Wimmas Posted December 7, 2020 Share I need to get my pedal thread on my alloy left crank arm repaired preferably in the JHB area. It is totally stripped. Browsing the net it seems I need to get my hands on a pedal tap and thread insert / bushings. However, finding it or at least at an affordable price seems like a mission. Was hoping that someone knows someone who can assist at a reasonable price. Some of the local bike shops are saying they cannot assist and I need a new crank and I will also not be able to source only the crank arm - already asked the SRAM dealer in Cape Town. A new crank is going to set me back R3k which I am trying to avoid. I will already need to buy new pedals as well. Link to comment Share on other sites More sharing options...
MORNE Posted December 7, 2020 Share Bike shops are mostly filled with dumbasses. What you are looking for is someone to drill it out, tap it again (it will now be bigger) and put a helicoil back in to get the diameter you need for the pedal. That ironic part about a cycling shop saying it cant be done is this is exactly how the lefty forks work. They have a ‘sacrificial’ helicoil that strips out rather than stripping out the threads on your 25k fork. Any half decent engineering shop or a proper bike shop with a drill press or whatever can do it Mojoman, FirstV8, TheoG and 1 other 4 Link to comment Share on other sites More sharing options...
FirstV8 Posted December 7, 2020 Share Have a look at some of these https://www.google.com/search?q=helicoil+thread+repair+kit&oq=helicoil+&aqs=chrome.4.69i57j0l6j0i457.12749j0j15&sourceid=chrome&ie=UTF-8 Edited December 7, 2020 by FirstV8 Link to comment Share on other sites More sharing options...
Wimmas Posted December 7, 2020 Share I have watched this video, but getting my hands on these tools with thread inserts seem impossible. Looks like I will need to import and it is going to be costly. Thread inserts are sold in packs of 10 and cost around R950. A park tool pedal tap set will be another R1,100 from Amazon. Then I still need to find some suitable bonding liquid. Have a look at some of these https://www.google.com/search?q=helicoil+thread+repair+kit&oq=helicoil+&aqs=chrome.4.69i57j0l6j0i457.12749j0j15&sourceid=chrome&ie=UTF-8 I have found similar results on google but all our measurements are in mm, and it seems you need a specific thread size and insert, and the left side is more tricky. Not sure what will be the right pedal tap and thread insert from local suppliers like tork craft. Link to comment Share on other sites More sharing options...
DR ◣◢ Posted December 7, 2020 Share I have watched this video, but getting my hands on these tools with thread inserts seem impossible. Looks like I will need to import and it is going to be costly. Thread inserts are sold in packs of 10 and cost around R950. A park tool pedal tap set will be another R1,100 from Amazon. Then I still need to find some suitable bonding liquid. I have found similar results on google but all our measurements are in mm, and it seems you need a specific thread size and insert, and the left side is more tricky. Not sure what will be the right pedal tap and thread insert from local suppliers like tork craft.At those prices for once-off tools you are better off replacing the cranks with a set from Lyne Components. For interest sake. How did it strip? Link to comment Share on other sites More sharing options...
100Tours Posted December 7, 2020 Share Bike shops are mostly filled with dumbasses. What you are looking for is someone to drill it out, tap it again (it will now be bigger) and put a helicoil back in to get the diameter you need for the pedal. That ironic part about a cycling shop saying it cant be done is this is exactly how the lefty forks work. They have a ‘sacrificial’ helicoil that strips out rather than stripping out the threads on your 25k fork. Any half decent engineering shop or a proper bike shop with a drill press or whatever can do it I second all of the above, but if all you need is the left arm how about you just find someone (on the hub) who has installed a stages powermeter and want to get rid of their old left crank arm. just a question of what bb and what crank length you'll need. Shimano Dura Ace FC9000 Left Side Crank Arm | Bike Hub Shimano XTR new crank arm | Bike Hub Edited December 7, 2020 by 100Tours Link to comment Share on other sites More sharing options...
Wimmas Posted December 7, 2020 Share At those prices for once-off tools you are better off replacing the cranks with a set from Lyne Components. For interest sake. How did it strip? I am not really sure how it initially stripped. It's a brand new bike so I am not sure if the place I bought it at tightened the standard pedals too much, or if I ruined it. It might be that the standard pedals were tightened too much, and when I inserted the new pedals I just added to the damage. It is done now and let's just say it is my own stupidity. Lyne have been out of stock of cranks for a while now. Rapide as well. Not sure what is going on with their stock issues. I second all of the above, but if all you need is the left arm how about you just find someone (on the hub) who has installed a stages powermeter and want to get rid of their old left crank arm. just a question of what bb and what crank length you'll need. Shimano Dura Ace FC9000 Left Side Crank Arm | Bike Hub Shimano XTR new crank arm | Bike Hub Not a very common crank - It is a Truvativ Descendent 7k, DUB, Boost 175mm. Here is a link: https://www.sram.com/en/truvativ/models/fc-desc-7k-b1 Amazon sells a GXP left crank arm, but apparently it will not work on my crank. Here is a link: https://www.amazon.com/SRAM-Eagle-Crank-175mm-Black/dp/B0773M99VY/ref=sr_1_26?dchild=1&keywords=left+crank+arm&qid=1607366152&sr=8-26 Link to comment Share on other sites More sharing options...
