Accidentally stripped crankarm thread

[Venod]

This is the repair required, you might find a LBS who will not rip you off and who have the tools.


View: https://www.youtube.com/watch?v=0pZcEV92gYc

 

[AliShah2020]

Sometimes you can get a direct replacement keft crank. Necer right crank only. A tap only works if no metal was lost in the botch up. It cannot replace material, only clean up the threads. We still havent seen a photo of the damage, therefore it is only speculation.

Hi Yellow Saddle,

I managed to get the pedals in the right way round, prior to your request to see the threads. I took it for a test ride; everything seemed fine but unfortunately when I started cycling at speed I felt the right hand peddle arm move a few degrees and is now at an ever so slight angle. I stopped cycling immediately so as not to cause further damage.

I am afraid if I take off the arm to show you the threads,I may not not be able to get it back in. I want to be able to gently ride the bicycle to another shop rather than carry the bike.

I think best option is replacement parts to be on the safe side. Thank you for your help and input to a newbie like me. Greatly appreciated.

 

[AliShah2020]

This is the repair required, you might find a LBS who will not rip you off and who have the tools.


View: https://www.youtube.com/watch?v=0pZcEV92gYc

Thank you venod. Greatly appreciated.

 

[Yellow Saddle]

Hi Yellow Saddle,

I managed to get the pedals in the right way round, prior to your request to see the threads. I took it for a test ride; everything seemed fine but unfortunately when I started cycling at speed I felt the right hand peddle arm move a few degrees and is now at an ever so slight angle. I stopped cycling immediately so as not to cause further damage.

I am afraid if I take off the arm to show you the threads, as I may not not be able to get it back in. I want to be able to gently ride the bicycle to another shop rather than carry.

I think best option is replacement parts to be on the safe side. Thank you for your help and input to a newbie like me. Greatly appreciated.

Fair enough. From that description, it is clear the crank is ruined. Deep breath, pay your money and get back on the bike.

 

[Gunk]

Worst case scenario about £112 for a complete replacement, it’ll be easy to fit and an upgrade (so not a complete waste of money!) If you can’t do it a good independent bike shop would charge no more than £30.

a bit more reasonable than the £300 you were quoted!

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/283586262538

 

[biggs682]

Easy mistake

 

[Jody]

Fair enough. From that description, it is clear the crank is ruined. Deep breath, pay your money and get back on the bike.

As above. I wouldn't bother trying to repair it given the cost for a new crank. £100 mistake. Order the new parts and move on.

You must have had to really work at it to get the wrong pedal wound in to an opposite thread.

 

[Sharky]

Just be aware that since Dave Wrath-Sharman died Highpath have not been doing much work at all (he was 50% of their machinists, and easily the most talented). Chris Bell also died a few years ago, leaving them a one man band and their website hopelessly out of date.

From what I hear they are still operating but their turnaround time is measured in months at the moment. If you're wanting to get out on your new bike then a replacement crank might be the best way forward, unless you're up to the job of helicoiling it yourself.

It was Chris Bell I dealt with. He seemed a nice chap. Found out later that my daughters MIL had gone to school with him!

 

[AliShah2020]

Worst case scenario about £112 for a complete replacement, it’ll be easy to fit and an upgrade (so not a complete waste of money!) If you can’t do it a good independent bike shop would charge no more than £30.

a bit more reasonable than the £300 you were quoted!

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/283586262538

Gunk I can't thank you enough for taking the time to share the link for me. I will order this from eBay now. That makes my life easy. I have been bamboozled looking for a replacement over the last 36 hours. So many websites, and no website is answering their phone or responding to email. So thank you!

Final question:
What is the difference between 50mm | 175mm | Without Ring and 53.4mm | 175mm | Without Ring in the image below please? I understand the 175mm is the pedal arm length, what is the 50mm and 53.4mm please? Small nuances like this made it difficult for me and I am keen to understand the significance.

Thanks for imparting knowledge.
😊

 

[Ajax Bay]

Suspect chainline, but maybe BCD?

 

[Jody]

Final question:
What is the difference between 50mm | 175mm | Without Ring and 53.4mm | 175mm | Without Ring in the image below please? I understand the 175mm is the pedal arm length, what is the 50mm and 53.4mm please? Small nuances like this made it difficult for me and I am keen to understand the significant.

Ajax beat me to it but it's for your chainline.

 

[Black Sheep]

Chances are a local engineering shop will have helicoils and one of the lads will fix it for beer money. Covid hasn't stopped engineering companies from working, it can't be done from home, but finding one that will deal with you with the associated Covid risk may be a bit harder (though I doubt it).

Many small independent motorbike garages (not the manufacturer dealership) are able to helicoil repair things, I just had a front brake component on my motorbike helicoiled for about £30.

Yes, a pushbike is not a motorbike, but same tools, doesn't take too long, I'd be surprised to be turned away - but google search for one, check reviews are positive and phone first, don't just turn up!

 

[Drago]

It was Chris Bell I dealt with. He seemed a nice chap. Found out later that my daughters MIL had gone to school with him!

I never spoke to him, but you're not the first to say he was a nice chap. Dave Wrath-Sharman made the rather splendid Highpath 29'er all-terrain cycles in the late 80's. He never sold many, probably because they were fearfully expensive, but they were something else, very sought after now. Dave was using his own model daily, right up until his death. Dave also made and modified Cleland frames for Geoff Apps, so highpath has a lot of significant UK cycling history behind it.

 

[fossyant]

Just get some new cranks - easier to get hold of than a repair and TBH, they are quite cheap cranks.

 

[silva]

I don't think it's that hard to screw left into righthanded/vice versa thread if it's steel (pedal) into alu (crankarm). Alu is no match for steel so clear loser hence no damage to pedal thread and all to crankarm thread. It's probably even possible to cut thread in alu alike tapping without the steel hardened alike real taps.