Gates polychain GT carbon belts

Gates says these are as good as roller chain in some applications. They are stiffer than any belt I’ve ever touched and fantastically expensive. 25$ for a small 300 length belt in m5 pitch.

There was little to no belt torque lag with hard stops and starts.

I have them on there fairly loose, I’m worried they will eat my wheel pulleys.

Someone should see this, not sure who. I’m open to stern warnings if you have seen them chew up regular HTD tooth profiles. I read the Gates disclaimers and cautions.

From Based in Kansas I think.

Sorry no telemetry, I only rode into low 30s (mph).



I’ve had my eyes on these for a ebike project. But as far as I remember gates has their own tooth profile.?

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Calling @b264, the super single might need this


:man_shrugging:, there are compatibility charts out there. Some say ok, Gates says “proper application” shouldn’t.

These are.


Just saw they do have htd belts aswell… Gt carbon has a slightly different profile then htd…It will work tho…

I tried them on 18t pulleys for 5 mins but I was concerned about how tight they were. I loosened drive drain and fit them (what felt like) correctly on 20t.

There are gt3, htd, and the polychain with a white tag on them in above pictures.

Here’s their webpage. They have tension info there if you need it. Poly Chain® Synchronous Belts
I do have plans to reach out to them and ask for cad drawings for the polychain that suppose to have 4x better torque transmission then htd belts. Could ask for pulley drawings for esk8 size and cnc them at the same time I make my pulleys for my ebike…
I think they will slip less then htd belts whem braking

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Evolve has gt3 pulleys.

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Is this a 5MGT belt or an HTD5M?

I’m loving this topic right about now. It’s definitely time for an upgrade.


Why are you ripping so much belts lol. Haven’t ripped one since ages. Lots of single motor builds?

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single motor on unity super single




Yes; single motor builds definitely stress the components to their maximum. Especially when you use the super single configuration with a Unity or something and a huge motor and are fat, and your power limit becomes… well, the belts themselves.

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I’ve seen some ppl use stacked belts, maybe something you could consider. If not, why not just use a chain?

Can’t get/make wheel pulleys wider than 15mm without spending a fortune on HTD5M pulley stock.

Chain would solve this tough, while being dirt cheap.


I would feel more comfortable with a better belt or gears, I just

I don’t know.

Something about a chain spinning that fast makes me feel uneasy, like it’s going to jam up and Superman me off the front into traffic. Probably an irrational fear, but a fear nonetheless.

I’d love to explore the “better belts” route, regardless.

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Well you could just print a cover for the chain drive, no chance of locking up then. Many many motorcycles and bikes are using chains, seems like a proven concept to me lol

You do you, just saying that chains are the best cheapest option here. Like if you get more durable belts they will superman you all the same.