mikefish
100 W
from Sears...LOL :lol:
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Found an awesome torque arm
- Thread starter mikefish
- Start date
dogman dan
1 PW
If you break it, do you get a free new one like they did in the old days.
mikefish
100 W
for the record, its not my torque arm, when i say i found a torque arm, i meant i found this pic on the web! lol
and yes, according to craftsman, they are still replaced if broken for life!
and yes, according to craftsman, they are still replaced if broken for life!
Link
1 MW
I do believe DocBass uses two of those as torque arms. :|
edit: cross-posting the other big torque arm thread so a search will turn up both
"torque arm picture thread" (6 pages)
http://endless-sphere.com/forums/viewtopic.php?f=2&t=26444
Since a search of "torque arm" will turn this thread up, here's a popular one from ebikes.ca ($24 USD + shipping)
"torque arm picture thread" (6 pages)
http://endless-sphere.com/forums/viewtopic.php?f=2&t=26444
Since a search of "torque arm" will turn this thread up, here's a popular one from ebikes.ca ($24 USD + shipping)
Joey
100 W
I like the torque arm from texaselectricbikes.com for use with BMC rear hub motors (~$20 USD + shipping).
Joey
Joey
A recent creative home-made unit, it takes the place of the stock steel insert between the aluminum frame and the steel axle:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=11823
http://endless-sphere.com/forums/viewtopic.php?f=2&t=11823
Another pic from the archives:
chet
100 W
look at e-bikekit.com
Since this is turning into a great torque arm thread, I want to also add my favorite pics of damaged drop-outs...even if the wheel doesn't fall out,...if the axle spins, the wires to the motor will get ripped out at the roots.
John in CR
100 TW
I prefer torque dropouts. I just wish better dual suspension bikes and forks made of steel were available. Hopefully steel bikes will make a comeback as powerful ebikes gain popularity. The one I'm working on now to use with one of my Methods 100V100A controllers will have a thickness of over 1.5" in total for the 2 sides with the extra material using pieces cut from the very hard steel of truck leaf springs. They'll be made to fit the axle tightly, unlike dropouts and torque arms that have play. As an extra over-the-top part of the plan, I will fit hardened steel bolts at the ends of the dropouts to clamp the dropouts on the axle, so even if the nuts came all the way off, my hub motor would still be held securely in place. Pics to come.
FWIW, the vast majority of torque arms are too thin IMO. Many hubmotor axles are made of relatively soft steel, and while the torque arms may not fail, they can cut into the axle allowing it to spin. This happened with my very first hub motor in the first 10ft of my first ride when the AL alloy dropouts snapped. The thin stainless torque arms I made avoided total catastrophe by holding the wheel on, but the axle spun, and changing the wiring harness really sucked. With my homemade steel solution I've yet to have even a loose nut on my 2 bikes with 1/2" thick dropouts on each side.
As regen braking becomes prevalent, new and better fitting torque arm solutions will be required. Even the wrench solution in the OP aren't good enough, because a 10mm wrench has too much play on a 10mm axle.
John
FWIW, the vast majority of torque arms are too thin IMO. Many hubmotor axles are made of relatively soft steel, and while the torque arms may not fail, they can cut into the axle allowing it to spin. This happened with my very first hub motor in the first 10ft of my first ride when the AL alloy dropouts snapped. The thin stainless torque arms I made avoided total catastrophe by holding the wheel on, but the axle spun, and changing the wiring harness really sucked. With my homemade steel solution I've yet to have even a loose nut on my 2 bikes with 1/2" thick dropouts on each side.
As regen braking becomes prevalent, new and better fitting torque arm solutions will be required. Even the wrench solution in the OP aren't good enough, because a 10mm wrench has too much play on a 10mm axle.
John
PeteCress
1 kW
One thing in it's favor: you need to carry that wrench anyhow in case the tube needs tb replaced and that would solve the problem of where to store such a large wrench.
I'd use the other end though to reduce chances of it working loose on bumps.
I'd use the other end though to reduce chances of it working loose on bumps.
SilverSurfer
100 W
I agree about the thickness of torque arms being universally too thin! I bought two of the amped bike versions for my sled, but when I was doing the build thought the surface area of one on each side was insuficient. So I put both on one side doubling the surface area on that side. The wire side of course. Im going to get two more for the freewheel side, then will have 4 total. I mounted the original torque tab washers on the inside so I have those in there too. I did the wire side fully first so I only have a few minutes labor to add two more to the freewheel side. After seeing this though, Im seriously considering the craftsman torque arm for the freewheel side. Its fully hardened, got more than double the standard torque arm surface area, and the length lends itself to better torque leverage! Dont know how a 10mm wrench is gonna help get that 21mm axle nut loose! But what the hey! LOL I love the idea!
