Cryptic
10 W
LightningRods said:
Having ordered 2, is it easy enough to remove one?
LightningRods mid drive kit
- Thread starter spinningmagnets
- Start date
Having ordered 2, is it easy enough to remove one?
LightningRods
1 MW
Cryptic said:
The only remotely tricky bit is that you need to use the outer barrel or female part of single chainring bolts in order to get the bolts to fit and tighten properly. You still need to use the longer male double chainring bolts. The reason for this is that you are running two chains side by side, something that is not done with a normal chainring setup. Beyond that you just remove the small 32T chainring with it's washer spacers.
For people running a double chainring with front derailleur I want to emphasize again the importance of adjusting your derailleur stops. The derailleur should not be able to push the chain off of either the front or rear chainring if the stops are properly adjusted. If the chain gets stuck between chainrings on shifting that means that there are too many spacer washers for the chain and derailleur you are running. Again, typically bikes with a lot of rear cogs will run tighter spacing on the front chainrings.
skyungjae
10 kW
I think someone on the GNG side actually destroyed their front derailleur when they were running 2kW+ on their set up. They were using a triple chain ring set up like a 32T/44T/44T (outer ring occupied by the motor).
How many tooth chainrings are people using here? If I were limited to one, I'd probably just use a 32 or 34T.
I've heard of someone using a quad ring set up with a 24T mounting to the 5 hole freewheel bolts. I don't know why someone would need all those gearing combinations though... perhaps they were only pushing out 100W. :lol:
How many tooth chainrings are people using here? If I were limited to one, I'd probably just use a 32 or 34T.
I've heard of someone using a quad ring set up with a 24T mounting to the 5 hole freewheel bolts. I don't know why someone would need all those gearing combinations though... perhaps they were only pushing out 100W. :lol:
LightningRods
1 MW
skyungjae said:
Are you riding a 29er? Top speed on a 26 inch with a 32T would be maybe what? 20 mph tops? Oh wait, you're still running 1/2" chain with a 150 rpm cadence. That explains it.
waynebergman
100 kW
Regarding front derailleur adjustment and line up I wonder if it would be a good idea to go with a simple old school friction shifter instead of the index triggers. I have found the width of the front derailleur cage to be wider than I would like, and I think they are designed that way so if the cage is not perfectly centered over the front rings it will not make noise and rub on the chain.
I wonder if a front derailleur cage was jury rigged somehow to be a little narrower it could then be adjusted in with a friction shifter so the front derailleur cage is perfectly centered on the chain and then help keep the chain from falling off.
Just a thought, not sure if this would work or not?
I wonder if a front derailleur cage was jury rigged somehow to be a little narrower it could then be adjusted in with a friction shifter so the front derailleur cage is perfectly centered on the chain and then help keep the chain from falling off.
Just a thought, not sure if this would work or not?
- Joined
- Feb 15, 2013
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in my previous life as a bike mechanic we used to make slight bend adjustments to the front derailleur cage using a small crescent wrench etc to enhance its chain pushing properties at the points of shifting contact..
so yes you could bend the derailleur cage slightly making it narrower to help prevent chain drop.. just do a very small adjustment at a time.. don't over do it.. too much bending will weaken the steel..
so yes you could bend the derailleur cage slightly making it narrower to help prevent chain drop.. just do a very small adjustment at a time.. don't over do it.. too much bending will weaken the steel..
waynebergman said:
has anyone using the kit with high load also used a freewheel in the crank? i'm just wondering as i understand that even w-i can't handle the load for a long time, which is why someone is building me a secondery freewheel behind the crank, so it would take the load of the single bearing.
LightningRods
1 MW
waynebergman said:
I think that friction shifters may be a lot more flexible for custom gears. I want to have heavy duty stainless steel sprockets made for a five speed rear gear set. For electric bikes five speeds is plenty as long as the overall gear spread is wide enough.
LightningRods
1 MW
jdevo2004 said:
Four gears would be plenty. The bikes with more than 10 speeds are trying to compensate for the 100 rpm powerband that humans have. My motors have a 3,200 rpm powerband at 48V. At 96V that increases to 6,400. That's like having an entire gearbox full of speed ranges with human power in just one gear.
Before you start thinking that multiple gears aren't needed remember that having a four speed effectively doubles the power of a motor.
--freeride--
100 W
- Joined
- Jul 5, 2011
- Messages
- 237
5 speed, 6speed 4 speed, no problem
Buy an cheap shimano or sram 7/8 speed cassette, pull it appart and only use the gears u want.(You need a second one or a singlespeed kit for spacers) thats what I allways do. The distance between the gears has to stay as it was befor you did pull it appart. If you end up with 5 gears you take an 8 speed shifter and block 3 gears you don't have with the rear derailleur block or stop screws (you may need longer ones).
Thats an 8 speed which I made a 6 speed and added a 42T on the left, so thats a 7 Speed 13-42 where the most left chainring is missing.
