MPG & Getting to Reserve

[Luca]

i suggest a simple thing to do,to understand when the bike will go in reserve.Firstly, as was said before,depends how you run fast,with full throttle your carbs will be dry very soon....try on a quiet street run and put off the petcock..feel the engine how became rough as soon as the fuel is finish in fuel hose.Remember this when you run,could be helpfull to anticipate the reserve.

Best regards
Luca

[stagewex]

There were basically two tanks. The stock tank was 4.5 gallons and the sport tank was the larger 6 or maybe it was 6.3 gallon tank. Personally, I think the smaller tank looks best with the rest of the bike. My bladder doesn't really benefit from all that extra gas in the tank

Definitely have to laugh at that. I said that I stopped for fuel as soon as I saw a gas station...I lied. First thing was a trip to the station restroom.

About 150+ miles times out to my bladder capacity at this point. I could probably use the belt pressure on my pants instead of the odometer as a parameter for getting to reserve. I'd need "Depends" if I went any further.

Here (below) is a sticker from the "Embalmers Car Club" that was showing off some old non-restored Rat-Rods the other night. I like their motto:

[Twocams]

That reminds me of a story. My youngest son (35) has been riding motorcycles from about age 12. We both ride BMW and he decided he wanted a new 2013 K1200S. Its about 400 miles from Sacramento to my house in Oregon. He was coming up to show off his new bike and we were going for a ride to the coast. He called me about 100 miles from my house and said he had a problem with his new bike. So I asked what he thought the problem was. Well he says "I guess the computer couldnt keep up with my 80-90 mph riding it said I had 2 gal. of gas left. And X amount of miles". I ran out of gas. What! Your $17000 BMW with 1500 miles on it, ran out of gas. He was able to coast to a gas station 1/4 away. I still give him hell about that and he still has the bike.

[stagewex]

Ran out of gas on a 2005 KLR I used to commute to work on. Claim is that on the average you can get 58mpg on those bikes. So even going onto reserve on my way to work I was not in a hurry to re-fuel for my 40 mile total roundtrip to-and-from home. One (1) gallon of gas in reserve BTW.

Ran out of gas of course just 15 miles into reserve... in NYC of all places. Pushed and pushed and then went looking for a gas station wondering what happened to all the gas?

Turns out the big fuel tank on the KLR sits so deep into the backbone/frame of the bike a lot of fuel gets caught on one side or the other of the bottom of the tank, and the cross-over doesn't help that much. If I had just leaned the bike over left and right I could have gone another 25+ miles. Oh well, one of those live-and-learn adventures.

[c8h18]

So here I am out with my buddies deep in the Pine Barrens of NJ and we pull up to a local but rural gas station to top off. Of course I close my petcog when I tank up. Was done fueling and got busy talking while waiting for others. We all pull out..me last. Less than a quarter mile down the road same thoughts you were having. What's wrong? how much will this cost? why is it just dying? etc..Got it to a flat spot on the side of the road to find I didn't turn the petcog back on. Embarrassing for sure and we all had a good laugh..Yep, very little warning when she runs dry.

As for gas mileage typically low 40's/gal. I wind it out and ride it hard so may be consuming more fuel then when ridden in a gentle manner. I typically have it out on the slab just humming at 75-80MPH.

I once put a bit more than half a tank of blue AV fuel mixed in with the 93..(that was interesting and I was out of fuel options). MPG was slightly higher but that could have been for many reasons. These days I just run the 91 or 93 octane, the 87 seems to create some ping on my bike - 1969 R60/2.

[stagewex]

Took the advice and started using the next lower octane grade. From High-test 93 to mid-test 87. About 4-5 tankfuls so far.
No pinging and I am getting almost 20 miles more per tankful before hitting reserve than before when I was using the 93.
Yesterday I hit 178 miles at reserve which is my best ever. It was usually at the very best 157 miles if you re-read my first post in this thread. I may try the lowest grade of 84-83 next full tankful. This actually fits in with the milage you are supposed to get as mentioned in the original owners manual.
These have all been 100+ to 200+ long highway rides so the conditions have been constant with little stop-and-go traffic.

Also seems to come to idle better now after a long run. Guess I was wasting my $$$ on high-test.

[Slash2]

Perhaps the BMW manual wasn't considering the weight of today's rider. While 220lbs is an average weight for today, I'd be willing to bet there weren't many guys of this size cruising beamers back in the 60's. The average man weighed about 165lbs in the 60's vs about 195lbs today. So if you factor in your extra 60lbs to the estimated mileage, I'd say you're doing pretty darn good.

At 165lbs I switch to reserve at 205 miles with steady consistency. That said, if I'm cruising on the highway (which I avoid at all cost) the warning is non-existent. One minute you're cruising wide open, the next it's like the plug was pulled and you're testing your speed and reflexes.

I just replaced the original Everbest petcock on my /2 with a new reproduction Everbest which really does look great. Exact in all ways aside from the cork which they've replaced with neoprene. I found mine on ebay from seller Spikebuck who has interesting bits and pieces from time to time. Another member mentioned that it's a bit tight in actuation, and while I'll agree with this, if you just give it a little workout before installation it loosens up and actuates nicely.

I've got a few old Honda's from the early 70's which give minutes of warning through the subtle burbling and buppety bupping of the engine's steady song. I've run out of gas on several occasions on old Honda's but as they have left-side petcocks and generally no crossover on the 4's you can stop, pop the seat, pull the tank off and dump the gas from the right to the left and get another 10 miles or so.

[schrader7032]

I've run out of gas on several occasions on old Honda's but as they have left-side petcocks and generally no crossover on the 4's you can stop, pop the seat, pull the tank off and dump the gas from the right to the left and get another 10 miles or so.

That's something to remember with the /5-on bikes. There are two saddles and despite having two petcocks, there is usually gas below the reserve straw in the tank...provided the straws are still there. Take the tank off, roll the gas from one side to the other, maybe get you another 15-20 miles down the road.

[jrapose]

Boy, did I ever learn.... burned a hole in a piston...what a mistake.... if I can't get premium fuel I walk... it's that high compression of the R69S.... I guess it would run in a lower compression R50 or R60 but that lesson I learned hurt a lot...

Joel Rapose
1966 R69S

[stagewex]

Seems to run fine and better on a lower compression r60. I'll see if switching to the lowest grade makes any performance difference in the negative. Right now I'm pretty happy with the results at 87 octane.
Looking to lose some weight as well so I can be average. HeeHee.