My Leaf came with such short axles that it was a challenge to mount torque arms on both sides. I ended up going with a 6 speed freewheel and a narrower inside washer to gain enough clearance for the torque arms on that side.
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Leaf / leafmotor / leafbike high efficiency 1500w motor
- Thread starter neptronix
- Start date
yantra yatra
100 W
For some reason I only ended up with one Grin torque arm. I'm not sure if that will be enough. Are two advisable or necessary for 3000w-5000w? I'll see how the Shimano groupset goes anyway. May need to go to 6s in future
The Toecutter
100 kW
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- Feb 8, 2015
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I got away with one arm on the non-pedal-drive/left side by disabling regen at 1500W. With regen, I absolutely needed one on both sides. With just the left arm, the regen caused the axle to rock back and forth in the dropouts and I lost an axle nut as a result.
LInk still doesn't work; same error. Copy and paste the actual page itself to your post, not the link.
If you only use one torque arm, use it on the solid axle side, the one without the wires. If you use it on the wire side, the axle is weaker, and the rocking it might do with only that side locked down will cyclically stress that weaker spot. Some people have had axles of various kinds of motors break there from that.
If you only use one torque arm, use it on the solid axle side, the one without the wires. If you use it on the wire side, the axle is weaker, and the rocking it might do with only that side locked down will cyclically stress that weaker spot. Some people have had axles of various kinds of motors break there from that.
yantra yatra
100 W
Dunno how to get that Ali link to work but for anyone looking for a groupset I got the one called
SHIMANO Tourney 7 Speed Groupset include M315 Shifter TY300 Rear Derailleur HG200 TZ500 Cassette Sprocket 28T 34T HG71 Chain
It sounds like this may not work after all though with two torque arms (I’d like to use regen) so may have to look again for a 6s or 5s option.
SHIMANO Tourney 7 Speed Groupset include M315 Shifter TY300 Rear Derailleur HG200 TZ500 Cassette Sprocket 28T 34T HG71 Chain
It sounds like this may not work after all though with two torque arms (I’d like to use regen) so may have to look again for a 6s or 5s option.
Even the links google finds for that description give the same error.
Searching with that phrase direclty on aliexpress finds quite a few things, no idea which one is the one you're looking at.
If you copy the actual information from the page, picture, etc, and paste it into your post we could see it and tell you what it is.
Searching with that phrase direclty on aliexpress finds quite a few things, no idea which one is the one you're looking at.
If you copy the actual information from the page, picture, etc, and paste it into your post we could see it and tell you what it is.
yantra yatra
100 W
SHIMANO Tourney 7 Speed Groupset
Groupset include 4 original (no box) parts：
1.SL-M315-7R
2.RD-TY300-SGS
3.MF-TZ500-7 / CS-HG200-7
4.CN-HG71
MF-TZ500-7
SHIMANO TOURNEY TZ - Multiple Freewheel - HYPERGLIDE - 3x7-speed
--Lightweight construction
--Easy assembly feature
--Combination 14-16-18-20-22-24-28T - 14-16-18-20-22-24-34T
If this doesn’t work will find a 5 or 6s
Groupset include 4 original (no box) parts：
1.SL-M315-7R
2.RD-TY300-SGS
3.MF-TZ500-7 / CS-HG200-7
4.CN-HG71
MF-TZ500-7
SHIMANO TOURNEY TZ - Multiple Freewheel - HYPERGLIDE - 3x7-speed
--Lightweight construction
--Easy assembly feature
--Combination 14-16-18-20-22-24-28T - 14-16-18-20-22-24-34T
If this doesn’t work will find a 5 or 6s
Ok, that looks like a "standard" thread-on freewheel, that should fit any thread-on sidecover or regular bike hub.
I don't see info on it's width, but if it's like most 7-speeds, it'll be somewhere around 32-35mm. As long as oyu have that much clearance from the side cover (plus the gap between the lowest gear and the cover) out to your dropout's inboard face, plus the width of the chain past each sprocket when it's riding on the outer and inner ones, it should fit.
(assuming no spacer washers, the distance from the sidecover to the axle shoulder that would rest against hte dropout is equivalent to the above distance)
Also, while it could be "real", I don't know that it will actually be Shimano, just as likely to be a clone of whatever level of quality / materials. (a common problem on many websites, not just Ali*). Some of the stuff I've gotten there was alright even when it obviously wasnt' the real thing, and some of it was useless garbage.
I don't see info on it's width, but if it's like most 7-speeds, it'll be somewhere around 32-35mm. As long as oyu have that much clearance from the side cover (plus the gap between the lowest gear and the cover) out to your dropout's inboard face, plus the width of the chain past each sprocket when it's riding on the outer and inner ones, it should fit.