Wimmas Posted December 7, 2020 Share I have found the right tools for the job on ebay and estimated costs are around R500. Problem is I don't know how long it is going to take for the package to arrive. If it goes through the post office, it will take three months if I am lucky: https://www.ebay.com/itm/PEDAL-TAP-THREAD-LEFT-9-16-x-20-TPI-ALLOY-STEEL-CRANKARM-CRANK-ARMS-BIKE-CYCLE/122850622360?hash=item1c9a77bb98:g:XjQAAOSw63FaKq6S https://www.ebay.com/itm/PEDAL-THREAD-INSERT-LEFT-CRANKARM-9-16-x-20-TPI-BUSHING-CRANK-ARMS-BIKE-CYCLE/122848758249?hash=item1c9a5b49e9:g:vScAAOSw4Z5aKTfb Link to comment Share on other sites More sharing options...
MORNE Posted December 7, 2020 Share Those are not funky tools...most car spanners worth their salt should have some. Helicoils and taps get used all the time in stripped out sparkplug threads for instance. Pretty sure BMC down here have the tools to do this. Maybe dont look fir a bicycle specific solution. It is a hole that needs a helicoil for a specific size thread. You’ll be surprised what the local mechanic is able to achieve. Edited December 7, 2020 by morneS555 PhilipV 1 Link to comment Share on other sites More sharing options...
MORNE Posted December 7, 2020 Share http://kingofthreads.co.za/?gclid=CjwKCAiAwrf-BRA9EiwAUWwKXlXycxfRX9uayVKjHyMd_gXWva7TXxLanOmFaqNhZ5dZ7D-H0-A9_xoC5wAQAvD_BwE http://autothreadrepair.co.za/ Just two... Link to comment Share on other sites More sharing options...
Dude Crush Posted December 7, 2020 Share Have you tried Richard (Customized Cycling) out in Fourways? He's quite a wizard so if anyone can get it right, I'm sure he can. Inbox me if you want his number. Link to comment Share on other sites More sharing options...
BaGearA Posted December 7, 2020 Share Most thread cutting tools and crap expensive for a damn good reason. Cheap tools will yield bad and probably dangerous results. Your pedals are one of two/three contact points to your bike. Don't do something to save bucks now and end up in hospital later. The stages upgrade option is best here. Doing it yourself with the right tools (cheap tools) will likely work but you're probably not a tool maker that has been doing this for ages and knows the pitfalls. If you stick to the repair option I urge you to take it to and engineering Co. This will most probably be around 1000 but I'd trust my life to that repair. FYI unior purpose made taps for bicycle cranks retail for above 2k per side, don't know what the torq craft ones go for but I wouldn't trust them worth a damn Link to comment Share on other sites More sharing options...
Graham W Posted December 7, 2020 Share Pop me a dm I can assist will take a day or two around R350-R450 TheoG 1 Link to comment Share on other sites More sharing options...
Wimmas Posted December 7, 2020 Share Have you tried Richard (Customized Cycling) out in Fourways? He's quite a wizard so if anyone can get it right, I'm sure he can. Inbox me if you want his number. Thanks! I have submitted my query on their contact form on the site. Most thread cutting tools and crap expensive for a damn good reason. Cheap tools will yield bad and probably dangerous results. Your pedals are one of two/three contact points to your bike. Don't do something to save bucks now and end up in hospital later. The stages upgrade option is best here. Doing it yourself with the right tools (cheap tools) will likely work but you're probably not a tool maker that has been doing this for ages and knows the pitfalls. If you stick to the repair option I urge you to take it to and engineering Co. This will most probably be around 1000 but I'd trust my life to that repair. FYI unior purpose made taps for bicycle cranks retail for above 2k per side, don't know what the torq craft ones go for but I wouldn't trust them worth a damn Agreed! Don't want to go the cheap route and regret it later, but if it is going to end up costing close to what a whole new crank is going to cost, I might as well buy a new crank. I'll continue to ask around and hopefully come right. It is still fine for now and the pedal still sits snug with no play, but it bothers me knowing the pedal is stripped in. I also want to go the clipless route, and I know once I remove the pedal it will have to be repaired, no getting around it! Link to comment Share on other sites More sharing options...
Acre Posted December 8, 2020 Share Just to add to this, the items the OP sourced on ebay are the correct items needed to perform this type of repair. You need a threaded insert and NOT a helicoil, helicoils are terrible things and will not conform to the bicycle specific pedal thread size of 9/16"x 20TPI. It isn't an easy repair if you don't have the correct skills and equipment. The setup needs to be correct so that the new thread created for the insert is perpendicular to the original hole otherwise you'll end up with a wobbly pedal axle when pedalling. Man how I wish I had my own workshop and the time to help people out in situations like this. I could do it through my work but then the cost to the company will be too high and the repair not economically viable. Link to comment Share on other sites More sharing options...
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