Torque bars for BL-36 front hub

Wow, sounds like an eventful ride.

You can try these people for a torque arm:

http://ampedbikes.com/buynow.html

I've heard good things about them. They seem a little pricey at $25, but it sounds like you need *something* ..and soon. It may sound crazy, and may look dumb, but could you attach a wrench to the square part and then use those screw-on hose clamps to hold it in place till you get something more permanent? Along these lines, check with your local bike shop to see if they have this size wrench in a very thin style. That may make a much lower cost torque arm...

G'luck... !

Are your forks aluminum or steel?

Aluminum forks can be a problem because they typically have a ridge around the dropout that is meant to partially capture the axle of a normal bike wheel so that even if the axle nuts get loose, it won't fall out. The electric hubs have larger axles and more importantly, larger axle washers that don't sit down inside these ridges. If the washer is sitting on top of the ridge and the bolt is tightened, it will tend to widen the dropout as it tries to seat down into the ridges, and because the ridges are tapered toward the bottom, push the wheel out the bottom. I suspect that this is a contributing cause to many of the aluminum fork failures that have occured with hub motors. If your dropouts are aluminum and they've already been bent, I would not remount the motor to this fork. Once bent, cast aluminum is prone to crack and break without any warning. The wheel can fall off your bike. I wouldn't use it even with a torque arm. Go buy a steel fork and start over. It's a lot cheaper and less painful than dental work and medical bills you might end up with from losing a front wheel.

If you fork is steel, then you may still be able to salvage it with a torque arm, but you need to come up with a tapered washer or something to keep that axle from being squeezed out of the fork when you tighten the bolts. I've never seen a steel fork with a tapered dropout like what you seem to be describing, so I'm guessing you must have aluminum forks.

Bummer dude. The exact same thing happened to me except for the cop. Brace yourself, you're in for an adventure. What has happened has little to do with a torque arm and much to do with the fit of the washers on your forks. Many many many forks come with a little bit of a cup shape to them that fits perfect with the bolts, or the quick releases on the original wheel. But when we put a motor on, with the oversise axle so the wires can fit, We get an oversize washer with it. Some bikes can just have a few high spots on the dropout filed off, others may need a big inner diameter, but small outer diameter washer used to fill a sort of a cup in the dropout. A split lockwasher is ususally good for those cases.

In any case, the washers on the hub need to fit perfectly and flatly to work. If they span some empty space, soon,the washer will bend a bit,and now the nut is loose enough to let the axle spin. the flats on the axle can spread the forks easy when it tries to spin. So that fixes the spin problem, though a torque arm is a good idea. I have 1400 miles now with no torque arm, but a good fit on the washers and nuts. I have overtourqed an axles stripping the threads too, so not too too much tighten either.

Now the bummer part. you will very likely need to take your motor apart, to rewire it. If you have cut the wires in the axle, you can just put new connectors on the inside, and have a shorter wire outside. It worked for me. There is a real good post by Link on the Endless Sphere on how to crack a motor. I'm ignorant how to insert a link, but maybe Link can help you out if you can't find it.

And lastly, if you are lucky, you haven't blown your controller. Mine did, and since it was my fault, no warranty. Sometimes cutting the wires blows the controller and sometimes not. If your bike was easy-ish to peadle home, you are likely to be ok.

Good luck, and welcome to the world of ev's Murphy seems to like em.

endless sphere forum, ebike technical section, Disasembly of abused BD36. It should be on page one, I posted to kick it back to the top. I gotta learn to post a link someday.

I don't really understand the wrench problem. Do you have it strapped in to the fork with a hose clamp? You may try a captive 10mm wrench (full circle) to grip it all the way around.

If the forks are to the point where the wheel falls out, you may want to just replace the forks. Your bike looks to be the perfect ebike beast, so I don't think I'd throw it away. Your local bike shop may be able to fix you up with some used forks from people upgrading or whatever, or even new, low end forks are only like $40. If you are handy you can probably find a junk bike and extract the forks -- free. Here's a link to cheap, strong steel forks:

http://www.nashbar.com/profile.cfm?category=&subcategory=&brand=&sku=13284&storetype=&estoreid=&pagename=Show%20All%20Products

(Dogman: to do that maneuver, simply copy the link from another window and paste it into the reply window...easy!)

When you replace the forks make sure you start with a torque arm or wrench equivalent. As far as a new bike goes, that is also an option. I do not know what is "best" cuz I'm just starting out myself. I have a used Torker Metro/BL-36 (400W)

http://www.torkerusa.com/05TorkerCatalog.pdf

and have not applied full power yet (the previous owner ran 36V 8ah for 2 years without problem). I have not seen any fork issues yet, but will *start out* with a torque arm of some kind when I get the 48V 16ah battery from ping...

G'luck!

