Loose Race Face Turbine Crank

Hi Guys

Wondered if anyone can help with this. I bought a used YT Capra 2016 few months back and brought it to the bike shop to have it serviced.

Had my bottom bracket, cassette and chain changed. Soon after, my crank arm (drive side) started to come loose after a few rides so I kept tightening it with a 8mm torque wrench to 50nm. I eventually took the whole thing apart, cleaned it as much as I could, applied blue loctite, waited 24 hours but it didn’t work. When I put it back together, it seemed like the drive side crank arm didn’t fit snug and had play when fully inserted into the spline – do I need a new spline or new crank? Pictures below.

Those look like cinch turbines with the 30mm axle (rather than older 24mm axle turbine cranks). Do you have the preloader on the non drive crank? Doesn’t look like it in the pictures.

The driver side torque value is for the arm to spindle. The gap between arms and BB is taken up using the preloader.

Assuming the crank arm spline is fine you can replace the spindle if that is damaged.

The spindle looks mashed to me.

Jeffsy here with same crank. Odd, not once had it come loose ever.

Those little “crimp” marks look odd on the shaft but I can’t honestly remember if mine has them too?

Someone will know I’m sure.👍

Edit: Goiod point on the plastic preloader, I can’t see it either.

Those crimp marks aren’t right. I’ve had mine apart loads recently and have never seen those.

Just checked my spare axle and no marks.

They don’t all look the same length either… hinting that the ds crank has been rocking?

If they come loose and you ride it loose – the splines will wear, and they’ll never stay tight.

Those crimp marks are where the drive side crank has been rocking enough for the chain ring lock ring to make contact with the axle.

and brought it to the bike shop to have it serviced.

Had my bottom bracket, cassette and chain changed

back to the shop and get them to sort it

Sounds like they didn’t tighten it properly causing it to come loose and be damaged

Mine did just this, they’re knackered. Replaced them with Zee cranks which have a proper fixing 👍

Thanks guys! Sorry, yes, I do have the plastic preloader on the non-drive side. Picture below.

Correction on my initial post – on assembly, when I fully inserted the drive side crank arm on the spline it didn’t fit snug and was rocking.

I’m guessing a new crank would be a good shout? Was thinking of a SRAM X01 but the axle is 24mm. Could I just get an adapter or do I need to change the PF30 BB as well.

I was thinking of installing it DIY unless it’s better done at a LBS – have a 2 week waiting time at mine; too long for being off a bike!

https://imageshack.com/i/pm9blbqOj

I think there are BB adaptors available however have never used them. Isn’t the SRAM 24mm spindle different from a Shimano one as well (I’m assuming its a GXP spindle).

I’d be hesitant of using the same shop if you think they didn’t refit the crank correctly. As to DIY it’s not a difficult job, depends how handy you are.

Another crank option you be raceface Aeffect. These are a 24mm axle with a different mounting design and would take the double cinch spider your current cranks have fitted (if you wanted to stay with a double). However they could then easily be converted to 1x front of you went for that in the future. New they are around £80 from shops. There are definitely PF30 to 24mm reducers available.

Oh depending on the state of the rest of the bits I might be interested in them for spares.