Hello to everyone! This has turned into a pretty epic conversion! I want to get this bike riding ASAP! I want to know what the RC motor is capable of! I want to be screaming through some woods like a banshee!!
At this point I would like to say that with a 20" wheel we could have the whole system checked for week points and to find out if it works at all in around about 2 weeks (asuming the throttle signal can be sorted for the rc controller)! The last piece of hardware has been designed and as soon as the ali turns up it will be in the hands of our rather capable Machinist to get it finished for us!
I think that even though D wouldn't be particularly happy about having a 20" wheel, it would get this thing off the ground and proven so quickly. Then you could muck about finding a way to keep the 24" wheels and mounting the motor for as long as you like! The point is that it would be working and everyone can see what else needs changing rather than stabbing in the dark! At this point we personally have no idea how the system will perform. I'm not just talking about the motor and controls anymore here. I'm thinking about the whole drivetrain setup. Has it ever been used before? what are the limits? Etc, Etc, etc. test, test, test. can't do that till the motor is mounted! Which if left as is we can do!
We also need to know about weather or not we need to get the controller in good air flow or if it will be ok in the box. I mean look, there are so many unknowns that need to be addressed and I think we are concentrating on the least important right now! I will personally loan a wheel at no cost to get it moving. bearing in mind that to make the motor mount for the seat tube would be a peice of cake and cost f-all, so that if the wheel size is the only issue after that then you have a clear direction to take it in. We've just been looking at how to mount to the down tube and it is going to be a pig! :-(
My worst fear is that it takes another 6 mounths to get the motor mounted to everyones satisfaction to find that everything else sucks and it has been a total waste of time and yet another drive solution needs to be found! Personally I don't think it will come to that, but I would like to know sooner rather than later!
Basically to me it's a no brainer about how to get this moving in the right direction. Fit a smaller wheel EVEN if it's just for one ride, see if everything else works, then at least I know it's not a futile effort to get the 24's fitted. PLUS, it is not invasive to the frame or any of the other components and cost absolutely f**k all!
Ok pic's time!! Yay!
The first two are of the 20" wheel with the motor in the CLOSEST position to where the composite sproket will be mounted. Giving minimal chain langth and keeping everything tight. On full extention there is acrs of room between the motor and tyre; 3", at least the same thicknes as the mototr again. Under full compression, there is still another inch to go leaving plenty of room for a motor cover etc. So that's what I think we should do! Getting it moving!
The next lot are with the 24" rear wheel, bearing in mind I would always keep the front wheel 24" for better ground clearance and bump absorbtion bla, bla, bla.
So with the 24's you can just about squeeze in the motor on the lowest possible position, and get a small amount of clearance in the highest position which would be better for chain rap on both sized wheels regardless. But in the highest position, there would be no room for ajusting the chain tension after it starts to stretch! Anyway, with the 24, you would just about be using the standard amount of SAG the sus would normally give you and it would be rubbing the crap out of the motor. Basically there is no where near enough room for the motor to be mounted on the seat tube with 24" wheels, so that is that out the question. Even with modified seat tube! Fully compressed without the motor in the frame there is a maximum of 1.5" gap to put it in!
The last two pics are of a possible placement for the motor with the chain and sproket in situe so you can see what's what!
If I've rambled, I'm sorry but I want this bike finished it's been collecting dust long enough!!