(assuming no spacer washers, the distance from the sidecover to the axle shoulder that would rest against hte dropout is equivalent to the above distance)
Also, while it could be "real", I don't know that it will actually be Shimano, just as likely to be a clone of whatever level of quality / materials. (a common problem on many websites, not just Ali*). Some of the stuff I've gotten there was alright even when it obviously wasnt' the real thing, and some of it was useless garbage.
yantra yatra
100 W
Thanks for the good info! Hopefully this can be useful to others looking for compatible parts.
I have one Grin V7, to get another with shipping is extraordinarily expensive so will prob get a cheaper one, like this Suringmax one, or a generic cheap one. Arc also make a nice one mid range price.
Suringmax also make a 1500w 135mm direct drive. I reckon it would make a good backup bike motor, would be interested to see its performance with statorade
I have one Grin V7, to get another with shipping is extraordinarily expensive so will prob get a cheaper one, like this Suringmax one, or a generic cheap one. Arc also make a nice one mid range price.
Suringmax also make a 1500w 135mm direct drive. I reckon it would make a good backup bike motor, would be interested to see its performance with statorade
It's never a good idea to cheap out on torque arms.
Remember that pretty much all the clones of grin's torque arms (such as the one you show) are almost certainly much less precisely made, so they don't perfectly fit the axle, and allow it to move. So...they don't really do the job they're there for.
If you have some scrap metal (steel) of appropriate thickness (thicker better for spreading load over more axle flat surface area) and a drill and a file and a lot of patience, you can create your own perfectly fitting TA that is better than that, by drilling a hole in the metal then filing that outward until you can *just barely* fit it onto the axle and there is no gap on either axle flat.
There are many ways to make TAs, you can look at many of them in The Torque Arm Picture Thread.
If you have some scrap metal (steel) of appropriate thickness (thicker better for spreading load over more axle flat surface area) and a drill and a file and a lot of patience, you can create your own perfectly fitting TA that is better than that, by drilling a hole in the metal then filing that outward until you can *just barely* fit it onto the axle and there is no gap on either axle flat.
There are many ways to make TAs, you can look at many of them in The Torque Arm Picture Thread.
ZeroEm
1 MW
Have mentioned this before, have two torque arms on my leaf. Have them pulling in different directions to take out the slack. Main reason is regen, it was backing off my nuts. Max power used on my trike is 2700w and one of Grin's torque arms works. The other torque are is to keep regen from turning my axel the opposite direction. Here is were we get back to clamping torque arms. But one of Grins arms will hold the leaf if there is no movement or do not use regen and rock the axel.
Chalo
100 TW
[...]
Yep. There is no benefit to regen that's worth breaking your bike, which is why I'll never use it, nor implement it for someone else. Brakes are much better brakes; more battery is much better than recovering trifling amounts of juice by abusing your machine.
If sellers of reasonably priced, reasonably good quality hub motors start using direct mounted torque arms that work in both directions, I'll consider trying regen. But not until.
The Toecutter
100 kW
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- Feb 8, 2015
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- 1,490
Light regen(< 20 Nm) with torque arms on both sides seems to be zero risk from my experience, and is very useful. Worth having, IMO.
Grin clamping torque arms take the torque arm fit from millimeters worth of looseness & some damage on the bike at >4000w to 0-1mm of looseness, and i don't have long term results but i bet there would be little to no damage from both heavy regen and forward power with a pair of those in a high power hub motor.
I would completely trust them for the kind of no mechanical rear brake setup i had on my leaf 1.5kw. ( 1000-1500w of regen, and used much more often than the front brake to maximize regeneration )
I would completely trust them for the kind of no mechanical rear brake setup i had on my leaf 1.5kw. ( 1000-1500w of regen, and used much more often than the front brake to maximize regeneration )
Chalo
100 TW
Why useful? Why worth having? There's a lot less to maintain, a lot less to go wrong, and better braking if you use, y'know, brakes. And more power and range and battery lifespan if you kick up the battery capacity by the amount of regen energy you reasonably expect to recover.
The Toecutter
100 kW
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- Feb 8, 2015
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I get a 10% or so increase in range, save wear and tear on brake pads, and have a "last resort" brake if my mechanical brakes all fail at once.
Keep in mind that any looseness, over time, equates to rocking of the axle and wear on the contact surfaces of arm, axle, dropout, etc. If the axle and arm are identical hardness, ductility, etc., then the damage will be slower, but if one of them is harder than the other, the softer one will get chewed up.
