Q128h 36v from bms battery

[Mattjenkins1990]

Will this motor work with the 48v 09 bottle battery with built in sinewave ?

Many Thanks,

Matt.

 

[Deleted member 4366]

Yes. It's made for it. 48v makes it run 33% faster and gives 33% more power. The 36v 201 rpm then becomes 48v 266 rpm, which means good power up to about 18 mph and assistance all the way to about 22 mph with a full battery and 26" wheels.

 

[Marc Webster]

Yes. It's made for it. 48v makes it run 33% faster and gives 33% more power. The 36v 201 rpm then becomes 48v 266 rpm, which means good power up to about 18 mph and assistance all the way to about 22 mph with a full battery and 26" wheels.

D8veh,

I just posted a similar question in an older Q128 post. Instead of the 09 and 20 amp listed above, can I get away with the 36V 201 rpm Q128C on a 700c wheel with the 48V shark pack and integrated 18amp controller? I see others in the older thread here doing it, but the general consensus on ES was 18amp was too light. Id prefer the shark pack over the 09 due to size and weight.

 

[Deleted member 4366]

That should be OK. I've not tried the Q128C, but those that have seem to like it. One thing about the shark packs is that the base is wide and flat, so doesn't get as much support as the 09, which has a rounder base. IIRC, someone makes a base adapter so that it can be fitted to round frames, or you can make your own out of GRP or something similar. Not a problem if your frame is flat at the bottle mount.

 

[Marc Webster]

Hello D8veh,

Thanks for the Reply. I was unaware of the issue with the round tubes and the shark packs. I did a search on an adapter and found this: https://mountskidmore.com.au/
This should do the trick nicely.

So in your opinion the integrated 18amp controller in the Shark pack will be sufficient?

Is the 09 pack that much better of a choice that I should worry less about size and just go with it instead? My other option is a much nicer battery from Em3Ev but going that route forces me to use an external controller and I do want a much cleaner look that the shark pack provides with its simpler wiring and such.

Best regards,

Marc

 

[Deleted member 4366]

That's not the right adapter. the correct one has a curved side to match the frame and a flat side to match the battery mount. You can make one by wrapping your frame \nd the battery mount in cling film. Screw it on, then shove loads of fibreglass between them. let it cure, then file/grind it to a neater shape. Something like this, where I had to make an adapter to lift one end of the battery:

 

[Marc Webster]

That's not the right adapter. the correct one has a curved side to match the frame and a flat side to match the battery mount. You can make one by wrapping your frame \nd the battery mount in cling film. Screw it on, then shove loads of fibreglass between them. let it cure, then file/grind it to a neater shape. Something like this, where I had to make an adapter to lift one end of the battery:

Hello D8veh,

Thanks for the info on the issues with the flat base on the Shark type battery pack. After seeing your pics, it gave me another idea. I have a product I designed and sell to mount gopro cameras to aircraft struts. Its also designed to mount to tubing as well and I use it on my Hanglider. Anyhow, I can use the mount body to help secure the flat base of the battery cradle to a tube. I will just mount the cradle directly to the body where the ball mount is normally attached.

Here is a link to my website if you want to have a look at some cool videos of the mount in action with various bush pilots as well as others.

www.cloudbaseengineering.com

Below is a pic of how its mounted to tubing. Tube range is 1" to 3" in Diameter.

 

[Deleted member 4366]

That might work. You just need to stop it from rocking side to side.

I always add a third rivnut to the frame as well to give a more secure fixing. You can buy 5 mm rivnuts from Ebay, and you can install them with a 5mm cap screw and a two flat plates with holes in. No need for the special tool. Drill the hole in the frame to be a tight fit. Tap the rivnut in. Place the plates with the hole over it with the holes in line. Insert the cap screw and tighten it with one hand while you hold the plates down with the other. If the rivnut starts to spin, insert a screwdriver between the two plates and lever them apart so that you're levering up the cap screw to form the rivet underneath. That should clamp the rivnut enough so you can finish off by tightening the screw. Take the screw out. Job done!

 

[Marc Webster]

That might work. You just need to stop it from rocking side to side.

I always add a third rivnut to the frame as well to give a more secure fixing. You can buy 5 mm rivnuts from Ebay, and you can install them with a 5mm cap screw and a two flat plates with holes in. No need for the special tool. Drill the hole in the frame to be a tight fit. Tap the rivnut in. Place the plates with the hole over it with the holes in line. Insert the cap screw and tighten it with one hand while you hold the plates down with the other. If the rivnut starts to spin, insert a screwdriver between the two plates and lever them apart so that you're levering up the cap screw to form the rivet underneath. That should clamp the rivnut enough so you can finish off by tightening the screw. Take the screw out. Job done!

As for rocking side to side, I would still try and use the bottle hardpoints on my bike but the area that is unsupported could be supported with one of my mounts. I could still use velcro since all it is doing is giving support in one axis and the bottle mounts deal with the roll.

 

[Deleted member 4366]

I'm not too sure that you understand the problem. When you put a flat surface on a round tube, it can roll around the tube. In the case of the battery, that will break the two 5mm screws or rip out the rivnuts. You have to hold the flat plate rigidly at a tangent to the curve.

 

[Marc Webster]

Hello D8veh,

Yes I do understand. The mount I designed is actually patented to do that exact thing. My mount contacts the tube at dual tangent points and with the rubber feet it can resist a lot of torque. I figured I'd still use the bottle mounts and then add one or possibly two of my rubber feet mounts to also help support any cantilevered load. This will be on a 700c Commuter so it wont see to many jarring loads from inertia that a mountain bike may put on the battery. Well I suppose if I ride on crappy asphalt it might but likely much less than a mountain bike setup.

However, I do note the concern and appreciate all the help and advice and will do the best I can to mitigate too much load on the bottle adapters..