Once you spring for a Zilla, the point is moot. The only reason for a transmission is to try to get good acceleration and a high top end out of a moderate motor controller combo. A Zilla has plenty of overhead to accomplish this with a single motor... unless of course you are talking about Killacycle type performance. I don't think anyone on this list has a bike that even the lowly Z1K low voltage (156 volts) model couldn't make scary fast from 0 to 80+ mph. The problem is most on this list are dealing with 48 or 72 volt controllers in the 300 to 400 amp range and a single gear ratio which means you have to choose between good acceleration or a higher top end. Multiple gears could give you both with a much smaller cheaper controller. Don't get me wrong, think your solution is the correct one because it is the least complicated least space solution. I just don't think multiple motors and parallel shifting are necessary on anything short of a drag bike. If you really want more performance forget the transmission and buy a stronger controller with a motor that matches. Any of the common 6.7 inch series wound motors and above should be up to the task of dealing with more powerful controllers. damon
Date: Thu, 3 Apr 2008 20:36:30 -0400From: [EMAIL PROTECTED]: [EMAIL PROTECTED]: Re: [ElectricMotorcycles] CVTs vs trannys and power shifting I think if you look closely you'll see a sport bike transmission is so tightly packaged you won't have room to fit covers and seals to close it up. Not to mention carving away the engine side of the cases and mounting the resulting metal potato. How about a completely different approach - why not get the effect of a transmission with electronics? A Zilla controller will properly (important concept) shift two motors from series to parallel and back. If you have two motors they can each be smaller than a single motor. I'm thinking the ADC 5.5" series looks promising. Jim Husted might be able to dig up something even more suitable. There are a number of advantages with this idea. More comm area, "shifting" is ultra smooth because there is no change in rotational speeds, and the mechanical implementation is WAY easier. It is no doubt pricey (less so if you scrounge), but you might spend more in custom machining and reworking to adapt a transmission. It should be pretty easy to get a two-motor setup to work well first time out. One important consideration: The S-P shift can be made automatic for cars (senses current draw and shifts at a programmable point), but you want it to be manual on an EM. The shift results in a step-change in rear wheel power that could mess with your traction. Better to treat it like a normal two speed transmission that you shift, just like any other motorcycle. Except there are no gears. When you think about it, this achieves exactly the same thing for an EM that a gearbox does for an ICE. Gears on an EV are not typically the best solution. When we use them it's usually only because they came with the donor. Chris On Thu, Apr 3, 2008 at 2:25 PM, john fisher <[EMAIL PROTECTED]> wrote: > As to using a sport bike trans, that would be an idea. The only> oiling for > the trans is a splash oil. The shafts run on ball> bearings. So if you > could enclose the case, you'd be all set.yeah I was assuming enough skill to > be able to close up the box to keep oil inside. _________________________________________________________________ Use video conversation to talk face-to-face with Windows Live Messenger. http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_Refresh_messenger_video_042008
