Cro Motor v2 Dropout Dimensions with 8/9 freewheel

[madin88]

a 52T with a 16T (rear) is 38kph with 90rpm...thats not really much....

iam still waiting for a Price from Zelenavozila for a Schlumpf Drive.
atm i have no crankset, so the price for a schlumpf maybe only the half "on top" of a normal crankset. (hope so ;P)

go outright with the schlumpf will indeed safe money if some has not yet a crankset. hmm are there pedals included?
i see zelena vozila normally offer the schlumpf only with the warp frame. hopefully they make a good unit price.

52t @ schlumpf should be fast enough with a 16t on the motor
what program this is you can choose those chainrings and wheel diameter? its nice..

 

[Merlin]

www.ritzelrechner.de

 

[dirtbiketoebike]

Tried the 3 speed one on ebay for $10 free ship. The smallest gear is 16 tooth tho, I cant pedal fast enough going top end,the next 2 bigger gears are nice if the bike breaks down or slower riding. Im looking for maybe a 10 or 11 single gear since I cant find it in a 3 speed. With the 10 or 11 tooth I think using the 3 front sprockets will be fine for me.

 

[zombiess]

Someone on here did some aerodynamic calcs and found that depending on the bike pedaling over a certain speed will hurt your range. I think it was somewhere between 42-56kph depending on the aero of the setup.

 

[Obiwan007]

There are no 10 or 11 tooth single speed freewheels to my knowledge. The problem is simple geometry. The threaded portion of the hub is too large a diameter. That diameter plus the bearings and the other internals of a freewheel take up too much room to pack between the threads and the diameter of anything smaller than a 14 tooth cog. The reason that 7,8 and nine speeds can go as small as 11 tooth is that the last few cogs reach out beyond the threaded portion of the hub so these cogs can be made smaller than the diameter of the hub threads. It is for this reason that the spacer washers are that small size, so they can fit inside the narrow opening of a 7 speed freewheel with an 11 tooth cog on the end and a hole that is smaller than the hub threads. I bet someone could make one with needle bearings that could get small enough for a 12 or 13 but I have not seen one yet. Market opportunity knocking for the person with the right skills. Beware, there are some single speed freewheels for BMX with smaller tooth counts but they are for a smaller hub thread and they won't fit on an DD hub motor. If you find one that has anything smaller than 14 and fits our thread size I will be the first in line. Obiwan

 

[zombiess]

Found one Obiwan, but its a prototype for the Cromor only. I asked Greyborg to make a metric freewheel adapter and they have, but we are still testing. I have a test adapter being delivered to me in my next parts shipment. I saw the need for 13 to 15t freewheels.

It is going to take several months before these are final. I just wanted to let you know we at in the process of addressing the small free wheel adapter. This will really make a big difference for those like me who run small diameter wheels.

 

[Obiwan007]

That is awesome Zombiess. So how does it work? You say it's an adapter? Does it replace the threaded part of the side cover? Does this then make the threads capable of accepting the BMX freewheels? Hmmmm...the possibilities! Do they make multi-cog BMX size freewheels? I wonder if there is such a thing as a BMX 3speed freewheel. I'll have to do some research. Obiwan