Gary- What's the final drive ratio? The reason I ask is that it is uncommon for cars to exceed 65mph in 2nd gear. Which means that the insight transmission is a bit unusual in that way, or perhaps the calculations are off by 10-20%? I only ask because 70mph seems pretty unusual for 6126rpm.
Seth Gary Graunke wrote: > > > From: "Thomas Shay" <[EMAIL PROTECTED]> > > > Subject: Re: shaft coupler material > > > Is it necessary to machine a coupling from scratch? It must be possible to > find > > something that fits the motor splines. Surely a motor doesn't exist that > nothing > > fits that the motor could drive. The center cut from a clutch disk could > > serve as the transmission end of the coupling. It seems two coupling > halves could > > made and joined. > I strongly suspect that there is a European auto that fits the motor -- an > Opel, if I recall what Victor said. > (But then I'm probably having trouble remembering the material type from > this morning!). > > We also considered bolting two halves together as a backup plan, but our > first choice was to have a single piece. > > > Can the Insight transmission tolerate being driven at 10,000 rpm? > > While it certainly is good insurance to keep the clutch for this very > reason, I did calculate the RPM at various speeds, using an observation that > the Insight goes 70 mph at about 3000 RPM in 4th gear. Using the gear ratios > from the Honda Insight shop manual (3.461 for first, 1.75 for second, 1.096 > for third, 0.857 for fourth, and 0.71 for fifth), I calculated the following > RPM for various speeds. > > The numbers for second gear were > MPH RPM > 70 6126 > 80 7001 > 90 7876 > 100 8751 > 110 9627 > 120 10502 > > Since I don't plan on going that fast (and we think the top speed due to > aero drag is about 110 for the 54 KW I'll get from 240V anyway), 2nd should > be ok. The redline for the Insight ICE is 6000 RPM, so I expect the > transmission will be ok at 70. Of course, lower RPM's would be easier on > both the motor and tranmission. > The torque is still maximal with the AC drive at 240V until I get to 4200 > RPM, somewhere over 45 mph, but should be ample for normal driving even > above that. > > I also recall Sheer's post which indicates that he obtained somewhat higher > efficiency on his trip from Portland to Seattle using 3rd and 4th gears. I'd > like to check this out before going to fixed gears. The efficiency gain > might itself justify leaving the clutch for frequent highway drivers. In any > case, 2nd should be just fine around town. > > Gary > > > Tom Shay > > > From: "Gary Graunke" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Wednesday, October 02, 2002 2:55 PM > > Subject: shaft coupler material > > > > What material is best for a direct drive coupler? I'm having a coupler > made > > > that connects an A/C driver motor (max RPM 10,000) to a Honda Insight > > > transmission shaft. The piece will be machined with male spline on the > motor > > > end, and a female spine on the tranmission end. The max torque is 92 > ft-lbs. -- vze3v25q@verizondotnet
