Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

110bcd, 52x 36 standard rings.

Just casually checked the frame I'm buying and it's a PF91 BB, which looking at options would take a BB30 or GXP crank depending on which BB I fit? Or have I made a fopar?

is it a trek?

Canyon

Or have I made a fopar?

Definite faux pas. PF91 shells are 91mm wide, BB30 cranks are made for 68mm wide shells. It's possible that somebody might make some thin bearings to allow a 30mm axle to go into a PF91 shell, but it would need to be an abnormally long axle, the other lengths are 83mm for some MTB cranks and 86mm for BB386EVO road cranks.

A Rotor 3D+ might fit it, they're super long.

Yeah the Rotor and SRAM BB30ish cranks are long enough - but I don't think you can get a bearing to take them whilst still fitting in the comparatively small bearing seat in a '90 frame.

Fcuk, thanks.

Assumed it was standard gxp as I'm on my fifth Canyon....

It'll take a GXP crank. What's the problem? Bought a 30mm crank or somn?

but I don't think you can get a bearing to take them whilst still fitting in the comparatively small bearing seat

Rotor 4130 bearings squeeze a 30mm axle into a 41mm shell by using double row bearings, listed as suitable for BB86 with road cranks and BB89 and BB92 with MTB cranks. I have no idea whether the road axle is long enough to work with these bearings in a 91mm shell, although it seems very unlikely as the road spec. calls for just 0.5mm spacers each side with an 86mm shell

It can only be as wide at the standard that Scott and Giant use in their bikes, as once you've pressed in the bottom bracket in either of those frames there is no need to use any spacers when fitting a hollow tech 2 chainset. You can use the bottom bracket that Rotor make as you said you fit a Rotor 3D+, 3DF, Sram Force BB30 (but not Red), or a 386evo into those frames so it would be the same with the Canyon.

Tester has nailed it, the Rotor 4130 bearing will fit in your frame, but the cranks will only work if the axle is longer than 91mm (hence the name bb91)

Standard GXP cranks will work with a SRAM bearing or a set of Rotor cranks will work perfect as they're 91mm axle length - look at the Rotor Power or P2M

Rotor cranks will work perfect as they're 91mm axle length

If that's true, why do they only need 1mm of spacers to fill the gaps with an 86mm BB shell?

There is a rotating collar on the NDS crank which can take up a significant amount of slack.

There is a rotating collar on the NDS crank which can take up a significant amount of slack.

4mm worth? That's a lot of preload!

the 3D+ is designed to fit in a standard 68mm bsa shell, with the Rotor BSA30 cups, they measure 11mm each... overall 90mm + a little preload

To clarify I've bought a Quarq Riken R GXP crank, with a view that I'll get SRAM GXP pressfit bearings to fit into the Canyon Aeroad.

I also want to swap these cranks on to my winter bike as well.

I've asked Canyon to clarify and their response wasn't worthy of a repeat....but here's info they sent:

BOTTOM BRACKET BEARINGS
All frames (except Aeroad CF): BSA/BSC 1.370x24T, (right cup left hand threading!)
Aeroad CF: Pressfit BB 91 with 86.5 mm
Common cartridge bearings can be mounted directly into the bottom bracket shell of all models with high- grade grease. Observe the torque specifications of the bottom bracket manufacturer.

fit this: http://www.wiggle.co.uk/sram-bb86-gxp-pressfit-team-bottom-bracket/
job done!

The Shimano BB91 bottom bracket isn't 91mm wide though. It's 86.5mm wide for road bikes, as the Canyon e-mail says, and is effectively the same as BB86. BB91 is the Shimano model designation rather than a different BB spec. The bottom bracket will be 86.5mm x 41mm, so a SRAM BB86 GXP BB will be fine, as @Juggle says.

Thanks all

C 6months later... I have finally installed a power meter... Let's see if this changes anything.

You'll feel more inadequate a lot of the time.

Your bike is now heavier?

The frame doesn't arrive until next week!

And I'm going to wait for Sram Wireless

I'm in the process of getting around to sending back my Fixed Powertap to Paligap.

In the event they mess me around, I assume the 'worst case' is they offer to put in newer internals and have heard prices banded around of around £350 for this. It's a lovely wheel, Archetype with CX-Ray and I'd be reluctant to lose it but it has me thinking, for fixed, what are the other options (excluding pedals)?

Has anyone considered getting 4iii to stick a meter onto an omnium chainset? Is there a Power2Max option that anyone uses?