Rotor cranks

To use that chainring you need either ROTOR 3D+, 3D30 and FLOW-cranks, as well with the INpower 3D+, 3D30 and Flow Pendants. i.e. 30mm axle cranks.

In order to use 30mm axle cranks in a BB86 frame you need the 4130 BB that rotor makes: https://www.bike24.com/1.php?content=8;product=34356;menu=1000,2,81

The balls in those bearings must be tiny if the OD is 41mm and the ID is 30mm.

Yep, not great. 30mm axle doesent really make sense tbh. And if 24mm axle shimano already makes the best cranks in the world.

yes, with 50/34 gearing... :) thanks for the advice!

Triple aint bad

I'm trying to fit a set of Rotor Flow cranks to my Cervelo P2c.

The P2 has a standard BSA BB shell and so this compatibility chart tells me that I need to use a BSA30 bottom bracket. I have fitted the BSA30 BB cups as described, and this diagram leads me to understand that no further spacers are required. However, when I try to install the cranks I encounter 2 problems:

1) The installation of the crank spindle is incredibly tight... far tighter than I would have expected from previous SRAM/Shimano installations, and certainly nothing like the installation videos I've seen online (although those don't seem to be using BSA30) e.g.1.
e.g.2.
. It took some unsettlingly vigorous hammering with a rubber mallet to fit the NDS crank, and even more effort to remove it again. Is this normal?

2) Once installed the spindle appears to be too short, or to phrase it another way, whilst the splines on the spindle poke out of the drive side BB cup, there is not enough engagement to allow the drive side bolt to thread into the spindle. The bearing preload system on the NDS is backed off fully and tight against the NDS crank arm so that is not the problem. This is obviously not normal but has anyone else encountered this problem before or have a solution?

A few weeks ago, I fitted some Rotors to a P3C using BSA30 cups and didn't need spacers.

The shaft did need to be knocked in: I seem to remember the instructions said to lube it.

All I can think of, is that the cups or the cranks aren't fully seated.

The cranks I fitted were the OE version they made for Cervelo, so the spider incorporated an 11.5mm spacer (for use with BBRight): Velotech swapped the spider for the standard width version. I don't think they make OE Flow, which would otherwise explain it.

Thanks, I think these cranks came specced as oe on a cervelo p5, but I can't see any spacers on the spider.

I had a search around and found this picture of a rotor spindle on slowtwitch where a p2m engineer confirmed that the spindle was the correct length:l, however mine seems to measure 106mm which doesn't seem right?

Unfortunately my computer broke this afternoon so I'm having trouble finding an official measurement for spindle length.

Does this mean that the spider IS weird? Alternatively is it possible to remove the NDS crank arm from the spindle and is it possible that the NDS crank has somehow been incorrectly fitted?

2 Attachments

Ah, I recognise that type of spider lockring. It's got an inbuilt spacer. The normal one is a flat disc with cut outs for the removal tool. That's not going to fit a BSA30 BB as it stands. You might get away with replacing the lockring for a standard one. I suspect you'll have to replace the spider as well though.

Right, just dug out my spare Cervelo spider and lockring and an old BSA30 BB. Found a spare 165mm Rotor 3D+ crankset. Happy days. The BSA30 BB fits in the recess in the spider taken up by the weird lockring, so I reckon if you can source a standard Rotor 3D+ lockring like this:

then you should be OK.

Your measurement isn't the same as the one in the photo as you still have the preload adjuster (the bit with the little bolt in it) fitted. And the NDS crank arm isn't supposed to come off.

Does this mean that the spider IS weird?

Yup, looks just like the the set I fitted pre-mod: see here.

Whether you could just swap the lockring, I don't know: the spider needed to be swapped from 5-arm to MAS anyway, so I didn't investigate and didn't bother asking for the old spider to be returned for comparison.

I don't have 100% confidence in their advice: when the cranks were to be fitted to a BB30 frame they told me I needed to do the spider-swap for it to fit, when actually it just needed the appropriate NDS spacer.

So perhaps you could just swap lockrings...

Excellent, thanks for the help both.

a) You are completely correct about the spindle length... silly mistake on my part. Measuring with the preload ring removed gives me a regular length of 110mm.

b) Regarding the spider lockring, I'll try to find one of the normal 3d+ variety and try that. The lock rings seem to be reasonably available from P2M and Velotech, but the only place I can find the tool is on the P2M site for $60!! Does anyone have one that they'd be prepared to lend me (I'm not in London so would need to post it back and forth...).

I really should just give up and buy a Miche Pistard Air, but the sunk cost fallacy has got the better of me.

I've got a 3D+ lockring tool. PM me your address and I'll send it over. Won't be until next week though as I'm off doing the GF Felice Gimondi this weekend. #boastpost

Enjoy! That remains my favourite Italian GF.

3d24 - any users? The Wiggle Q&A section say the spider is not removable, but I want to remove it so I can use with a power2max. Surely they ARE removable?!

Cervelo rotor bbright cranks: what do I need to do to these to make them fit bb30a?
Or is it much simpler to get standard 3d+?
Thanks

According to Rotor, 3D+ in a BB30A shell need 1x11.5mm and 1x0.5mm spacers on the DS and 3x0.5mm and 2x2.5mm spacers on the NDS.

Cervelo OE cranks have the 11.5mm spacer built into the spider, so you just need to omit that.

I fitted Cervelo OE cranks to a BB30 (not A) frame and my experience matches Rotor's chart (obvs).

I got the spacers from Power2Max, but I'm not sure if that would be cost effective now.

These are the cranks I bought. If you click on "22 sold", you'll see they're receptive to an offer: I paid £125 in Nov 2015. By now I'd imagine they're even more keen to shift them...

^thankyou!

tl/dr

Cervelo OE cranks will fit BBRight, BB30 & BB30A with varying combinations of spacers.

Any other BB and you'll need to fit a "regular" spider.

Cool cheers. Cannondale bb30a has been a utter pain in the arse. Wish I'd bought a 2nd hand caad10 than a new 12!!

Anybody got a spider lockring tool or know anybody who has one?

Which crank?

Really struggling to find various items in stock. Can anyone help?

3d24 110bcd 165mm
Q rings - 52/36

3D 24mm

3DF and BB86.5 .. Rotor says use 4130 BB .. would I need any spacers?

This frame.