Fuel consumption ?

[Sibbo]

I've quite carefully checked my fuel consumption on my ST over quite a few tankfuls and it comes out at 6.4 litres per 100 km or 37 mpg US.

How does this compare with other machines ? I figure it's a bit higher than it should be .

[SteveD]

37mpg is poor.

Over the weekend of mountain riding on my R100RS the poorest consumption I had was 11kpl x 3.8 = 41.6 kmpUSg or 26mpg.
The best was 13.5kpl or 7.4 litres per 100kms, 51 kmpUSg or 31.8mpg
One co-rider said mine smelled rich when following me. It was difficult to start at Omeo (high country) with full choke, but when the choke was closed it started ok.

Traditionally I have used around 15kpl, or 57 kmpUSg or 35.6 mpg.
My jets and needles aren't that old, but I do need to check the needles are on the 2nd notch in, and not the 3rd.

I've x Litres x 3.8 to convert to Gallons.
I've divided kmpUSg/1.6 to get mpg. Is that correct?

[khittner1]

Both of yours sound pretty thirsty. I get 40-46mpg out of my '84 R100RT, but it rarely sees the high side of 4500rpm.

[Sibbo]

37mpg is poor.

Over the weekend of mountain riding on my R100RS the poorest consumption I had was 11kpl x 3.8 = 41.6 kmpUSg or 26mpg.
The best was 13.5kpl or 7.4 litres per 100kms, 51 kmpUSg or 31.8mpg
One co-rider said mine smelled rich when following me. It was difficult to start at Omeo (high country) with full choke, but when the choke was closed it started ok.

Traditionally I have used around 15kpl, or 57 kmpUSg or 35.6 mpg.
My jets and needles aren't that old, but I do need to check the needles are on the 2nd notch in, and not the 3rd.

I've x Litres x 3.8 to convert to Gallons.
I've divided kmpUSg/1.6 to get mpg. Is that correct?

Try using this page Steve . http://calculator-converter.com/l_100km ... 100_km.php

[SteveD]

Try using this page Steve . http://calculator-converter.com/l_100km ... 100_km.php

Thanks. That confirms my calcs were in the stadium at least!

[fig]

My /5 gets 45-47 mpg

[jagarra]

My /6 is in the range of 40 mpg.

[Duane Ausherman]

It seems that many think that these bikes that appear so similar should get similar mileage. Not so. In my day, the highest mileage bike was the R90/6 and they got 55 mpg commonly. Some even got 60 mpg. At first I didn't believe my customers, but after enough reports I accepted it. Besides, it is hard to deny meticulous record keeping.

Average riding, what ever that is, should nearly always come in around 40 mpg or better. Even our highly souped up race bike got 27 mpg.

[Major Softie]

Odds are that new needle jets and needles will make a difference. If they are original, there's no doubt that they've rattled themselves a little larger by now.

Checking your float bowl level/float weight is another important check, but, as I said, if original, your needle jets are bigger than they used to be.

[bbelk]

Both my R65 and my R90 are in the 40 - 45 MPG range with the R65 falling off fast above 60 MPH and the R90 falling off above 70 MPG.

I also suspect, but have never really tested, that the performance picks up at lower speeds. It would be interesting to know what the max range speed and RPM would be. It was actually in the owners manual on my 1968 Bridgstone 175 and it was something like 25 MPH in third.