Woosh CD kit? Would it be compatible with a Aluminium road bike?

[DCUK6]

Hi,

Just reading the other thread about the hopefully upcoming Woosh CD Kit. (didnt want to clog it o#up with stuff not related to the subject)

The CD kit | Chain Drive Electric Bikes from Woosh | electric bike sales & hire

I really like the look of this kit as it will hopefully let me select a bike seperatly.

Just having a quick look i would properly be hoping to fit it onto something like the
Carrera Zelos
or
Carrera Virtuoso Road Bike



I know the supplier is saying that some frames are too weak. Any ideas on how to tell which frames these are?


Now going to sound really newbie ish, it looks like the kit would replace the front gears. Is this corect? Would the gears on the kit be compatible with the rear gears on these bikes as the smaller gear on the kit looks alot bigger than the stock one on the bike.

What watage motor are these?

Would it be available with the bigger battery. Dont think the battery is big enough.


Many thanks

 

[Deleted member 4366]

Hi,

Just reading the other thread about the hopefully upcoming Woosh CD Kit. (didnt want to clog it o#up with stuff not related to the subject)

The CD kit | Chain Drive Electric Bikes from Woosh | electric bike sales & hire

I really like the look of this kit as it will hopefully let me select a bike seperatly.

Just having a quick look i would properly be hoping to fit it onto something like the
Carrera Zelos
or
Carrera Virtuoso Road Bike

The Virtuso look a bit tasty.

I know the supplier is saying that some frames are too weak. Any ideas on how to tell which frames these are?


Now going to sound really newbie ish, it looks like the kit would replace the front gears. Is this corect? Would the gears on the kit be compatible with the rear gears on these bikes as the smaller gear on the kit looks alot bigger than the stock one on the bike.

What watage motor are these?

Would it be available with the bigger battery. Dont think the battery is big enough.


Many thanks

The kit uses notches cut into the bottom bracket to resist the torque of the motor, which is why there's some reservations about frames.. To me, this is a dodgy thing to do because it puts torsional loads on the BB that it's not designed for, so it could be risky with any light-weight frames. Also, there's a risk of metal fatigue in the long term that could cause the frame to crack next to the BB welds. Aluminium does not have a lot of resistance to constant torsional loads. Steel would be affected much less because it generally has a much higher fatigue resistance. From what Hatti said, the manufacturer has done some life-cycle tests with their frames is happy with them, so they at least should be OK.

If I were fitting the kit, instead of cutting grooves in the BB, I'd file off the dogs on the motor assembly and fit a tie-bar from a bracket around the frame to one of the motor studs; then the kit would be reasonably safe for even lightweight frames including carbon fibre if done properly. On the Woosh Sirocco CD, two of the studs are longer so that you can fit a chain-guard. Assuming the kit motor is the same, this is where I'd fit a tie-bar. All this is making a few assumptions, which I couldn't confirm without the kit in front of me.
The problem for a manufacturer is that every frame is different, so it might be difficult to make one bracket fit all, although GNG managed it. One would assume that the kit manufacturer chose their method for a reason, so I probably missed something; however, they do seem to have those reservations about what frames to fit it to, so steel frames might be OK, otherwise ones with a lot of metal round the BB and a nice thick BB shell.

You're correct about the front gears, unless you want to do a bit more DIY. I'm sure I've seen Tonaros modified for front gears. Rear gears should work as standard, but if you've got non-cassette gears, it would be better to change the wheel so that you can get a 11T top gear for more comfortable pedalling at speed.

Power is a nominal 250w, although it could probably be pushed a bit higher with controller mods.

The kit shown has a bottle battery with an integrated controller in the base. You could probably use any battery on a rack or anywhere you can fit it if you used a different controller.

 

[DCUK6]

Thanks,

So the weakness problem is just about if the two notches in the frame could handle the spinning forces from the motor and nothing to do with the weight of the motor.

Would the bracket you thought of work like the one at 1:21 in the video old_dave posted (below)? Im guessing this ype of bracket uses part of the frame that is designed to take a bit of load (holding the back wheel).

Im guessing the longer you make the bracket go down the forks the more it would spread the forces between the joints.

How to install iBike S03+ - YouTube

Im hoping at Redbridge there will a road bike, at least wih hub motor, ihave yet to ride a bike with no suspension.

 

[muckymits]

I am tempted with a belt and braces job, do both. But I would need to have mine in the front like the folder, so think it would have to be a heavy buffer and clamp on to the main frame as its going to try and kick back anyway.

 

[Deleted member 4366]

That's one way of doing it, but, as a DIY project, I reckon it could be done easier because the Woosh motor has studs sticking out the motor that look like they were made for the job.

 

[muckymits]

Did you not take any decent pictures of this?

 

[Deleted member 4366]

Not yet, but Woosh provided this one. Incidently, my reply above was to DCUK6.

If you look at the bottom of the photo, you can see the stud sticking out. On The Sirocco, there's another one diametrically opposite, which meams that you could mount the motor in a range of positions. I can also see a hole at the inside of the BB, which looks like maybe removable pins are used as the dogs, which would make things easier, as no filing would be necessary.

 

[jackhandy]

it's difficult to see from the camera angle in that photo, but the chainwheel looks quite heavily dished; presumably to get it in line with the rear sprockets.
I should think that would make it diffucult to fit a second, smaller ring.

 

[Geebee]

Just of the top of my head, on a thinner aluminium bb could you not just fit a close fitting steel sleeve and either cut it to fit around the frame tubes to limit torque or run an arm off the tube and clamp it to the frame.
This assumes the dogs are tall enough to engage the steel tube, as either idea should not detract from the bikes looks after a paint job on it.

Just checked my racing tikes BB its aluminium but at least 4mm through the walls, should be fine, my other trike is all CroMo.