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

If you have been using those plug in step down adapters that are essentially 3mm shims that allow a 24mm axle to fit a 30mm ID bearing then yes.

When most people talk about the Praxis adapter they mean the one that sits in place of the BB30 bearings, in which case no.

Do bike24 have the 165 cranks then?

I hope so. I've just sent them 700 euros.

My bike has those Wheelsmith(?) push-in adapters that just slide into place over the axle.

You can use the existing bearings then, so there's no need to press some new ones in.

Well, I didn't know what the fuck to get so I bought the cranks (which hopefully come with the 109mm axle), the 104mm axle/bb kit and the crank extractors (since I figure I may as well own these if I'm going to be fucking with Hollowgrams now).

Also ordered the Hollowgram P2M.

Will need the Hollowgram spider tool at some stage and a video/manual on how to install these would be useful.

My credit card is very happy right now...

Awesome. Fingers crossed the experience gets less painful now.

Happy to help install and troubleshoot if you need it. You probably don't.

I need to fit my SRM to the pair I have on my CAAD10 so I could make a video...hmmm.

Do it. You know you want to.

I guess the trickiest part for me is the experimentation to see which axle might fit and then any spacing or chainline issues that arise with the axle choice. It's veering away from plug and play into plug and pray territory.

It'll be fine, it's very straightforward when you have it all in front of you, just make sure you have all the correct tools and a cup of coffee before you start.

And a photo of all the bits out the box/clean floor with no dremel, adjustable wrench or hammer within reach

And have the axles sitting in the freezer

@adsH it's the only crank I've ever had to hammer the axle in... and out. Well, rubber mallet anyway.

Well, I'll need to borrow a spider tool or find one to buy. Everyone seems out of stock though.
I also don't own a vice (well, not that kind of vice). Might be a job for the Bike Whisperer...

Hammer you say? Maybe it IS a job for me after all.

Anyone know how to estimate W'? And for any Golden Cheetah users, how does it calculate this? Just done a 20min test and it says my W' Expended (%) was 237 which makes me think it has woefully underestimated mine. In its model for this month it's 13.7kJ but in the past its been over 30?

It's it's any kind of help, I did a 20 min ftp and got these numbers
Average Power (watts): 261
Average Heart Rate (bpm): 171
Total Work (kJ): 313
Total W' Work (kJ): 20

Ah total W', didnt see that. I spent 19kJ, but the model says I have 13.7. How does that work? Shouldn't it increase it?

I had to google what w' is so I'm no use.

I just use the estimated W' value provided in the CP chart in GC.

I don't know how to actually test for W' but I imagine that having a fully fleshed out CP curve helps. I'm in the same position as you... last 10mile TT I spent 167% of my estimated W' suggesting that my current estimate is low.

I'm not too sure an exact figure really matters. My only real use for W' is the W'bal chart which can give you a good idea of how well a ride or interval was paced.

Just wondering if it being underestimated has any knock on effects on other metrics. I tried updating it manually but GC doesn't seem to take notice of it. Oh well.

I don't think it does, but I'm not certain. I think all the metrics are based off either CP or FTP.

Where are you trying to update it? Periodically I just read the numbers off the CP plot and manually enter them into the "power zones" tab on my athlete preferences... it seems to work for me.

Yeah I updated it in the same tab as you suggested. It just doesn't seem to care, still uses the old low number in the model:

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I've got a rotor 3d plus crank (p2m)
Can I swap the axle on this for a 24mm one? I guess not :(

Nope

Been there, the answer is no, as you suspected.

Why do you want the smaller axle?

BALLS. (Cheers @danb too)

Erm, no space in BSA68 for 30mm spindle with di2 cables in there.

Next Q.

Would that spinder fit onto a complete 3d crank? Or are they different spiders.