So my question goes out to all e-boarders with pneumatic wheels: what is your battery and gearing setup? and what are the sweet spots (i.e 15/36 and 10S for urethane wheels, but what about pneumatic?)
There are a lot of builds with pneumatics in the build threads category here on the forum, check them out using the search feature. Here’s my build with pneumatic wheels. I use 14/60 gearing and I love it.
Hey there! Not a eMtb user yet, although been looking through a lot of stuff related to this matter.
It seems that the most widespread is something like 1:4 or 1:5 gearing ratio. That would translate to 15t : 60 (belt drive), or in some cases 12t : 60 (chain drive) or 16 :72 (1: 4.5) or 15:65 (1: 4.3)
I think what matters most is what kv rating motor and what battery setup you will be using.
I’m still not entirely clear on this one also as the opinion varies greatly. I’ve seen people using setups starting from 192kv to 300kv. Although, for the higher kv the gearing ratios are also higher, to compensate for the lack of torque, 300kv might have for example be geared with 1:6, compared with 192kv and 1:5.
As you probably already know that also impacts the size of the sprocket/big pulley. There are limits how far/big you can go relating to the hub/tire size you are going to have for your emtb.
As of now, i’ve settled for 4,3 : 1 ratio (15:65)… as these are the pulleys I can easly get.
I think what would be needed is a calc, which includes weight, motor torque, wind speed and all of these other factors which might influence the future torque/speed of the build.
As I have not built one yet that is all I’ve read / found out so far… so there may be some other great tips / suggestions from other users about this matter.
As a final opinion I would recommend you to go with 1:4 to 1:5 as that is what most people are using. It also seems that it greatly depends on your drive system, will it be belt driven or chain driven. For chain systems I think it is easier to have higher rations than it is for belts. Someone can correct me If I am wrong but it seems that you can get smaller pulley (12t for example) do the job for you (in chain system), where with belt drive system such pulley won’t have enough teeth in mesh (in grip with belt) and it may slip a lot more than it should compared to the other.
So, if you are torque inclined go with 1:5, if speed is more important matter (more flats, just asphalt / paved road) then you may get along with 1:4.
I recently completed my first build but I am desperate to jump to pneumatics. Alinedrive’s 5" stuff is sold out so I was wondering if I can get it from somewhere else.
@treenutter The pneumatic wheels that you are using are these the same wheels as skikes kids available at
if so, what else do I have to but from alien drive systems to get it working?
doing the same thing now. skike wheels need 1cm taken off of the rim to fit the truck.
Oh cool. Maybe you could put a couple of photos, later, to tell us how you did it.
also @Maxid, what else do I need to buy from aliendrivesystems to
I am assuming
pulleys : http://aliendrivesystems.com/product/hub-pulley-wheels/
hub adapter: http://aliendrivesystems.com/product/urban-5-hub-adapter/
Or did you use something else?
the parts just arrived - will try to use a lathe tomorrow to remove the 1cm.
I will probably 3D print everything else (the bigger the diameter the better a 3D printed pulley should hold).