Somtimes it does not shift very good if u leaf gears out, u can then use a grinder to make the shifthelpers on the gears bigger. The cassette above needed some help and is now running very smooth.
I am running a damped 10 speed shimano derailleur with an 8 speed Sram shifter on it. A front chainguide is not needed even on the hardest offroad abuse
P.s. If you trying to bend the front derailleur make it hot befor u bent it. It is hardend if you heat it up once, the steel looses his hardness and is easy to bend. If you don't make it hot it might break.
Buy an cheap shimano or sram 7/8 speed cassette, pull it appart and only use the gears u want.(You need a second one or a singlespeed kit for spacers) thats what I allways do. The distance between the gears has to stay as it was befor you did pull it appart. If you end up with 5 gears you take an 8 speed shifter and block 3 gears you don't have with the rear derailleur block or stop screws (you may need longer ones).
Thats an 8 speed which I made a 6 speed and added a 42T on the left, so thats a 7 Speed 13-42 where the most left chainring is missing.
Somtimes it does not shift very good if u leaf gears out, u can then use a grinder to make the shifthelpers on the gears bigger. The cassette above needed some help and is now running very smooth.
I am running a damped 10 speed shimano derailleur with an 8 speed Sram shifter on it. A front chainguide is not needed even on the hardest offroad abuse
P.s. If you trying to bend the front derailleur make it hot befor u bent it. It is hardend if you heat it up once, the steel looses his hardness and is easy to bend. If you don't make it hot it might break.
--freeride-- said:5 speed, 6speed 4 speed, no problem
Buy an cheap shimano or sram 7/8 speed cassette, pull it appart and only use the gears u want.(You need a second one or a singlespeed kit for spacers) thats what I allways do. The distance between the gears has to stay as it was befor you did pull it appart. If you end up with 5 gears you take an 8 speed shifter and block 3 gears you don't have with the rear derailleur block or stop screws (you may need longer ones).
Thats an 8 speed which I made a 6 speed and added a 42T on the left, so thats a 7 Speed 13-42 where the most left chainring is missing.
Somtimes it does not shift very good if u leaf gears out, u can then use a grinder to make the shifthelpers on the gears bigger. The cassette above needed some help and is now running very smooth.
I am running a damped 10 speed shimano derailleur with an 8 speed Sram shifter on it. A front chainguide is not needed even on the hardest offroad abuse
P.s. If you trying to bend the front derailleur make it hot befor u bent it. It is hardend if you heat it up once, the steel looses his hardness and is easy to bend. If you don't make it hot it might break.
Just curious....why did u put such a large sprocket on the rear?? What is the benefit??
--freeride--
100 W
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- Jul 5, 2011
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- 237
The BBS02 has only one chainring up front, so there is no chance for a small chainring. To get a good reduction and high topspeed I went with the 42T in the back.
I still would like more reduction for steep sections.
I still would like more reduction for steep sections.
LightningRods
1 MW
What I'm going to experiment with is making a five speed that has the widest possible spread of ratios and thickest possible sprockets. I'm going to try having them laser cut and water jetted out of stainless steel. Getting them to shift well is going to be the challenge. It would be great to have the full spread of ratios that we need with five cogs in the back and one chainwheel in the front. With the powerband of an electric motor five speeds total should be plenty.
LightningRods said:
you shouldn't try to make one model that does it all might be over-reaching, the same way even 9 sprockets have several models of several ratios. might be suitable for different types of riders. additionally thick sprockets might present a problem chain standard wise.
personally i don't see myself going back to a cassette, unless the alfine won't be able to withstand anything for a long time, the relieve that i don't clean crap ,and lubricate every other day, not worrying that some nylon bag gets captured up in a rear derailleur bending it from the sheer force of the motor (as it happens once) , not worrying about chain skipping and dropping, not worrying if it gets hit on the side, being bent, is huge plus for me.
hey want a challenge, design a robust 5 gear IGH WITH a motor inside it
skyungjae
10 kW
LightningRods said:
I agree. When riding my GNG set up with the triple chain ring up front, I would rarely ever shift the rear unless I had to climb. It was basically the 32T ring up front when riding from a stop to about 15mph then shifting to the bigger 44T ring to cruise at around 25mph-ish.
Using a custom 5 speed cassette, an old 7 speed deraileur, and a single speed chain might work great.
spinningmagnets
100 TW
Because of the high magnet speed, combined with the very high 33:1 reduction, this kit puts out a tremendous amount of TORQUE, which will be disproportionate compared to what you may be used to when considering "X" amount of watts applied to a small diameter DD hub. As an example, a large diameter DD hub would have more torque than a small-diameter DD hub using the same amount of watts.
I'm not sure about the best way to measure the output torque at the wheel, but I suspect there is no IGH that will survive, and this opinion is coming from someone who really likes IGH's.