John in CR
100 TW
The problem with wrenches is every axle I've seen has play with any size wrench. A smaller wrench ground out to make a tight fit is the way to go. I've done that and heated up the wrench to bend to a bike fitting shape works well, though not attractive. If you could lock a crescent wrench, that could work and be useful later.
Also a boxed in wrench to fit the nuts, and be installed on the right side would be good for a non-regen bike, so if the axle tries to turn, the direction would be for the nut to tighten. There are good arguments made that it's the nuts that hold the axle from turning, as much more more than the dropout/torque arms themselves. From the easily stripped threads on many soft and small hub motors axles I've seen, I'm not relying on the nuts, but experienced guys like Dogman and I believe Justin too swear by them. I do ensure my steel dropouts have very rough surfaces on the nut side using a grinder, so my toothed face nuts really grab hold, and I've yet to get even a loose nut that way.
I believe my new method with the tapped hole for a clamping bolt for the dropout to clamp tightly on the axle is the way to go as pictured and discussed here http://endless-sphere.com/forums/viewtopic.php?f=3&t=15678
Also a boxed in wrench to fit the nuts, and be installed on the right side would be good for a non-regen bike, so if the axle tries to turn, the direction would be for the nut to tighten. There are good arguments made that it's the nuts that hold the axle from turning, as much more more than the dropout/torque arms themselves. From the easily stripped threads on many soft and small hub motors axles I've seen, I'm not relying on the nuts, but experienced guys like Dogman and I believe Justin too swear by them. I do ensure my steel dropouts have very rough surfaces on the nut side using a grinder, so my toothed face nuts really grab hold, and I've yet to get even a loose nut that way.
I believe my new method with the tapped hole for a clamping bolt for the dropout to clamp tightly on the axle is the way to go as pictured and discussed here http://endless-sphere.com/forums/viewtopic.php?f=3&t=15678
PeteCress
1 kW
Assuming they are structurally adequate, these things from Renissance look pretty slick to me.
I have two of them on my 9C setup and intend to use two more on an eZee setup.
In addition to aesthetics, the advantage I perceive is quicker/cleaner wheel removal - since they can be loosened with just a few turns of the Allen key I carry for other purposes.
I have two of them on my 9C setup and intend to use two more on an eZee setup.
In addition to aesthetics, the advantage I perceive is quicker/cleaner wheel removal - since they can be loosened with just a few turns of the Allen key I carry for other purposes.
Attachments
SilverSurfer
100 W
That is one well engineered set up! A bike built for hub motors from scratch should have such a design. Every single point is perfect. Lose the nuts, you cant still go home without a worry! HELL! I WANT! LOL Now to figure how to take that design and make it a bolt on version for everybody. OUCH! Brainiac attack! Wheres those dang asprins!
John in CR said:
SilverSurfer
100 W
Those are nice and thick too. must be the thickest production arms out there. Good set up for FWD.
PeteCress said:
John in CR
100 TW
SilverSurfer said:
Thanks SS, and I've thought about having my machine shop buddies do up a bunch for cheap based on the concept, but a bit thinner, lighter, prettier. The problem is one size can't fit all. Bikes are just too different. For front hubs I think a more standard approach is possible using the same clamping concept, but with what I call torque sleeves. Sorry I couldn't lay my hands on mine for a pic (haven't used them since our move). Picture an L shaped version with the new thick steel dropout tapped and cut for clamping on the axle at the bottom of the L. That is then welded to strong steel straps that wrap around and form clamps to any existing suspension forks. If you consider it permanent just cut off the existing alloy dropouts for essentially identical length and geometry, or you can keep the existing dropouts intact and the new steel dropouts are about an inch lower. Brake caliper mounting holes would be incorporated in the new dropouts, and one size should fit all.
My buddies and I are seriously considering a bunch of frame conversions for integral kits down here. If we do the initial learning process will develop standards for us for such parts, and dropout failure is an unacceptable risk for anything I'm involved with selling. Even though our local market is sufficient, I'm sure we would test out some international sales starting here with forum members after passing samples around to the resident experts for testing and suggested improvements.
If I could track down a manufacturer of quality steel suspension forks, then dropout modification for ebike use is simple. Another possibility is finding raw shocks for small motorcycles, make them ebike motor ready, and sell them along with triple crown headsets designed for bike headtubes. The latter is what I'm doing for my build, but using a complete motorcycle headset including the head tube and first 6" or so of the motorcycle's top and down tubes.
There's a nice opportunity for a cottage industry of better ebike parts, because the junky chinese stuff is inadequate for higher performance, and other than DIY fabrication the other option is paying 6 grand plus for complete bikes, which is clearly ridiculous.
John
John in CR
100 TW
Ah, found them. These are the AL forks from my first hub motored bike. The AL dropouts snapped off after less than 10ft despite very thin stainless torque arms. The shocks were still perfect and new, so I fixed their ass so that could never happen again. I made 2 L's out of 1/4" steel plate, and doubled it up at the axle to cut the dropouts. I welded the L to some steel tubing that I slit open to slip on and fit tightly on the shock body. I used silicon as glue slid them for with wheel attached for perfect alignment until the silicon set.
