Front wheel Friction drive

[artteth]

Any updates?

 

[ferias77]

Any updates?

802km with the friction drive !
I didn't have time to make the video.

A photo of the complete system :


Mounted on the bike :


It works perfectly when it's dry. But it slips when it's wet.
I have to make a knurled roller, like EVTodd...
I replaced the friction drive with my Q100 hub motor, waiting for this knurled roller.

 

[EVTodd]

Any updates?

802km with the friction drive !
I didn't have time to make the video.

A photo of the complete system :


Mounted on the bike :


It works perfectly when it's dry. But it slips when it's wet.
I have to make a knurled roller, like EVTodd...
I replaced the friction drive with my Q100 hub motor, waiting for this knurled roller.

As much as I like the knurled roller I use it probably won't help a lot in the wet. I think the sandpaper wrapped rollers might be better for that. I think the big problem is how much friction drive flings water everwhere. I gave up using it in the wet right away.

 

[ferias77]

As much as I like the knurled roller I use it probably won't help a lot in the wet. I think the sandpaper wrapped rollers might be better for that. I think the big problem is how much friction drive flings water everwhere. I gave up using it in the wet right away.

Do you mean that you have slipping with your friction drive on the wet, even if there is a knurled roller ?

 

[EVTodd]

As much as I like the knurled roller I use it probably won't help a lot in the wet. I think the sandpaper wrapped rollers might be better for that. I think the big problem is how much friction drive flings water everwhere. I gave up using it in the wet right away.

Do you mean that you have slipping with your friction drive on the wet, even if there is a knurled roller ?

Yes, I have a lot of slipping in the wet with mine. The knurled roller is great in dry but is terrible in the wet.

 

[amberwolf]

Something I've suggested before but I don't think anyone has tried yet, is to add a "brush" (like a floor scrubbing type with stiff bristles and a lot of surface area, long and narrow), somewhere before the roller on the back of the tire, mounted lengthwise such that it helps brush off mud and water.

It could be mounted on a lever such that it is only engaged (by cable, perhaps an old friction lever shifter) when needed, and only to the "depth" that is needed.

 

[EVTodd]

Something I've suggested before but I don't think anyone has tried yet, is to add a "brush" (like a floor scrubbing type with stiff bristles and a lot of surface area, long and narrow), somewhere before the roller on the back of the tire, mounted lengthwise such that it helps brush off mud and water.

It could be mounted on a lever such that it is only engaged (by cable, perhaps an old friction lever shifter) when needed, and only to the "depth" that is needed.

That's a good idea but I think any amount of water at all will make a metal roller (knurled or not) slip. The brush wouldn't really dry anything. Glued on abrasive material seems to be the way to go to stop wet weather slipping according to others that have tried it.

 

[EngineerDog]

Hey great looking build! Just wanted to say that my own friction drive build is also completely rendered useless by rain. (I used the can of the motor rather than a knurled shaft to keep it simple.) I've been experimenting with sandpaper glued to the drive with good success at improving traction but at the cost of wayyy too much tire wear. I used 80 grit, so perhaps something on the extra fine side would be better.

 

[ferias77]

Thanks for your reply EngineerDog.
I will try sandpaper, but as you mention it, I am worried about tire wear...
The solution may be rubber on the roller... I will try to test it.

 

[ferias77]

I used my hub motor during the winter.
But now, I want to use my friction drive again, and I need it works on the wet. :wink:
I think using an inline skate wheel to replace my aluminium roller. The friction should be really better, without the tire wear of the sand paper solution
Dis someone already try it?

Hidden Power sells now a rain roller :

http://hiddenpower.eu/shop/en/home/10-hiddenpower-rain-roller.html
Does someone know the material of this roller ?

 

[Hillhater]

That looks like just a "grit" coated metal roller ..at a guess !
You need to have a "sharp" edged grit surface to break through the hydrodynamic layer of water on the tire. I suspect any roller surface with sharp enough grit to be effective, is going to increase tire wear