If you want an IGH on a mid drive, perhaps consider a 750W BBS02. The LR kit is a chain-breaking beast (if you are not careful).
I'm not sure about the best way to measure the output torque at the wheel, but I suspect there is no IGH that will survive, and this opinion is coming from someone who really likes IGH's.
If you want an IGH on a mid drive, perhaps consider a 750W BBS02. The LR kit is a chain-breaking beast (if you are not careful).
maxwell92036
100 W
- Joined
- Dec 13, 2011
- Messages
- 132
IGH with any system 500 watts and up will probably fail. I am an endurance bikepack racer (no motor assist) and the only IGH held in high regard is the rohlhoff hub. Check out bikepacking.net or mtbr.com for more info and reviews. At least with a cassette system everything is out in the open and easy to fix or replace. For more than 1000 watts I would use a hub motor.
People here seem intent on modding things beyond what they were designed for and then complaining when things go wrong!
People here seem intent on modding things beyond what they were designed for and then complaining when things go wrong!
LightningRods said:
I don't understand why you think "torque sensing wouldn't work because the motor is always pulling the BB away from pedals, sort of a reverse feedback loop that causes diminishing power input" I think if, for example, you have a pedal assist set to add say 50% to your human power the THUN would be sensing only the human power to the left crank and doubling it to approximate the total human power to both cranks and then telling the motor controller to apply that much power to the right motor driven chain ring. The THUN won't know or care what the motor is doing as it's power is going directly to the right chain ring and crank. This will make the bike accelerate or go 1.5 times as fast as with only the human power - BUT it will not eliminate the left crank pedal torque being applied by the human and sensed by the THUN. Thus no reason why it wouldn't work. The human will just be able to go up 1.5 times as steep a climb with the same effort.
Have either of the 2 kits you are building been tested yet?
THANKS
LightningRods
1 MW
I love the idea of an IGH but I'm not even going to try it myself. It's been widely documented that derailleurs handle more power and the cogs are easily replaced when they pack it in. I'm going to try to build a heavy duty derailleur type transmission. If that fails I'm going to look at adapting a lightweight motorcycle transmission running a single run chain line.
No one has had a chance to run my kit with a torque sensor yet. I hope it works because that will be a great option for a lot of people. I would think that it's doubly important to get the reduction right for torque sensing. How can you have torque sensing power assist that runs faster than you are able to pedal? You want full motor power to coincide with max pedal cadence.
It will be fun when we have some hard data back and can stop hypothesizing.
No one has had a chance to run my kit with a torque sensor yet. I hope it works because that will be a great option for a lot of people. I would think that it's doubly important to get the reduction right for torque sensing. How can you have torque sensing power assist that runs faster than you are able to pedal? You want full motor power to coincide with max pedal cadence.
It will be fun when we have some hard data back and can stop hypothesizing.
--freeride--
100 W
- Joined
- Jul 5, 2011
- Messages
- 237
LightningRods said:
The Idea is good, but the cheap 12-15$ shimano and Sram 8 Speed cassettes are made of hardend steel. So i would guess that wider non hardend gears won't be better. Also the shift pefomance already can suck if u take out only one gear on a stock cassette... and it is not that easy to make it shift better again with a grinder...
Then there is the point, does a Bike chain shift well at all on wider gears, I don't think so. You take a non Bike chain, it won't shift at all...
For me the best way to go is cheap high quality 8 Speed stuff and big gears. Take a stock Cassette with a wide spread 11-34 or 13-34 and take away the small gears (11-12-13) start with 14 or 15. the reduction on the 34 is still more than 2:1 and U get a better chain allignment, what helps a lot.
With 14T or 15T there are more teeth attached to the chain and the force to the chain is lower. If u use a big chainwheel up front you can still reach high speeds
62T-14T at 110prm on a 26wheel is 62kph. That is fine for the small block.
For steep slopes you will need a second smaller chainring up front what is ok for me. 39T-34T is nearly 4:1 compared to 62T-14T
If you don't have that already, what about a front spider Adapter that can take 130x5 and 110x5 road Bike chainwheels, the are available with 39-62T(130x5) and 34-54T(110x5).
--freeride-- said:
edit: i keep missing the end quotes,
i should also point out that deeper you travel into making custom bike parts harder, the further its stops being a bike, i mean i could just as easily requested a custom frame from scratch that would support a battery welded into it, but will no longer be a bike, it's sorta like a challenge, explore the boundaries of the toughest STANDARD bike parts you can find on online retailers, because eventually if you end up with a bike made entirely by custom parts, it would be a lot harder to maintain because most of us don't have cnc machining in our back yard (it would fun if we did though)
For steep slopes you will need a second smaller chainring up front what is ok for me. 39T-34T is nearly 4:1 compared to 62T-14T
If you don't have that already, what about a front spider Adapter that can take 130x5 and 110x5 road Bike chainwheels, the are available with 39-62T(130x5) and 34-54T(110x5)