Anything that clamps down on a larger surface area of the axle flat will disallow this rocking.
If only one side's axle is secured, the rest of the motor core / axle will still rock back and forth, twisting the axle up to the secured point, and can eventually shear thru the axle itself once it has stressed the metal beyond it's limits.
That can happen even if *both* axles are secured if the forces on the axle are great enough, such as with some of the motorcycle-class builds where a lower power motor is used at way higher power levels than it was designed for. (I have an example of that, sent to me after this happened, in a QS205 run at tens of kW vs the three or so it was meant for).
What actually happens on any specific setup depends on the materials and forces in that setup, and the time involved. The longer it's used, the more likely a failure becomes, once material limits are exceeded.
Chalo
100 TW
That 10% comes with drawbacks. 10% more battery gives you the same extra range, but with performance and longevity benefits.
Brakes are a given. Using your motor like a sneaker dragging on the tire isn't a substitute. Maintaining brake pads' "wear and tear" periodically is much less overhead than constantly monitoring your motor axle for signs of looseness, and that's in the best case where you don't spin the axle through inattention.
Causing a catastrophic failure by using regen is orders of magnitude more likely than all your real brakes failing at once.
The Toecutter
100 kW
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- Feb 8, 2015
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- 1,490
My builds are limited in the amount of battery I can fit, so every bit of range helps.
I use regen for 90% of my braking. It's light braking that allows me to stop gently. Heavier regen would actually not be to my liking. My mechanical brakes are for when light regen isn't enough force to stop for the circumstances. I have hydraulic front brakes on my KMX and a rear Avid BB7 mechanical cable pull brake as well(mostly serving as a parking brake). The mountainbike has twin Avid BB7s. The Milan SL has twin Sturmey Archer drum brakes up front, and cannot fit a disc in the rear. All three have light regen in the rear wheel enabled by the hub motor. The quad I plan to build will probably end up with light regen on the twin hub motors that will be up front, no regen from the middrive that will power the rear wheels through the differential, and hydraulic disc brakes on all 4 wheels.
Ever since the first time an axle has come loose on my KMX back in 2021, an axle has never come loose again over tens of thousands of miles. I learned my lesson. Even when my mountainbike's rear caliper moved slightly and caused a bolt to scratch my motor case, the axle didn't move and was still flush with the dropouts on both sides, but regen was the first thing I suspected as the culprit.
You're right that the axle is much more likely to twist loose from regen than all brakes are to fail. But I still like the redundancy. I check each bike once a month. Nothing has gone wrong thus far. The laughably underpowered mountainbike scares me the most out of any of them.
Plus, in a SHTF grid-down scenario, regen could allow you to recharge the bike with human power. When my Satiator charger broke in 2022(my fault for charging it outside in the rain probably over a hundred times, I bought another), I was able to ride my coroplast velomobile over long distances purely pedal powered, and gradually recover electricity to use for later when I needed the bike to visit a job site. That saved me lots of problems with my employer, because without that motor working when I needed it to I'd have been screwed. I love the versatility of regen. Unless I do a dedicated RWD middrive build of a trike or quad at a later date, all my builds will have it.
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I'm the same camp as the toecutter, i never have enough battery for the long rides i want to do.
I also have 6-12% graded mountains to go up and down for miles at a time. This is a situation where regenerative braking is actually necessary; a pair of 203mm rotors isn't enough, the heat shedding capacity is inadequate.
I know of multiple bicyclists from a friend of a friend who have died descending canyons out here because they either wadded up a disc rotor from heat or had a tire blowout if they were using vbrakes, in each case they were suddenly thrown off the bike, and sometimes into the canyon.
I never have to stop and pull to the road because my regenerative brake is fading from heat. 1500w regen is nothing to the leaf 1.5kw, heatwise. The brake response is predictable down these long grades, which is important to me.
Cars also have problems in these areas. I notice some minor brake fade driving down them in my car, and my car has an above average brake power to weight ratio.
This is why i still use direct drive motors in my mountainous area. They have to be oversized and geared down with smaller wheels, but if you do it right, they can repeatedly handle both the climbing and descending part of mountainous riding.
I did 4kw peak on the leafmotor with 1.5kw regen with two very old generation ebikes.ca torque arm plates plus some custom hardware to get no more than 1mm of motion across the assembly, and this worked great; there was only minimal pitting in the bike's dropouts after experimenting with that and 6kw power levels, the dropouts didn't 'change shape'.
