Originally Posted by
noglider
Seriously? That's weird. Why make the belt tight? If it is to save the life of the belt, F...skip that!
I guess the theory is to keep all the teeth in snug contact with all the cogs on the pulleys.
Originally Posted by
noglider
Have you tried an Enviolo? They replaced all the 3-speed hubs (or almost?) on the Citi Bike fleet here in NYC with Enviolo. I like the micro-adjustability, but I think I notice the added inefficiency. And they're extra heavy. I believe the company chose this hub because of the reliability and durability. These bikes are used hard and abused. Apparently, they're very tough hubs. Here, they use chains, not belts. The chains are sometimes rusty and stiff, but they may prefer them because belts might be more vulnerable to vandalism. Or maybe it's because chains (and their sprockets) are so much cheaper.
I haven't had the pleasure of using an Enviolo CVT hub, though I'd like to. I just bought a membership at the Art Institute in Chicago, so I'll keep an eye out next time I go down there.
It sounds like not only are the gearhubs heavy, but also the front brake hub. Not to mention chain guard, wheels, tires and all the anti-vandalism stuff. As you say, it adds up to a nearly 50 lb. bike that lacks a motor.
Originally Posted by
Darth Lefty
Belts normally run tight. The tension needed is about the weight of the bicycle. Gates has an app that uses your smart phone's microphone to measure the frequency when you pluck it.
That was my point though: that level of tension is NOT needed, but someone at Gates thinks it is. Maybe for a strong, heavy rider, really standing up and mashing to climb a steep hill, it would skip cogs and that caused them to recommend the high tension?
I tried the app and its frequency measurement of when the belt is plucked. It's pretty far from precise. They would have been better off telling us about the proper deflection amount when the belt is pressed between pulleys.
If you try one some time and you're able to resist loosening it up when you see the draggy effect of that tautness, I'll be surprised.
