Gas Mileage

[merrittgene]

I'm curious about the gas mileage that other people get from their bikes, specifically the K100.

I have a 1986 with 50K miles and I averaged 36.7 over the last 12K miles, with a few highs in the 43's.

I tend to drive 75 on the interstate, which results in 37's.

My question is, should I expect more from this bike? :dunno

[roy]

On my 85 K100 I averaged mid to upper 40's over the three or four tanks I checked it on last fall. Note: Speed limit in Illinois is 65 so this will also make some difference.This should improve this year since I gave it a much needed tune up this spring.

Things to check that I found marginal to bad on my bike.

1) Plug wires: 3 out of four were in excess of 50% over rated resistance when checked.

2) Vacuum lines from cylinder #4 to the pressure regulator, dried and cracked.

3) Vacuum line from Cylinder #1 to vacuum switch mounted on back of throttle body rail. Both a royal pain in the A** to change.

4) Throttle body to head rubber mounts. Two out of four were starting to seperate from the steel mounting base.

5) Connection on throttle position sensor. Mine was real coroded.

6) "L" shaped vacuum hose that goes between the crank case and plastic intake box above the throttle bodies. This can be seen by looking from left side of the bike. This hose has a tendency to crack over time.

Some of these are much easier to check than others.


Hope this helps.


When the weather gets more cooperative I will be able to give an update on mileage if you want.

[Mudbug]

on how you ride.

On my 91 K100RS, I get high 40's, sometimes 50 mpg, especially on the highway, 65 - 70mph. If I keep the rpms up, 5000+ in each gear, then mileage suffers. I found that the 4000 to 5000 rpm range works fine and gets pretty good mileage.

[deilenberger]

I'm curious about the gas mileage that other people get from their bikes, specifically the K100.

I have a 1986 with 50K miles and I averaged 36.7 over the last 12K miles, with a few highs in the 43's.

I tend to drive 75 on the interstate, which results in 37's.

My question is, should I expect more from this bike? :dunno

This is not unusual mileage for a K100RT. You can hope on longer trips with all interstate, running about 70MPH to get up close to 50MPG, but it requires a steady throttle hand.

[naddy100]

{snip}specifically the K100.

I have a 1986 with 50K miles and I averaged 36.7 over the last 12K miles, with a few highs in the 43's.
I expected more from mine as well (1987 K100LT, 93K). When I drive 75, the mileage is about 37mpg. When I drop to the 60-65 range, I pick up a mpg or so. When I slow to Mississippi two-lane speeds, my mileage is 43. I think I'd get 50mpg only if I coasted down a hill (or, who knows, perhaps the steadier throttle hand).

I've occasionally wondered about a leaky airbox, vacuum hoses, and such, like other posters have suggested. I haven't done anything about them.

I've also thought that my barn-door fairing has some effect at 75. It's great, but I speculate that it has an effect compared to a cafe style fairing with me hunched over the tank.

Noel

[Bruce_C]

Gene
My mileage is about the same as yours. I am riding a '85 K100RT with the tall euro windshield. It has 55,000 mi. on it. My mileage varies from the low 40's in the 50-55mph riding range to 33-38mpg at 70-80 mph depending on wind direction. I don't think it would get 50mpg going off a cliff with the engine shut off.

Bruce C :)