I would trust a pair of grin's newer torquearms for that duty, i'm more concerned with the strength of the chainstays on the bike instead, since they are now bearing a lot of the torque load. There is no detectable motion in the motor with a pair of them, and the new bike i've installed and uninstalled them many times on them, and ran 4kw/1kw regen on them, has no pitting other than what i created by hitting the axle with a mallet to get it *really* into the dropout.
I also have 6-12% graded mountains to go up and down for miles at a time. This is a situation where regenerative braking is actually necessary; a pair of 203mm rotors isn't enough, the heat shedding capacity is inadequate.
I know of multiple bicyclists from a friend of a friend who have died descending canyons out here because they either wadded up a disc rotor from heat or had a tire blowout if they were using vbrakes, in each case they were suddenly thrown off the bike, and sometimes into the canyon.
I never have to stop and pull to the road because my regenerative brake is fading from heat. 1500w regen is nothing to the leaf 1.5kw, heatwise. The brake response is predictable down these long grades, which is important to me.
Cars also have problems in these areas. I notice some minor brake fade driving down them in my car, and my car has an above average brake power to weight ratio.
This is why i still use direct drive motors in my mountainous area. They have to be oversized and geared down with smaller wheels, but if you do it right, they can repeatedly handle both the climbing and descending part of mountainous riding.
I did 4kw peak on the leafmotor with 1.5kw regen with two very old generation ebikes.ca torque arm plates plus some custom hardware to get no more than 1mm of motion across the assembly, and this worked great; there was only minimal pitting in the bike's dropouts after experimenting with that and 6kw power levels, the dropouts didn't 'change shape'.
I would trust a pair of grin's newer torquearms for that duty, i'm more concerned with the strength of the chainstays on the bike instead, since they are now bearing a lot of the torque load. There is no detectable motion in the motor with a pair of them, and the new bike i've installed and uninstalled them many times on them, and ran 4kw/1kw regen on them, has no pitting other than what i created by hitting the axle with a mallet to get it *really* into the dropout.
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ZeroEm
1 MW
You will find Regen useful or not. It seems more useful if you are a recumbent or semi-recumbent user. I run variable regen and use it for 95% of my breaking. Still have the original brake pads on my Disc brakes but only get back around 7%. That is sill 1-3 miles per ride. Do need to have the motor locked down both ways, no rocking.
scianiac
10 kW
- Joined
- Oct 24, 2018
- Messages
- 668
I think in the context of a any moderately sized or large hub motor I want it clamped down real solidly regardless if I use regen or not (I do for 95% of my braking). But like I just threw whatever torque on there and eh it's good enough if I don't use regen doesn't sound great to me considering it's not that hard to make sturdy ones. The axle nuts on my Leaf bike are decorative there is so much clamping force and area on that axle.
Clamps FTW in my experience. I have tried everything from slots on my original Stealth that resulted in the rear wheel falling out while on regen to all of grins variants (except the latest clamping one's ironically), a bunch of randoms from ebay, and nothing works for long term decent regen use apart from clamps.
If you look back through the Stealth owners thread (around 2016 from memory) you will see I designed replacement clamping torque arms to solve this problem for myself (while running the Leaf motor @ 8KW) and a bunch of others with stock setups. I had a small run of around 100 manufactured and they all sold really quick! AFAIK they are all still going strong as I've not had a single complaint.
In the case of my current fleet of recumbent's I similarly designed custom machined clamping torque arms and it's been well worth it as they've held up to a collective usage of over 35000km's without issue putting up with regen averaging around 1kw and peaks of over 3kw.
And as far as it being worth it, like others have already said, I would say it absolutely is in a hilly area. I average 6-9% regen, which on my typical 40-60km daily rides is an extra 2.4-5.4km. In addition, some of my rear heavy bikes can struggle with rear brake strength at times. Having the regen really helps solve this and gives a huge boost to rear braking confidence.
Cheers
If you look back through the Stealth owners thread (around 2016 from memory) you will see I designed replacement clamping torque arms to solve this problem for myself (while running the Leaf motor @ 8KW) and a bunch of others with stock setups. I had a small run of around 100 manufactured and they all sold really quick! AFAIK they are all still going strong as I've not had a single complaint.
In the case of my current fleet of recumbent's I similarly designed custom machined clamping torque arms and it's been well worth it as they've held up to a collective usage of over 35000km's without issue putting up with regen averaging around 1kw and peaks of over 3kw.
And as far as it being worth it, like others have already said, I would say it absolutely is in a hilly area. I average 6-9% regen, which on my typical 40-60km daily rides is an extra 2.4-5.4km. In addition, some of my rear heavy bikes can struggle with rear brake strength at times. Having the regen really helps solve this and gives a huge boost to rear braking confidence.
Cheers
