Chuckles1

Recently finished my first ebike conversion, a 500W Bafang rear hub drive on an inexpensive Motobecane hybrid 3x7 with hydroformed aluminum frame, front lockout shocks, 180mm hydraulic disc brakes. All good so far. I'm used to plopping my other aluminum frame bikes on the work-stand after every ride for a quick once over, and have had no problems just clamping lightly onto the top bar.

I'm loathe to try the same thing on the heavy ebike, especially with a 20Ah triangle battery on there, which I have no intention of removing routinely. While I was putting the ebike together I suspended the bike with bungee chords and old inner tubes rigged to make two slings, one wrapping under stem, the other with an inner tube wrapped around top bar right where it meets seat tube. This worked well, allowing me to work on the rear end with no obstructions. Not easy enough to set up on a daily basis, however, and I'd worry about stress on the frame now that its got a 13 pound battery added to the mix.

Am interested to hear about any creative solutions to elevating the rear end to allow quick safety/maintenance check. I'm not interested in flipping the bike upside down, as with handlebar jacks. I've got a rack and pack on the back or else I'd consider an inner tube sling and overhead pulley just to hoist the rear wheel. There's got to be a solution, but there are precious few places to lift other than that small section of top tube just ahead of the seat tube. There's actually enough top tube there to clamp on my work-stand, but I wonder if the frame could handle 60 lbs. or thereabouts, even close to the weld.

Maybe I'll take a photo later, but here's the bike before the kit was installed.

2old

My bike is closer to 50 pounds especially since the battery is removed each time the bike is ridden. I just use the seatpost. If there's not enough available, temporarily extend it.

Pop N Wood

Pretty bike you have there.

I have an 80's cannondale MTB that weights in at 60# with the ebike kit. I not only clamp it by the top tube on the bike stand, I mount it to my car rack using the same tube. I've driven all over the country this way. I do put the battery in the trunk when transporting it by car, more for theft than to lighten the bike.

It wasn't until I got on this site that I read the hyperbole associated with supporting aluminum frame bikes by the top tube.

All I can say is it must depend on the bike since it isn't an issue with my bike.

cat0020

If you are securing the bike for maintenance or repair, it's better to have the drivetrain at your waist level or slightly higher, you will need a workstand that can secure your bike from the seatpost.

If you just want to suspend the rear wheel so you can work on the drivetrain and don't mind squatting down to do your work, you just need to change your sidestand to a centerstand.


https://www.amazon.com/Lumintrail-Bi...76333269&psc=1

cat0020

If you have your drive motor mounted at the bottom bracket & no room for centerstand, maybe go with this rear axle mount centerstand:

https://www.ebay.com/itm/Durable-Par...cAAOSwZUlgYUMs

andychrist

Chuckles1 said he did a hub conversion. But that Lumintrail double leg kickstand will not work on his bike. Clamp is designed first to mar paint, then to gouge and crush the stays. Once installed it will twist under a load, toppling the bike and do even more damage to the frame. Probably a moot point anyway because it doesn’t look like there is room for the clamp on that Motobecane (thus the side mount kickstand) and even if it could be squeezed in some how, the rear derailleur and brake cables would rub against its sides to ill effect.

My [steel!] frame recumbent bike came quite damaged by the Lumintrail installed by a previous owner. Touched it up best I could, rerouted the cables and reinstalled the kickstand with 3M self adhesive siliconized rubber pads cut to fit over the mounting plates’ inner faces.



Even torqued to the max the clamp barely holds in place and the bike has fallen over repeatedly. Especially since OP does not care to remove the battery pack from his [aluminum!] bike when working on it, I’m afraid any attempt on his part to employ a Lumintrail (or other such type of dual leg kickstand, such as the Pletscher) would be met with disaster.

surveyor6

I put mine on the tail gate of my truck during maintenance.

cat0020

Seems to me you've over tighten the kickstand, which is a common mistake.
Double Kickstand legs are adjustable in length and they are mean to support the bike only; without the rider's weight on the bike.
By "torque to the max" the kickstand will certainly damage your frame, no wonder you've had a disaster with it.

andychrist

No, have only tightened it enough for the included split lock washer to flatten. Who said anything about supporting the rider’s weight? Like I wrote before, it was the previous owner who damaged the frame with it, which I repaired. Also as mentioned, I lined the insides of the plates with siliconized rubber to protect the stays and this has worked perfectly in that regard. Problem is simply that no bike kickstand which relies on its own two plate center mount clamp is guaranteed to support the weight of either a cargo or ebike conversion and in all likelihood will eventually twist out of position. This has been my experience with every brand of double leg stands on numerous bikes over the course of decades.

Again, moot point because OP’s Motobecane cannot accommodate a center mount kickstand anyway, that’s why it comes with the side mounted one.

Incidentally, one advantage prefabbed ebikes generally hold over conversions is an integrated mount with which the kickstand’s built in plate meshes securely, so it will always stay aligned properly and support the extra weight of e-assist.

Hope Chuckles finds an elegant solution.

Chuckles1

I'll probably just clamp it on the top tube just in front of weld at seat tube; all that requires is loosening one Velcro battery strap to make room for the clamp jaws. As for clamping on seat tube, I've never figured out how to do that even with a 20 lb.road bike, without a feat of strength, lifting/balancing/positioning the bike with one hand, clamping it with the other.

Pop N Wood; is your's an aluminum frame? I suspect mine will be ok if I clamp near the weld, as opposed to near the middle of the top tube. The hydroformed top tube is a little scary, as it is quite slender as it approaches the seat tube, but it might even make it stronger.

Quite right those who pointed out that I can't put a motorcycle type stand on it. There's to much going on down there, with internal cables exiting just under and in front of BB shell, and passing underneath.

I've already had it clamped on top tube without the battery, and I will take my chances that clamping aluminum frames being a no-no is hyperbole.

Once you build a kit, you understand the advantages of a purpose built factory ebike. Cable lengths and such, but also an integrated kickstand that lifts rear wheel, and custom fit torque arms and hydraulic brake cutoffs, to name a few.

But the project was fun, and I doubt I could beat the $1,500 I've got in it for a new 700c bike with 48V 20Ah battery. Thanks for all replies.

cat0020

I would not clamp the bike from top tube if aluminum frame.

Seatpost would be better place to clamp, extend the seatpost if needed so there is enough room to clamp,
keep the seat tube as vertical as you can to minimize torsion while working on the bike.

You can lift the bike from the toptube by squatting down, resting the bike near shoulder level and lift the bike by standing up, if you're flexible enough.
Clamp the bike's seatpost with the other hand that's not holding the bike.

Riveting

Pletscher double leg kickstand is my recommendation. It allows full 360° pedaling while on the stand, and while on the stand it's super easy to load/unload panniers or rear trunks.

Pop N Wood

Mine is definitely aluminum. It isn't hydroformed though, too old for that. The round top tube is still pretty thin.

Like you I find it difficult to mount a bike by the seat post.

By the way, the only kick stand I could find that fit my bike was the following

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

My bike was too tall for ones that mount near the bottom bracket, this one is really well made and works perfectly.

I've read this type of kickstand is verboten with aluminum frames as well. Guess I'm not a very good rule follower.

andychrist

I use a similar mount from a Greenfield kickstand. Shim the clamps with 3M siliconized rubber pads and replace the leg with the heavy duty Sataway.



Problem for me was that it couldn’t be used on my ecumbent rear hub conversion, though it should work for an upright where the torque arm can fasten to a seat stay. But does not raise the rear wheel so still no help to Chuckles1

late

You don't want to leave the battery outside all winter.