Friday, February 12, 2010

Setting up a double crankset

I have been asked about the crankset on my training bike many times and each time I explained it from the start - I guess I should put together a quick post that I can point to in the future.

The setup starts as an XT crankset (triple) that needed new chainrings. I don't use a granny ring and spend most of the time in the big ring so I felt a proper double setup would work better. With the big ring (a 42) where the middle ring was, I would also achieve a great chainline meaning that all the gears on the rear cassette would be accessible without having the chain at extreme angles.

I basically removed all chainrings from my XT crankset and bought the following 3 items.

Narrow chainring bolts (or single speed ones) for holding on my new big ring.
A 42 tooth 'middle' ring.
A 28 tooth 'granny' ring.

Then I simply bolted on the new 42 tooth ring where the middle ring used to live with the narrower chainring bolts, then the 28 tooth ring where the granny lived and finally adjusted the 'H' limit screw on the front derailleur so that it would no longer move to the old big ring position.

A post ride example of the setup

I've been really happy with the setup and spend much more time in the big ring as you can easily access the full 11-34 rear cassette.


Anonymous said...

52 is big /for ascending challenging hills such as Kilmashogue - hope your not out training on such a short chainset!

Mountain Goat.

Ryan Sherlock said...

52! it's not the 90s, I run a 42 :)

When it was dry last year, 42 was enough that I never left the big ring for 3 weeks.

Anonymous said...

Point taken, however there is a great benefit in training in a 52 than being building strenght.I've met amany a cyclist spinning on 40 somethings on the steeper climbs but when on a false flat (eg.past cruagh forest) they cant respond to a higher gear and the strenght that training on it brings.
I should point out that I usually have a double 52/47 using the lower on days when I'm tired but,it certainly is a real test to get up Kilmashogue lane on the 52 but the results are definitely worth it .worth a try or a challenge.
Mountain Goat
ps. A very good luck in the forhcoming season.

Ryan Sherlock said...

Thanks for the response, but are you talking about road stuff or offroad stuff? I spin out a 42x11 at about 45-50kmph... fast enough for pretty much anything off-road in Ireland. I don't even think you can get a 52or47 big ring unless you use a road crankset and make some modifications - but then you would be clipping it off things on a techy/rocky climb. (I have seen some folk do this to durace tripple cranksets).