[Closed] Stripped pedal thread on crank

A helicoil should fix it. Try some local shops to see if they've got a kit.

sometimes they can be rethreaded with a tap, sometimes you need an insert either helicoil or brass bush ( Hepco?) type

You can get a tap on EBay for £6, worth a go, though I've had mixed success .. once they go they often seem to strip again very easily. Helicoil kits are expensive (hopefully about to be proven wrong).

Oh, and the taps are left and right hand side so get the right one.

Oh, and the taps are left and right hand side so get the right one.

I think I'd go for a new arm in this case they aren't expensive for that crankset

£50 for a new arm, which seems expensive, given the whole chainset only costs £70

The universe is trying to tell you that you need to upgrade to a nicer chainset.

Nothing wrong with the Tiagra one, IMO.

"once they go they often seem to strip again very easily."

If its stripped rather than crossed then a tap doesnt to anything - thats why it strips again easy . If you have stripped the thread you need to add material.

Helicoils are great but just boshing a drill through on the old black n decker and throwing a tap at it unless your VERY lucky is going to result in wonky pedaling.

Take your time - find someone with and proficient in the use of a drill press and use the correct taper tap to give you the best chance, dont try and cheap out by just buying a second/plug tap

Realistically by the time you buy the correct tap (the expensive bit - 5/8" 24 TPI LH ) and a left hand helicoil - (a 5er) - your probably as well to buy a new crank arm SJS have them and are 50 quid

I'd just buy a whole new crank and keep the rings for spares.

Or alternatively sell them to me cheap, mine are getting a bit desperate now, but I'm too cheap to pay full price for them.

The right one is the left one in this case

LOL bad choice of words there!

Having had 3 or 4 GXP cranks go with varying degrees of success rescuing I'd agree with trail_rat .. I'd have thought any Shimano arm of the right length would be OK if you aren't too picky on looks, so check out the Bay. But for £20 difference I'd replace the chainset too. I did use striped and crossed interchangeably above when they are'nt the same issue, apologies - usually I find cheap pedals cross them on the kids bikes after seeming to go in OK for 25% of the thread.. a tap will help rectify that if you don't press on.

Try fitting the pedal from the inside face of the crank, this might retap the thread for you.

Thanks folks. I think I'll go for a new arm or crankset: I'm moving to Canada on Sunday and don't really have time to faff around with various engineering solutions.

Sjs cycles are doing l/h deore cranks, silver or black, 170/175mm £33.95

I have a helicoil kit

Unior, Cyclus and VAR do pedal thread inserts, you ream the crank and the fit a threaded insert.

Costs £15-£25 normally depending on the shop. Depends on the crank value if its worth it. DIY buying the kits was not cost effective last time I checked?

Try fitting the pedal from the inside face of the crank, this might retap the thread for you.

^^^ this.

Your LBS should be able to sort it if that doesn't work.</span>

You cannot retap a thread on material that isn't there, this will only work on a crank that has the first one or 2 threads damaged, on a stripped crank  (OPs own words) it's not happening.

New cranks.

Have a go with a tap.   If that fails I wouldn't bother with the helicoil especially with the reasonable cost of a new chainset.  Just see it as a pricey set of chain rings!

However, watch out for the hollowtech ones.  I've heard from a reputable source that they almost all explode at some point causing loss of limbs (and marbles) in the majority of cases.

😂

A colleague had a Hollowtech 2 crank (105 I think) sort of peel apart. Didn't believe him till I had the photo, still don't believe it was 'just riding along'. Been warrantied and returned, for the distributors amusement as much as anything.