Damn rear derailleurs

Remus

100 W
Joined
Jan 16, 2010
Messages
114
Hi all,

I've been using a Lightning Bolts kit on my bike for about 5 years, have been through 3 rear derailleurs 2 rear cassettes so far.

I'm wondering if there have been advances in a gearing solutions for mid drive power delivery that's affordable and robust ?

Comments and thoughts welcome.

Thank you.
 
Having ridden 30K miles on a 350-500 watt mid-drive with a custom 14-40, 8 speed drivetrain, and 31.6K miles on a 3000 watt DD hub bike, so far, I can say that mid-drives are hard on chains, freehubs, and derailleurs. And if you don't replace chains frequently, you will be wearing out cassettes too. If you are running over 500 watts....fuggedaboutit!
 
There are several threads detailing experiences with IGH systems and mid-drives. the most bullet-proof system seems to be Rohloff, but that one is quite pricey, as is Kindernay. Some success has been had with the Nuvinci/Enviolo CVT systems, as well as the Shimano Alfine. Even some have used Sturmey-Archer hubs.


Few IGH systems, and even few standard derailleur systems were designed for any more torque that the average rider can put out, so adding all that power and trying to pass it through components not specifically designed for it mean that they can break, and even if they don't, they can wear quickly. The IGH systems don't require narrower, potentially weaker chains, and can turn a somewhat less wear-prone larger rear sprocket etc. A drawback is that failures are often difficult and/or expensive compared to common systems.
 
Remus said:
I've been using a Lightning Bolts kit on my bike for about 5 years, have been through 3 rear derailleurs 2 rear cassettes so far.

Chains and cassettes are highly disposable when used with high powered mid drives, but what are you doing to wreck your derailleur?

I'm thinking maybe you need a shift sensor to interrupt power for you.

For robust and affordable drivetrain parts, it doesn't get any better than Microshift Acolyte 8 speed:

https://www.microshift.com/news/introducing-acolyte/
 
MicroSHIFT Acolyte
- I'm done going in half ass, time to go with having good components, at a good value, set up the right way and doing things right and the Acolyte seems to be a solid choice. When I was looking for components for the gearing I want on my ebike, the Mezzo and R8 came up a lot, for 7/8 speed stuff, good value, capacities/wrap I needed for a possible 11-34 rear gears and possible crank switchup. I do not think I will be switching anything up but just installing a cycle computer to measure speed and keeping everything reasonable.


Mid Drive
- Wear and tear on the drive train is an issue with high power setups.
- Shifting gears while mid drive is powered is another big issue, as mentioned.
- Low power setups, components can last a long time. Switch out the chain frequently as mentioned.

I abandoned mid drive long ago, recently I tried to get back into it but it never worked out. I am sure I could tweek things here and there but something will come up, again, and I could be stranded, again. I prefer simplicity and direct drive hub motors fit that bill, but I must admit I love the freewheeling nature of geared hub motors and mid drives. I only do e-brake-low and I honestly do not know if that regens energy back into the battery with cheap generic controllers. When I use e-brake-low, I actually lose watt-hours by noticing less total distance ridden and I ride every day.

For the majority of people, mid drive is not needed and that is the case for me as there is very little steep hills here.
The need is to select the right hub motor with the right power that can go up the hills your riding at the speed you like.
When I first rode the C4k (mid drive, 4000W) and I was stopped on a 20% grade and the mid drive climbed like a mountain goat with 415lbs (380lbs of me + ebike, frame), I have never had that situation come up in any day to day riding being stopped on a 20% grade, for me on a front hub motor 1500-2250W at ~330lbs (total, 280 of me + everything else and I havent weighed components) there is always a run up to any hill, throttle (power) through the hill and if necessary help with pedaling up the hill if the hill is to much. My new hub gearing setup I havent tested on steep hills yet, but hills here are short. The solution for me on a hub would be to go from a Grintech 52V 40A battery with BMS and a 36V battery on a 36V 35A controller, would be to get a new controller and my 36V battery would no longer be used as I'd say its limit is 35A. An upgrade for me on a front hub would be using a 48V 40A controller or a 52V 50A or higher voltage battery with corresponding controller to meet extra wattage and amp needs by the battery.

Here is a good talk about the difference and what you should choose.
https://www.youtube.com/c/GrinTechnologies/videos
Its one of the class room talk type videos, could be "Deep Dive...efficiency" or "Understanding Everything"
but its all good stuff.


Reasonably priced :thumb:
Chalo said:
https://www.microshift.com/news/introducing-acolyte/

Acolyte.png
 
No derailleur or IGH will perform well if you're not controlling power output during shifts, that is a fact. Even a Rohloff shifts like a piece of garbage if you don't cut power.

My solution has been to manually interrupt power during the shift with an additional mini-lever, which uses the front ebrake interrupt. This works great but it requires practice, becomes second nature, like operating a fast clutch on a manual transmission. Much, much better than shift sensor.

Ultimately, even with best practices, buying cassettes, chainrings, and chain can't be avoided with motors like Bafang Ultra. I have a new solution coming which doesn't require any special interrupt tricks, and will tremendously reduce the wear on drivetrain parts, yielding a high power mid-drive with the lowest cost per km of anything on the market.
 
Deafcat said:
No derailleur or IGH will perform well if you're not controlling power output during shifts, that is a fact. Even a Rohloff shifts like a piece of garbage if you don't cut power.
And you'll end up damaging it as well, from personal experience.
 
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