Dulwich Hill Bicycle Club

I currently have a 172.5mm crankset on my TT bike which is too big for my short legs.

I am looking for a 165mm crankset with a BB30 bottom bracket and 53/39 gearing. My budget is approximately $300 though I have noticed some good sales on various websites so may go up to $400 if it represents a good bargain.

I am tending to steer away from FSA and Vision as at that price range, their products get poor reviews. Shimano do not make BB30 compatible cranksets.

So the only other one I have found is SRAM Red but in 165mm they all tend to be compact and at standard gearing they start at 170mm. I've found one on ebay but that will not likely come with warranty etc.

Any suggestions/ideas?

Jo

Firstly, I guess I would question if you really need to go for shorter cranks or no... well at least that short! (maybe try some 170mm or 165mm cranks and see if it feels any better/different). In general shorter cranks are preffered on the track for fast acceleration. However, there is a pretty big debate over how much influence crank length has on power output and its not conclusive by any means. http://www.ncbi.nlm.nih.gov/pubmed/19771448

If you were to go for shorter cranks I would worry too much about reviews. There are good and bad reviews for a sorts of things all over the internet. The key issue I'd want to look at is what front derailleur your currently using. Increasingly groupsets are being built into systems with highly specified dimensions for optimal performance (ie, ramp features in the chain rings and the spacing between the chainrings). Usually things go bad when you mix and match systems. Believe me I've done it with a TA specialties chairing that said it was 10 speed compatible but never shifted properly on my ultegra cranks/derailleur.

You can put 52/38 SRAM chainrings on SRAM Red compact ... Trouty runs that. If you wanted to sell the original compact rings I'd be interested.

Also, I run SRAM Red cranks (bought 2011 model at steep discount from the hip shakers) with an Ultegra derailleur & the setup works great and certainly way better than the Original "Most" chainset did.

My road bike has compact cranks with 39,53 rings and it works fine. However your costs are going up.

Also have a think about foot velocity. 172.5*53 is about the same as 165*51.5 so you top gear isn't impacted that much by going to 165*50. Another way of looking at it is that 50/11 is higher than 53/12

The shorter cranks were suggested as part of a bike fit with the Body Mechanic. My road bike has 167.5mm and Blair said the 165mm would be a lot more comfortable on the TT bike.

Both BikeBug and MC Cyclery have said that they can get the SRAM red in within the week so I suspect they are from the same supplier (there is only 1 left). But BikeBug's price is $100 less than MC. As they both come with a 1year warranty then it is a no brainer. Oh, and the guy from BikeBug lives in Marrickville so has offered to drop it off at my house. How's that for service...

Stuart, looks like I will also be running a SRAM red crankset with an Ultegra rear derailleur. I'm sure this is very non-euro but as I can't spell 'summit' in French I can't see that it will matter.

If anyone is after a standard Vision crankset with a BB30 bottom bracket and 172.5mm cranks please let me know.

Just so you know, have read articles where it is suggested that the new SRAM Red Exogram cranks with the X-Glide chainrings work best, or are "optimised" for the matching SRAM YAW front derailleur. This derailleur in turn requires the new Red shifters.

My older 2011 model has no such issues.

That's a lot of expense and hassle for 2.5mm

7.5mm

Sorry, I interpolated your roadbike size with the TT in my internal narrative. I must also confess an acquired cynicism of crank length debates. Guilty on all charges, yer honour.