My fuel rate is quite inconsistent, i.e. 40 m.p.g...49 m.p.g.... Researching this issues, I came across a site where one logged and charted his fuel rate from his R80RT 1986. His average was approximate 45 miles per gallon and his best was 68.3 m.p.g. Why such a variable range? Had my values adjusted, carbs balanced...I am certain there are many causes and effects. Is this machine known for this?
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1986 r80rt fuel mileage
- Thread starter Bikemike1
- Start date
68.3 mpg? Did he live any Canada by any chance?? Wow, to get that kind of mileage (imperial gallons or not), I think you'd have to be traveling downhill most of the tank!! Plus, how do we know that his speedometer is proper for his final drive?
There are truly a lot of variables and it's probably most connected to the right wrist. Drag goes up by the square of the speed, so it doesn't take much push the mileage down. Tire pressures, road surfaces, type of driving...are you droning along at one constant throttle setting or are there frequent stops?
I don't think the R80RT is known for any more variability in fuel mileage than any other. Actually, I think some are worse, barely getting into the 40s.
There are truly a lot of variables and it's probably most connected to the right wrist. Drag goes up by the square of the speed, so it doesn't take much push the mileage down. Tire pressures, road surfaces, type of driving...are you droning along at one constant throttle setting or are there frequent stops?
I don't think the R80RT is known for any more variability in fuel mileage than any other. Actually, I think some are worse, barely getting into the 40s.
lkchris
Active member
You'll have to go downhill to get 63.
One of the surprising things that goes against conventional thinking is that an R100RT is quite likely to return better fuel mileage than an R80RT. The R80RT engine spins a lot faster due to the rear drive ratio.
An R80 engine only needs to spin 1.25 faster than an R100 to displace the same amount of air/fuel through it. How about 5000 rpm vs 4000 rpm? That's pretty close to actuality.
One of the surprising things that goes against conventional thinking is that an R100RT is quite likely to return better fuel mileage than an R80RT. The R80RT engine spins a lot faster due to the rear drive ratio.
An R80 engine only needs to spin 1.25 faster than an R100 to displace the same amount of air/fuel through it. How about 5000 rpm vs 4000 rpm? That's pretty close to actuality.
The website that reported the 68.3 mpg is here:
http://www.fuelly.com/driver/ritz/r80
I wouldn't really trust the numbers from this person. It takes him a year to burn off a tank it seems. The previous fillup before the 68.3 doesn't show miles ridden or MPG. My guess is that he partially filled 10/15/11 and then "caught up" on the next fillup on 12/1/12 and didn't take into account the total miles ridden since the partial fill on 10/15/11.
Bogus data, really!
http://www.fuelly.com/driver/ritz/r80
I wouldn't really trust the numbers from this person. It takes him a year to burn off a tank it seems. The previous fillup before the 68.3 doesn't show miles ridden or MPG. My guess is that he partially filled 10/15/11 and then "caught up" on the next fillup on 12/1/12 and didn't take into account the total miles ridden since the partial fill on 10/15/11.
Bogus data, really!
