I am coming to the conclusion I ‘need’ a power meter.

I think I’ve asked this before, but for shimano cranks, is there any issue with running an Ultegra or 105 LH crankarm wit power meter on a CX50 chainset. The interface should be the same I think and I can’t any differences in stiffness will really be noticable.

Are Stages gen3 and 4iii Precision much of a muchness? I.E. is it just a case of buy whichever I can find cheaper in sales?

i run a 4iiii 105 5800 arm on an 6700 ultegra chainset

that doesnt really help other than that if the interface is the same then you should be golden.

As far as I’m aware, 4iiii will work on any Hollowtech II crankset. Power meter tech is the same on all models, you simply pay more for the literal few grams of a left 105 5800 crank compared to say an Ultegra 6800.

https://www.probikekit.co.uk/cycling-power-meters/4iiii-precision-2.0-3d-power-meter-105-5800-black/11273315.html for £260 including a “free gift” of the 4iiii hrm is the best offer I know of.

Try Winstanleys for a good price, my 4iiii was just under £300. Bought one for me and one for my wife, both work fine. No issues connecting them to a Garmin. Crank arms are just black, so pick the cheapest. Come in different lengths, so dont buy the wrong size 🙂

As above it will work with any HT2 crank, MTB or road.

Pro bike kit do good deals and you can get a referral code from other customers to save any additional 10%. If you use mine I also get a fiver 😉

https://www.probikekit.co.uk/referrals.list?applyCode=JON-R1E7

Cheers all. Thanks, backs up what i was expecting. Need a 170mm crank which seems out-of-stock in probikekit unfortunately but will google away till I find whatever is cheapest!

As others have said, I have also used a 105 5800 Stages across Ultegra 6600, 6700, 6800, 105 5800, 5700 and Tiagra 4600, 4700 chainsets.

Whilst it will fit splines on a Shimano MTB crank, the last time I tried, Shimano road crank arms don’t have such a pronounced bend (so less Q factor) and likely won’t clear MTB frame chainstays.

I’m running a 105 , 5800 Stages 4iii with an Ultegra R8000 crankset, it’s fine. I do have a related query though, just bought a gravel bike with Shimano GRX on and was wandering if this would work ok as the Q factor is supposed to be 2.5 mm wider each side. Will it work or won’t it , I know I could just try it but if anyone could confirm I’d appreciate , thanks .

@alongo Yes, I ran a 105 crank with a GRX FC-RX600 for a while. I also continued to use a 105 mech with zero issues