very well so I am more than happy. Be good for loaded riding too.
I still need more time on the 165mm cranks to come to a conclusion about them. I didn't notice them being any more spinny but I have a high natural cadence anyway so spinning even faster would be difficult. I did however notice that after slowing down but not changing gear, turning the cranks over to get back up to my natural cadence again seemed to be easier and faster. One thing I did have to do was raise my seat height by 5 mm to counteract the effect of the shorter crank. With regards to leverage I didn't notice any difference.