I'm wondering if your axle was seated fully down into the dropouts. I had to file my dropouts quite a bit to get the larger axle on the hub motor to fit into the dropout all the way. Prior to filing, it would only go about half way to the bottom (top) of the dropout slot. It needs to be seated completely into the dropout slot with a tight fit on the flat sides of the axle in order to work.

I'm running two different bikes as daily commuters with 36v WE hubs and no torque arms. Both have sturdy steel forks, filed carefully so that the flats of the hub motor axle fit tightly and completely into the dropouts. So far, I've not had any problems with the axles or the nuts working loose, but I've only been running them for about 2 months. I check the axle nuts every weekend. I personally wouldn't run more than 36v without a torque arm.

You ever get into a project and reach a point where a little voice in your head say's "this is not going to end well"? I think that is where you are at. I agree with the suggestions that your best course of action is to take the front wheel to a local shop and buy a good used, or new, front fork setup. By taking the wheel you can be certain that the prospective forks fit. In addition, I would add a torque arm for insurance. I just bought the arm from ampedbikes and am pleased. The arm is made of 3/16" stainless and is professionally laser cut and hugs my 10mm axle perfectly. I balked at the price, but after screwing around with a few homemade attempts, I went for it. I should have purchased this arm from the getgo. I'm only running 36v but after looking at the process to repair a motor with 'torn' wiring, I decided to buy some 'cheap' protection. $25 to protect $400 or more sounds reasonable. Tony

In my opinion your dropouts have a little bit of cup built into them as is found on many of the higher priced bikes that use quick release hubs. This small, but invisible air space under the washer can't be seen from the outside and causes the force on the nut to make the dropout spread, and usually the wheel will slide out of the dropout as the nut is tightend. This is exactly what happend to me when I cut the wires and blew a controller on my first test ride.

Different forks will help, or using a small washer, like a lockwasher, or a washer from the original wheels drilled out to fit the new axle size. New or used forks can be had at most bike shops. A lot of folks buy a suspension fork and then the old fork is laying around in the shop. The ones off cheap bikes seem to have the beefiest dropouts, but if you have a good bike, the headset may be the wrong size. the walbikes use the 1" mostly.

I'm having a lot of luck lately buying vintage, sold for $400 new, bikes for 10 bucks at the flea and garage sales. Broken bikes sell for nothing, but have hundreds in parts on em that are good as new. I now have allmost everthing I could ever need in the pile of bikes and my cheap mongoose ebike is sporting parts that are worth twice it's original cost. Apmpedbikes sells a pretty nice tourque arm, if he hasn't had a sellout on em.

Cool, if nothing else, the washers will lay flat on that. I sometimes wonder if the main contribution of a torqe arm isn't providing a better surface for the bolts and washers anyway. If you can find a 26" fork that is better at a garage sale on a broken bike go for it. Something like a BMX bike has is usually the strongest. I'm doing very well, accumulating all the parts I'll ever need at 10 bucks per bike.

These Type P Headless Drill Jig Bushings make great little adapters under the included nuts, so I don't even use the crap washers included. My fork has the "Lawyer Lips"; the feature many of you mentioned, which prevents the hub from dropping out of the fork should the nuts loosen.

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1767627&PMT4NO=51516774

I found this thread with Google: "Wilderness EV axle" I think...

I will contact my friend at Central Armature Works in Washington, DC for advice on torque arms including the one mentioned here in 3/16 inch stainless, or possible a whole new axle that can be pressed in through the bearings.

I gave my hub 45 VDC from an ultracapacitor source at about 1/1000 ohm ESR (Effective Series Resistance) two days ago, and again last night. Two days ago it went from stopped to full speed in probably one revolution. Last night, the axle moved and cut the wires. I've seen the problem before and trashed a whole hub at the Armature Works learning what's inside, and how it comes out.

This is definitely a weak point in the design, but then, forks do vary, so when the maker gets "universal fit" to their advantage, the user gets "sloppy fit that won't hold tight" to their disadvantage. Such is The Bicycle Universe.

Those bushings are 3/4 OD, 15/32 ID, and are 5/16 in length, leaving the nuts fully engaged and flush with axle ends. A set screw on each face of the axle in each bushing (4 setscrews) and a brazed extension on the bushing might make a nice torque arm. The bushings are hardened, I think, and would have to be tempered before threading for the set screw. Brazing might temper them nicely. With 5/16 in length, a 1/4-20 set screw would be a bit large. #12 set screws would fit nicely, and at 24 tpi (threads per inch) with 1/4+ inch of thickness available, would have 6 threads engaged. Recommended practice is minimum 3 threads engaged. Hm. Forks vary, so what kind of extension or peg would be best? I don't know.

Metric equivalent would be M5x0.8 set screw with 8 threads engaged.

Set screws would bear on the flats and would not interfere with hub removal. Just make it take a bit more time.

Here is a source for a torque arm:

http://www.bernsonev.com/phoenix-torque-xtqarm-p-1031.html

Purchased one several months ago and it is working just fine. The clamp several inches up from the dropouts help spread the forces away from the dropouts.

Russ