That was almost 2 yrs ago, and I hadn't yet thought of the clamping bolt, so you'll not those dropouts are for 17mm flats. The reason was that used hubbie had stripped threads, because someone put the wrong thread size nuts on it. My answer was to make new flats, but they had to remain removable to get the motor covers off later. I tapped and threaded the inside of a piece of steel to create a full threadlength nut, and machined the flats onto it. The motor torque would be such that one would loosen, but it wasn't going anywhere because the other side wouldn't screw on any further and any rotational force would try to tighten it. An inch and a half of threaded nut isn't going anywhere.
The only things more to do is add holes for disk brake calipers and put them on a weight loss and shaping program, which would also pretty them up. Right now they're still Frankendrops. 8)
View attachment Torque Sleeves 1.JPG
That was almost 2 yrs ago, and I hadn't yet thought of the clamping bolt, so you'll not those dropouts are for 17mm flats. The reason was that used hubbie had stripped threads, because someone put the wrong thread size nuts on it. My answer was to make new flats, but they had to remain removable to get the motor covers off later. I tapped and threaded the inside of a piece of steel to create a full threadlength nut, and machined the flats onto it. The motor torque would be such that one would loosen, but it wasn't going anywhere because the other side wouldn't screw on any further and any rotational force would try to tighten it. An inch and a half of threaded nut isn't going anywhere.
The only things more to do is add holes for disk brake calipers and put them on a weight loss and shaping program, which would also pretty them up. Right now they're still Frankendrops. 8)
View attachment Torque Sleeves 1.JPG
SilverSurfer
100 W
I am also a machinest and an inventor. I have found mfg.com to be an excelent source of short run parts. You have to be carefull, like eBay or any web based business, there are those who would take advantage of you. The nice thing about mfg.com is you put in your blue prints and specs, and manufacturers from around the globe make bids on your project. You get to look at each bidders profile, accept one you want, or pass on them all. up to you. I have done business there, I had no bad experiences.
Another great choice for already manufactured equipment is Alibaba.com I have also done much business through them, again, no complaints. You put in a request for whatever, and companies from around the globe though mostly Asia make bids on your request. Take or leave, each has a profile.
Besides my degree in machine trades technology, I have an industrial maintenance technician vocational degree, and experience in machine fabrication as well and tool and die experience. Cant lend you my hands on help, but as a mechanical engineer I am quite handy.
Take it easy and good luck~! Great project with a serious need and large client base.
I have an idea for a sight modification to your design. feel free to use it if you think its good idea.
SS
Another great choice for already manufactured equipment is Alibaba.com I have also done much business through them, again, no complaints. You put in a request for whatever, and companies from around the globe though mostly Asia make bids on your request. Take or leave, each has a profile.
Besides my degree in machine trades technology, I have an industrial maintenance technician vocational degree, and experience in machine fabrication as well and tool and die experience. Cant lend you my hands on help, but as a mechanical engineer I am quite handy.
Take it easy and good luck~! Great project with a serious need and large client base.
I have an idea for a sight modification to your design. feel free to use it if you think its good idea.
SS
John in CR
100 TW
SS,
Your pic is too big so I can't see the right side, but I assume both sides are equal. I've been considering adding a clamping to the other side of mine as well. Yours will obviously use less material, so less weight. In fact your way is the route many downhill bikes are going. The only potential advantages I see for a slotted approach are:
1. Easy to mount, ie just slide the axle in the slot and it's held in place while lining things up before clamping
2. Having a slot leaves room for adjustment to align the wheel and/or tighten the chain for a rear motor single single gear chainline.
3. Even if the bolt came loose, there would still be a dropout and the nut would hold it in place as if nothing happened. The other route leaves you absolutely dependent on both bolts always staying tight and in place.
Your pic is too big so I can't see the right side, but I assume both sides are equal. I've been considering adding a clamping to the other side of mine as well. Yours will obviously use less material, so less weight. In fact your way is the route many downhill bikes are going. The only potential advantages I see for a slotted approach are:
1. Easy to mount, ie just slide the axle in the slot and it's held in place while lining things up before clamping
2. Having a slot leaves room for adjustment to align the wheel and/or tighten the chain for a rear motor single single gear chainline.
3. Even if the bolt came loose, there would still be a dropout and the nut would hold it in place as if nothing happened. The other route leaves you absolutely dependent on both bolts always staying tight and in place.
Rassy
1 MW
There's probably other better ways, but when I really want to see the whole picture I just highlight it and copy it, then paste it on a blank page of my word processor (Microsoft Works).
John in CR
100 TW
Paint is my weapon of choice, so I can easily modify, resize, etc the pic.
View attachment hubmotor axle clamp.JPG
View attachment hubmotor axle clamp.JPG
