I agree. I have the 8 brush 6.7" ADC with a 72 V pack and a Zilla 1K. My gear ratio is 4.75:1 which gives me about the same top end and pretty snappy acceleration without overheating. me
On 8/6/07, damon henry <[EMAIL PROTECTED]> wrote: > I don't think that there is any general differences in the D&D and ADC > motors that are relavant to your application. > > There are two main things to consider when comparing similar series wound > motors, and they both have to do with how much current they can handle. The > first is the brushes. Looking at the size of the brushes and the leads > gives you a good idea of how much current they are designed to handle, but > be aware that even in just the ADC 6.7 inch line theses are not always the > same. There are 4 and 8 brush ADCs. On my motorcycle I have a 4 brush ADC > and it handles my 400 amp controller just fine. The second thing to > consider is thermal mass. Basically the more copper you have in a motor the > more mass it has to handle the heat produced by higher currents. Again, > sticking with just the ADC 6.7 inch line of motors there are several > different armature lengths. The longer armatures have more wire wrapped > around them and weigh more meaning it takes them longer to heat up to the > point that you have problems. Again on my motorcycle I have one of the > shorter ADC 6.7 inch motors, althouh not the shortest, and it handles my > riding without ever overheating. In summary, when compairing two similar > series wound motors you are generally better off going with the one that has > the beefiest brushes, and weighs the most. I strongly recommed working with > Jim Husted. He has access to lots of motors in this size because they are > commonly used as lift pumps on forklifts. He can pick you up a core for a > couple of hundred bucks, then build it into something special for a couple > hundred more. In the end you will usually end up with a rebuilt motor that > is better than brand new because he will modify it to fit your application. > The price is usually less than a brand new one will cost you, plus you > will have Jim to bounce any questions off of and he sends every EV motor out > with a little of his Hi Torque fairy dust :-) > > As far as the freewheel thingy, it sounds like a lot of effort and very > little reward. A series wound electric motor already freewheels very > nicely, so leaving everything connected works just fine. My motorcylce > rolls like crazy when I let off the throttle. > > Finally, I strongly suggest going with 72 volts for any motorcycle you are > hoping to ride at freeway speeds. It can be done on less, but going with 72 > volts makes it much easier to keep good acceleration and a high enough top > end. I'm running 54 volts with the stock 14 to 41 gear ratio. I have > decent acceleration and can just creep my way to 60 mph. With a higher > voltage controller I could change my gear ratio and have better > acceleration and a bit higher top end. > > damon > > > >From: "Seth A. Keel" <[EMAIL PROTECTED]> > >Reply-To: ElectricMotorcycles <[email protected]> > >To: [email protected] > >Subject: [ElectricMotorcycles] More on motors > >Date: Mon, 06 Aug 2007 04:00:53 -0500 > > > >Hello all, > > > >Great list. I've been following along for about 3 months now and it's been > >very helpful to hear the comments and ideas from the members. Travis' post > >has got me going, 'cause I'm interested in motors too. There is a 1975 > >Honda Gold Wing disassembled in my basement and I'm trying to figure out > >how to rebuild it. Which motor to get is the current question and it's > >such a pivotal one that the rest of the design is waiting for it. > > > >Here are a few questions that I'm struggling with. > > > >1) What's the difference in quality between ADC and D&D? > > > >2) Can a PMG-132 push my sled at 60mph for 10 minutes without overheating? > >There's another 5 mi. of city driving on top of that to get to my job. Can > >it be done on 60v or or should it be done with 72v? > > > >3) What's a typical watt/mi estimate for a bike that's around 1000lbs. with > >rider? I've been using 300watts/mi. in my calculations. Is that close? > > > >4) Do any of you use an overrunning clutch coupling, or something similar, > >so the motor shaft isn't directly linked to the final drive? An OCC is > >basically a freewheel. My diesel has a mpg readout in dash which, even if > >it's not perfectly accurate, definitely shows that disengaging the engine > >when it's not needed and coasting to stops saves a lot of fuel. I'd like > >to do the same with the EM without having to add a clutch. It would also > >eliminate any concern over the motor lockup issue that was discussed > >recently. > > > >Any thoughts or suggestions would be very much appreciated. Thanks, > > > >Seth > > > > > > _________________________________________________________________ > A new home for Mom, no cleanup required. All starts here. > http://www.reallivemoms.com?ocid=TXT_TAGHM&loc=us > > >
