Sub-Compact Subcompact Cranks / Cranksets (Praxis Works Alba, etc)

Anyone know if you can run Praxis Works Alba 48/32 rings on a Power2Max 110bcd spider?

I can't work out if their special bolts will fit through the P2M spider:

Any other sub-compact ring options out there that might work with 110bcd P2M? Otherwise it's likely I'll need to change crankset which means ditching the P2M and going for Rotor INPower.

I'd hope that the small ring would fit on any 110 bcd spider/cranks, but I actually don't know. Sam at Stayer Cycles has a spare set of these rings and bolts, if you want to give it a try. Good training too, he's in Leytonstone...

They also machine relief on the spider to accommodate the chain's outer links.

To achieve that, Praxis Works screws the chainring bolts straight into the inner ring, dispensing with the usual nut, and machines a cutaway in the crank spider arms so there's room for the chain.

Source

So, that's almost certainly a no go. Balls.

So, next option is a powermeter that works with 3D+ cranks (or DA9000) that also somehow allows for smaller than 110bcd chainrings to be fitted.

I'm guessing Rotor INPower can't be retrofitted to my 3D+ cranks? Which means the cheapest option is an entire new powermeter crankset, which is clearly not that cheap an option. :S

Or the or alba chainset and Garmin vector 2's.

I don't want any pedal-based powermeters.

What about these bad boys?

Anyone know if FSA Adventure cranks will fit onto a P2M? Need to see if any P2Ms do direct mount rings..

http://www.gravelcyclist.com/bicycle-tech/review-fsa-sl-k-modular-adventure-bb386evo-crankset-subcompact-chainrings/

wont work, no spider, P2m is a spider, you are from Australia arent you? You should know about spiders.

I don't know how this direct mount shit works, thought maybe it bolts onto the back of the P2M as it's direct mount so shouldn't really have a spider at all, right?

What about one of these - Rotor REX?
https://www.power2max.com/en/product/type-s-mtb-power-meter-rex-1-set/

If the REX cranks attach to the P2M the same was as 3D+ I could just swap the arms out.

"I'm sorry but this will all not work. Our FSA cranks have a different technical interface, so a normal FSA crank will not fit our sensor and MTB cranks have a different Q factor, so the chain line will not work. The FSA version with super compact has a BCD of 120/90 and will be available in 2019."

2019

GAP YEAR!

I have no idea what you're talking about. The only gaps I care about are the ones between gears that I'm trying to reduce.

After much soul-searching I went for the 46/34-on-a-stock-shimano-cranks approach, plus an 11/34 cassette. Really nice, should have ditched the praxis thing months ago. Still could have done with lower gears on the nastier climbs/gravel/gravel climbs but hey.

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so 46/34 works? Only asking because Shimano advices against it.

When down shifting and on a small cog (say 5th or 6th from the bottom and up) the chain could end up slipping between the two chainring. But that didn’t happen when down shifting on a big cog (eg 3rd or 4th from the bottom) and might well be due to the derailleur needing adjustment, wasn’t enough an annoyance to warrant investigation. Anyway much, much better than with the alba crankset. Upshift generally fine.

I also really liked the gear range that 46 + 11/34 gave.

What's wrong with Praxis? I used 46/34 with mismatched rings and only had one issue with chainsuck which could've happened with most anything.

I could never get rid of chainsuck when down shifting on 48/32. That and the fact that their bottom bracket seem to last not long (in my case anyway), and the special tool required for installation, and no bb sleeve so the di2 cables will eat through the spindle, and the crankset developed a creaking that seemed unsolvable... I’m done with praxis cranks :)

If anyone wants to give it a try I’ve got a 48/32 Zayante that’s now unused. Comes with the problems mentioned above though!

Fair enough. I'm using a P2M on a Rotor 3D+ and a single Praxis ring (the other ring is a cheap French one).

sorry for being a n00b but whats a 'chainsuck'? and would I get it if I have clutched mech?

It's where instead of spaghetti, you're forced to slurp up bicycle chains by a large Italian man after he notices the tiny chainrings on your bike and laughs hysterically at them whilst luring you into his restaurant that's covered in Pantani pictures...

When you down shift, instead of falling completely on the small ring as you pedal round, the chain sticks to (or gets sucked by) the big ring in one point, and get jammed in the front mech if you don't realize what's happening early enough. Can lead to front mech totalling. It sucks.

Not sure if clutched mech would help. Fwiw I've tried running a longer and shorter chain (and also playing with the rear mech b-screw to have even more tension) and that didn't seem to change much.

It can normally be caught because you can hear it happening (and then you feel it) but when I did my doozy in Charlottesville I head headphones in coz I was busting a move to beat the Kiwi bloke.

Looking at setting up my Talbot with rocker dropouts with some chainrings for running a Surly dingle 17/19 cog. Hoping to have two front chain rings to choose from.

I've got DA 9000 cranks but at looking for 46 x 42 chainrings to run so chainlenth doesn't change much.

Does anyone know
1) If it is possible to run two such close chainrings
2) Where I'd be able to get some suitable shimano assymetric 4 bolt rings in said sizes.