I've talked to just a couple that are quite happy with the K91 and actually said its more than they needed. And they're both running under 4:1. I'm just going to test some ratios out, but don't think its worth spending money right now without knowing. It might have more to do with the weight of the vehicle being under 480 stock. I've seen some 1000cc/1100cc, and I think they might be too heavy for it with a 4:1.
I think you're right though, I may be suffering range/acceleration for top speed, but the speed isn't my concern really... I'm likely going to be going 45mph or less. I just want to see the thing on the road, running. And I'm sure you know as well as anyone, these EV's are in a constant state of improvement. Once I have batteries, motor and controller tuned in, I can decide if a different ratio helps. Thanks for the input though, now I know you're not just one of those guys that quotes Bidwell's book as the bible. It may be a good reference for an Etek, but with a different motor, like the ADC or D&D, its in a different class due to RPM's, cooling, build quality and voltage rating. Sorry if I came off as harsh, but so many people have emailed me, commented on my blog and msg'd me on the forums telling me to rethink things because of Bidwell's book on a Ninja. Its a great guide for someone that wants to use a small bike, an Etek and be limited. I wanted a nice looking bike, good performance and not have issues with the motor breaking. He also used a certain set of products. I'm helping design my own (charger/bms/controller/monitor/display) with a company in Portland called Synkromotive. Take care, and great looking bike... your Frankenceptor and Ben's were the reason I went for the interceptor... I decided on the 86 after I saw it. Travis On Mon, May 5, 2008 at 10:15 PM, Jeffrey Blamey <[EMAIL PROTECTED]> wrote: > In my 500 Interceptor I am using the PMG which was built for 72V and > rated for 18HP and 28ft/lb of torque at 200A, now unless the Germans > used a different method of computing power I'd say the PMG is pretty > stout for a 25LB motor. The Etek is not quite the motor the PMG is > (too darn expensive tho); two bikes, same ride in miles, similar > sized bikes, me the heavier rider by 30 lbs on my Franken'ceptor, the > Etek was too hot to hold my hand on (don't know the internal temps), > the PMG warm but reasonable. The problem with Eteks the motor was not > designed for 60VDC or more, high amps, proper cooling, or a decent > rotor clip design (previous posts went on about the clips). I am not > dissing the Etek, I think it has been over-amped and abused when it > has failed. I think if you over-amp the Etek and it can't move the > cycle any faster (mass/wind resistance) the extra amps turn into heat, > the clips/solder let go, and the rotor comes apart - not because it > spins too fast. > > I am using the Altrax 300 Amp controller and find it more than > adequate for the PMG, and it never gets very warm. 450 Amp controllers > are for motors that can handle that. And for those thinking I dislike > series wound, my next project will probably use a D&D series wound and > a harley trans because I can handle the weight of both in the three > wheeler on the drawing board. Check out Gary Krysztopik's 3 wheeler on > Evalbum, I have been planning a similar roadster more on the lines of > 1500lbs so it is still a motorcycle. > > Anybody have experience with the new improved Etek? > > A fairly quick scan on Evalbum: Seems there are more bikes with Eteks, > fewer with PMGs, fewer still the Mars and then a couple with pancake > AC motors; ratios 5:1 and higher are used in more than 80% of those > bikes to good effect. A very few of the bikes have Series wound > motors, do have some in sub-4:1 ratios but note by their owners a lack > of acceleration. A couple have high 4s which sounds more reasonable. > If your motor is indeed capable of 5000 rpm then let it get there, > theoretical 70MPH+ speeds with 3 something to 1 ratios and achieve > decent range are pie in the sky, the horsepower requirements to fight > wind resistance at 45+mph are well documented. Go for the > acceleration and range (let the motor work less, loses less amps in > heat), that is what a EMC was made for. For those wanting CVT check > out Ray Wongs bike (3:1>>1:1 CVT with a 3:1 fixed ratio on final > drive), Dale in NM has a CVT for sale, save yourself some bucks. > > BTW: When I went through Evalbum just now I saw a lot of wishful > thinking in the range box on Evalbum. Be truthful guys and gals... > 75-100mph, 40+ mile range? Florida flat landers or hills and > mountains? At what level of depletion? For a minute there I thought I > was reading the Tabloids... > Aliens found at root of electric car demise ;-) > > Have fun, Jeff > > > On Mon, May 5, 2008 at 7:26 PM, Travis Gintz <[EMAIL PROTECTED]> wrote: > > could you reference your sources? > > > > I've found that that is not true at all, as I've been in direct contact > with > > motorcycle owners using the ADC A00, A89 and K91 motors and NONE of them > use > > a ratio that high. Thats also a reason the eteks overspin and overheat, > > because they're spun too fast and don't have adequate cooling. It can't > be > > spun lower because of its torque limitations (32 ftlbs, compared to my > 50+). > > Also, the HP is 15, mine maxes out around 19 or 20. The rpm maxes out > around > > 3400RPM, mine is above 5000. Its got a much wider power band, better > cooling > > (built in fan) and completely rebuildable. > > > > long and the short of it, its got more guts than the Etek, so I can't > really > > go on what chain/ratio other people used. > > > > And don't worry, I did weight/torque/acceleration calculations before I > > decided on this, while its not going to be what the original bike gave > me, > > it will give me great acceleration, great range and good high speed. > > > > > > > > > > I think most of the bikes as a compromise > > > between acceleration and battery range are more in the 5:1 to 6:1. > > > > > > > -- Travis Gintz 1986 Honda VFR DC conversion Http://blog.evfr.net/
