My Truvativ cranks are no longer self-extracting???

Went to quickly swap my 33t s/s ring to a 34t Works Component one, started take the cranks off – after the first few turns of the socket set there was a dull click and now nothing appears to be happening. Knocking the cranks off isn’t working because there’s still thread engaged (I just started knocking the non-driveside bearing out). I’m guessing I need some new cranks…

So two things:

1. How the hell do I get these out?
2. What’s a sensible choice for a 104BCD 1×10″ AM/enduro/trail/Super-D/XXXC-lite bike? Neither extreme weight weenie nor big budget.

Am I the only idiot who’s done this because everyone else has wisely switched to Shimano cranks?

what crankset is it – can’t envisage your problem as I’ve never had a truvativ one

It’s a Truvativ Stylo GXP. The centre of the axle is threaded, the outside is splined, and there’s an 8mm allen bolt inside the non-driveside crank arm that engages with the axle thread to pull the arm’s female splines onto the axle’s male splines. As everything’s al alloy and these cranks are four years old and were needing increasing torque to prevent wobble, I’m guessing one of the threads has stripped enough to not extract but not release…

I had a problem with some howitzers. The extractor bolt burst through the alloy cap that’s supposed to provide the extraction.

Once I’d completely removed the bolt / cap thing I just used a regular crank extractor.

Not sure it’s exactly what you want, but hopefully gives you a hint.

Si

Do you know if that alloy cap is replaceable? How did you get the bolt out?

internal BB unit, like old shimano octalink ?

presumably the self-extracting bit involves the actual crank bolt unscrewing against a “fixed” resitance barrier, that probably screws into the crank arm after you’ve put in the crank bolt ?

my guess is you’ve stripped the thread that this secondary part locates onto, so it can’t resist the crank bolt, so it can’t pull the crank off the axle

If so, and if you can get this bit out, you ought to be able to take the crank bolt out and maybe then you can knock the crank off

my guess is the bolt has sheared. you need to remove the bearing cap against which the ‘self extracting’ bolt bears (it’ll be a left hand thread) you’ll then be able to remove what’s left of the crank bolt and use a traditional crank puller to remove the crank arm from the thru-axle – hope that helps!!

edit, beaten to it 😉

No, normal HT2 BB – I have a Hope one with the Truvativ adapters on the non-driveside (the axle floats laterally on the driveside but is stepped down on the other side for lateral location between crank arm and the step in axle thickness).

Right, I get what you’re saying about the bearing cap, it seems its a 16mm hex with left hand thread. Now do I have an allen key that big?

Tighten the inner crank bolt back up a bit, to give you better access to the cap

(if it’s already knackered and you don’t have the right allen key, I guess you could bodge it out somehow – or even cut it out if you’re careful not to damage the crank)

It was a while ago, but if memory serves the cap had 4 small holes in it and I used two small allen keys in diagonal corners and a screwdriver between these to twist it out.. The proper way probably involves using a special dog spanner / pinned socket tool.

I didn’t bother replacing the cap, just means in future I need a crank extractor to remove the crank arms.

The aim would be to get the crank bolt out first, then try a crank extractor. ****ting it with a hammer is probably going to do more harm than good. 🙂

As I say mine was howitzer/husselfelt.

Looking at this vid:
http://on.aol.com/video/how-to-install-and-overhaul-a-truvativ-gxp-66770130?icid=video_related_6

Looks like you just need a bigger allen key to remove the extractor cap. Remove this first, then try removing the crank bolt.

I realise that at some point your cranks will need to come off but, surely a quick change would involve changing the ring without removing the crank. Or have I missed something?

It should be a 10mm allen key to remove the ally self extrator bolt/plate thingy, and almost certainly, you’ve cracked it. They’re not the most robust of things to be fair, but it’s not an issue, as said, just get it out then use a conventional crank extractor to remove the drive side arm.

I realise that at some point your cranks will need to come off but, surely a quick change would involve changing the ring without removing the crank. Or have I missed something?

I’ve yet to manage to remove a middle ring outwards over the spider – maybe I’m doing something wrong? If I get it past there I still have to take the (huge) flat pedal off to get the bashring and chainring past anyway. It’s normally very quick getting these cranks off…

LBS taking on the challenge of crank removal (it’s a 16mm allen key to get the cap out) and fitting Zee cranks (my Soul continues to become yet more gravity assisted…)

Had the bolt burst through the self extracting cap, had to dremmel out the remains then use a normal crank extractor.

Just seen a tip in getting that 16mm bolt out. Use a bolt with a 16mm head and a spanner to remove it.
http://www.parktool.com/blog/calvins-corner/sram-force-and-rival-group-service-and-installation

I seem to remember having a similar issue, think I used a crank extractor in the end (having extracted the self extractor…)

LBS actually had to cut the cranks out! The Zee ones are nice – they feel a lot stiffer but that’s no surprise when you compare the sizes of the crank arms. The BB bearings look much better protected from the weather by the shape of the arms and no stepdown adapter required in my Hope BB now, which should reduce annoying noises (it used to sometimes turn the bearing tophats).

Once again I’ve been surprised at how obvious the increase in stiffness has been when upgrading from an XC component to an AM/DH one, especially considering these cranks are on a Soul which is far from the stiffest frame about.