Can't get crank off…. please help

Bike is a Planet X Pro Carbon. Bottom bracket is a GXP and needs changing but I just cannot get cranks off.

I was able to do it last weekend but when I put it back together I forgot to add the non-drive side washer which is what I think has caused the problem.

There’s just 1 bolt and I can undo that OK but the 2 cranks seemed to be fused together.

I’ve tried tapping it with rubber mallet and pouring boiling water of them. But they just won’t budge.

Grateful for your advice

I’d imagine they have a self extractor around the outside, and an Allen bolt in the middle, behind that?
If they’re like any other truvativ cranks I’ve taken off bikes and got rid of…
You’re undoing the innermost bolt, right? this pushes against the outer one and the crank comes off as you unscrew it.

Thanks for your repy, I’ve read about this outer bolt but as far as I can see its just 1 8mm bolt. Crank is a SRAM Rival.

like this?

8mm Allen Key ( IIRC ) in the middle of NDS Crank. The silver bit that is flush to the outside of the crank ( which you’d need a 12mm or something to get out, or I’ve seen them with holes for a pin spanner too ) is supposed to stay put.

SRAM RIval cranks have a self extracting bolt, when you undo the bolt on the non-drive side it should pull the crank arm off with it, usually you undo it, it is easy to turn for a couple of turns, then get s tight as it pulls the crank off. Is the bolt coming out, in which case you have something missing from the non-driveside crank

self extracting against a retaining nut

You do still have the nut ?

16mm hex

If it’s like a RaceFace Zeus, the outer “bolt” will be a self-extractor plate. It will have a left hand thread and a bigger hole so you can turn the 8MM crank bolt to undo and it then pushes against the self-extractor to pull the crank off the axle.

I’m missing something, quite literally. I’ve got the 8mm bolt but no 16mm one. Its quite obvious now that its missing 😯 Not sure how that would have happened.

Now what? New crankset? How am I gonna get this one off? 😥

You can get new crank bolt/end caps.

Old style crank extractor tool will do it. Or get another extractor bolt.

if there is no bolt holding it on (have i read that correctly?) stick a pedal on it and go ride round the block for a few laps and it’ll fall off

Did ride up and down the street hoping it would fall off but no joy. Will try again, if not I’ll get a new extracting bolt.

Just remembered I’ve got an old Truvativ crank in the garage, maybe I can use the self-extractor from that.

Thanks all for your help