So should I just forget about the keyway and slather it in 638?
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Man avio gears have a keyed pinion. I used sk3 (shocker). Round shafts no key. One side is just 680. The other has my hacked keyway. Still solid after lots of ks
Clean with a clear spirit. I used contact cleaner but rubbing alcohol or isopropyl will do. Smear the shaft and drop a touch inside the pinion/pulley and leave for at least 24. That’s important 24
Edit. Thats the stuff just a different temp rating
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Righto sweet. Also got sk3s for 12/33 belt drive. Will try just the loctite to start with and if it fails i will reassess.
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Let me say like this. In the last 4 month of 2019 I lost 2 motor gears due to loctite 648 not holding strong enough. Unfortunately I do not have space for set screw or key way. But I would always consider one of both options if you can.
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Pretty sure the pinions have a grub screw, it’s the dicky ho 12t
Andy is going full torque. My set ups are not as low.
Emtb is always going to be the real test.
Emtb is always going to be the real test.
If you have a grub then flat the shaft. Thats piss easy. The above was not
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Nah, you just drive like a pussy 
but seriously, I think with a belt drive loctite only could work pretty good. If it’s a belt drive without idler than it will work for sure as the belt rather will slip than rip of the pinion.
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It’ll have an idler. But 12/33 isn’t massive torque.
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I ride like the silver surfer. Like a GOD
Seriously though your set ups will always put more stress on the drive gearing regardless of gears or belts. Mine are pretty high compared and its only my gear drive that’s full loctite.
That set is 3.75.1
Thats my lowest. I like speed. See first line
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Thats the one I’m using. Can’t say much about long-term reliability, only have it for like a month. I think it is important to have good coverage, it is best if you can turn the pinion/sprocket on the shaft by hand. This way you can twist it on and around and feel how the loctite distributes and the pinion nicely floats on it all around. Then leave it for at least 24h with absolutely no load or force on it, better 48h. This is important, otherwise you will have microfissures.
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If there is one thing that esk8 has taught me, it’s patience. Happy to wait for 48hrs for a good cure 
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I never got this to work… ): It’ll always come loose within the first 100km. I’ve tried letting it cure for a week, cleaning with different agents, lighting sanding it… changing pinions to ensure tighter tolerances… That being said, i’ve never destroyed a motor, the pinion will simply come loose and slides on the motor shaft.
After awhile, I gave up and that’s the reason why the design uses a keyway instead. Glad to know if worked for you though!
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I only used Loctite 648 on my board. It never came loose. You have to clean the pulley and motor shaft good, then put a drop of Loctite on both of them and slide the pulley onto the shaft whilst turning it. Then let it sit for as long as you can wait, but really at least 24 hours. It’s also important how wide the gap between the pulley and the shaft is and what materials they’re made from.
Heres a link to the diagrams Loctite provides:
http://www.schmierstoff-online.de/specs/LOCTITE_648.pdf
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whats the difference between 638 and 648?
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All I could find is that 648 is more heat-resistant.
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I am using the high temperature permatex retaining compound. It is supposed to be made by loctite but it seems to work better by all accounts.
@glyphiks
Supercheap autos has it on the shelf mate.
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Excellent, I’ll add it to the supershit list. Cheers dad.
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There’s also different retaining compounds for different gaps.
I’m surprised at the 2 reports of it-no-work. Wondering if I should make a poll.
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