I keep losing set screws!
- Thread starter Minimichael
- Start date
there are lots of ways to do a jackshaft. and i explain it in the video listed on the prior page, including spacers. i mean set screws are not totally evil. just i've been burned by them, and find it better/more reliable to use spacers. i also find it easier to change jackshaft sprocket with spacers (set screws dig into the jackshaft surface, damaging it, and making it hard to get the existing sprocket and bearings off.)
Yeah and I've been thinking there's a place for each part of the solution. If you're using spacers exclusively, you're overkilling because each washer and length of tube you add is also adding friction between each piece of the puzzle (plus greasing maintenance, loose rattley free-flying pieces of metal, extra weight etc). Now, my same problematic jackshaft happens to be held in the frame not by a tapped end-screw and washer, but by set-screwed collars. And you know what? Those haven't come loose. It's the screws in the gear that can't stay put because they're personally involved in the stress of the gear hanging on for dear life while the chain tries to tear it from the shaft. The poor gear-side screw is clearly the weakest link here, and the drama's all for nothing anyway since a spacer points out that the key is doing all the real work, and the key just needs a wing man — like a collar right next to the gear. That collar's set screw won't (shouldn't) come loose, as it's only job is to hold the collar in place. So maybe a washer between the roller bearing and gear, and a collar to block the key?
One final thought is that my next bike is getting non-original pillow block bearings on either side, for holding the shaft to the chassis. I got-em at the local farmer's big box. Now, do I want to go through all the precise cutting and tapping and perfecting my design into such a custom made fitting? Where each perfect piece of the puzzle needs every other piece to be perfect as well? I do not want that. What if the distance between the pillow blocks needs to be changed? What if the gear I want to swap to has a different width than the previous part? New spacers everywhere? Nah.
Certainly there's uses for each tho. For now I'm going with the locking topper screw solution because I'm too busy being lazy to take the whole thing off just to add a collar to a bike that's already more or less ridable.
One final thought is that my next bike is getting non-original pillow block bearings on either side, for holding the shaft to the chassis. I got-em at the local farmer's big box. Now, do I want to go through all the precise cutting and tapping and perfecting my design into such a custom made fitting? Where each perfect piece of the puzzle needs every other piece to be perfect as well? I do not want that. What if the distance between the pillow blocks needs to be changed? What if the gear I want to swap to has a different width than the previous part? New spacers everywhere? Nah.
Certainly there's uses for each tho. For now I'm going with the locking topper screw solution because I'm too busy being lazy to take the whole thing off just to add a collar to a bike that's already more or less ridable.
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on jackshafts, i use set screws FOR NOTHING. drill/tap the ends of the jackshaft, and use a 5/16-24 bolt at the jackshaft ends. NO collars with set screws. And spacers DO NOT add friction, there's no grease involved! the fact that you even said that means you're missing the whole point of spacers, and do not understand their function. and there's no rattle either if you're using the correct material for spacers. watch the video i posted above. it explains it all. Spacers are more elegant, and make the jackshaft far easier to service, and spacers make the jackshaft WAY more dependable. and you guys understand that center collars with set screws removed are just spacers that are too short! and using collars at jackshaft ends is again, amateur hour. it's just something big to rotate and catch your shoe or ankle upon. ever have your shoe lace eaten up by a jackshaft collar? ha!
i find it adorable that you guys do all these engine mod for performance and dependability, but then cheap out with set screws and collars on the jackshaft...
i find it adorable that you guys do all these engine mod for performance and dependability, but then cheap out with set screws and collars on the jackshaft...
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Again I think it’s a matter of what you’re doing…say @delray out there flat tracking…probably a good place for spacers and jack shaft end bolts stress at every turn etc…some fat bastard like me riding around my neighborhood maybe up and down a gravel road….nah, I’ve Broke more chains than lost set screws….
bet this summer I loose 1000…lmao
bet this summer I loose 1000…lmao
I always drill the jack shafts in a lathe and drill it with a quarter inch hole and then tap at 5/16-24. There’s plenty of meat for that. But if you’re not drilling perfectly centered in a lathe, it’s a bit more challenging…
But you guys are probably right… if you’re just tooling around the neighborhood, set screws are probably fine. But for me collars on the end of the Jackshaft stick out too far and catch my shoes. And Offroad you always lose set screws. So I’m not gonna ever do sets screws for anything again.
also are you saying you're breaking chains? what are you running #35 chain??? i don't have a single bike with anything less than a #41 chain, and frankly, prefer #40 or #420 (if space is an issue.) #35 chain is for kids, not adults.
but I don’t understand why you guys spend all this time and energy on engines, yet your drive train sucks. It seems weird, since it’s all connected. like those street car guys that pour all that money into a hopped up v8, but are running stock rear end...
But you guys are probably right… if you’re just tooling around the neighborhood, set screws are probably fine. But for me collars on the end of the Jackshaft stick out too far and catch my shoes. And Offroad you always lose set screws. So I’m not gonna ever do sets screws for anything again.
also are you saying you're breaking chains? what are you running #35 chain??? i don't have a single bike with anything less than a #41 chain, and frankly, prefer #40 or #420 (if space is an issue.) #35 chain is for kids, not adults.
but I don’t understand why you guys spend all this time and energy on engines, yet your drive train sucks. It seems weird, since it’s all connected. like those street car guys that pour all that money into a hopped up v8, but are running stock rear end...
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Yes 35 unless a torque converter is involved….but that was more of an example more than actual…I’d truly say two each in last four summers….but ive ran out of gas and fouled plugs, lost exhausts, flat tires, lost a seat….broke brake line but that’s not to concerning to me…all in that same period…exhaust was the worst….but, after reading all that, seems I may need a good wrench?
