Compression ratios;

2009 Ninja 6R 13.3 to one

2009 R6 13.1 to one

'09 GSX-R1000 12.8 to one

2010 Ford Focus 10.0 to one (base I4)

2009 Camry 9.8 to one (base I4)

2009 HD XL1200 9.7 to one

All VTR1000F 9.4 to one

1985 Yugo 9.0 to one

If you tell me your Super Hawk runs stronger on premium, I'll take you at your word.

But a high compression engine? Maybe not.

 

Ok, I'm not going to argue your point here... Because the VTR is NOT a high comp engine... But the "basic I4 engine's" you are compairing to are all FI engine's with adjustable spark and a whole lot of other trickery... They can run just as well on 87/93 and kitchen grease for all the compression matters... So comparing it to them is like comparing apples and elephants... It's not even oranges...

 

Good points, Tweety. For the record, I wasn't trying to compare apples to elephants, just pointing out the VTR doesn't qualify as high compression in 2009.

Of course, compression isn't the whole story. That FUEL INJECTED HD XL1200 (9.7 to one) calls for premium while the recommended fuel for the CARB VTR is 87 (U.S.).

My '83 VF750F (10.5 to one) feels a bit stronger and I can document gets better MPG on premium. I can't tell any difference on my VTR.

 

I don't know about you guys, but the best mileage I EVER got was all stock. Every little modification (baffelectomy, jetting, air filter) just hurt things. That's why I'm going back to stock. I got 45mpg all the time, no matter how hard or gentle I ran.

I run regular too, after pissing away my money on premium for this, I just alternate every now and then. I do run premium at the track, but more so if anyone needs some extra fuel I can help out

 

Probably true in most cases... I did get about equal mileage on my bike as it was bafflectomised and jetted though... A bit more omph, and same consumption is to me a win-win situation... Could probably have gotten more omph out of it if a sacrificed mileage though...

 

we went through this in another thread. Leave it there. My opinion is there as well. I won't even repeat it here as I think you are all stupid for arguing about octane rating when it comes to the hawk. Let's talk about fuel mileage...

If you want to improve the fuel mileage on the hawk, to any drastic measure, reduce the amount of air entering the engine. Smaller carbs will do this quite well. You could also chance the cams to less overlap and time them to maximize torque. A full fairing will help, too. And always remain in full tuck with an aero hump leather jacket. Or you could just realize that you bought a bike with huge carburetors that gets mediocre mileage when compared to small bore singles and twins that won't break 100mph which you should have got instead because you are merely experiencing some life crisis which a motorcycle will never cure. Good luck with the mileage!

 

There was a reason why you purchased a 1000cc bike right? If your only focus is fuel economy buy a 250.

In my opinion any vehicle that is all stock is bad! Customizing is about individualizing......personality is good.

Many of us ride because we love to ride, good fuel economy just happens to be a bonus!

 

So are you basically telling him his question doesn't merit an answer? I thought this was a technical section.

Stay tucked, stay under 75, and run regular, and you'll get the most miles per dollar.
Personally I think saving gas is a waste, but I don't think its my place to tell you what to think!

 

Best economy I ever got was 21km/L (59mpgUK, 49.4mpgUS)
That was with stock headers, my own cans, DNA airfilter and dynojet kit, running on '91.
We were two up, loaded with saddlebags and topbox.
She ran out of fuel at 360km exactly.
That was riding from Christchurch at a sedate and steady 100-110km/hr, with a 30km/hr tailwind as far as Ashburton. No wind at all after that, until Palmerston, where we picked up a mild headwind.
Christchurch to Dunedin on one tank...

And in the exercise, used up all my pure dumb luck for that year('08).
She ran out of fuel at the top of the northern motorway into Dunedin.
I rolled her down the hill and into the BP station at the bottom.

This really upset my father, who has an Aprilia Pegaso Strada, 650cc injected single. He was lucky to get 45mpg(UK) out of it, while I was averaging around 55 on my VTR. Eventually after a long argument with the place he bought it off (they promised 60mpg(UK)) they paid for a power commander and tuning. It now, just, turns 60mpg(UK)...

 

I got between 37 and 52mpg on the SH on my trip from San Jose, CA to Austin, TX. I was averaging about 45mpg.

 

My son and wife now share ownership of a 2006 Honda Shadow Aero. After a thorough inspection my son and I did a 900 km (558 miles) trip together. We took it slow as he just completed his MSF course a week earlier. We had a wicked quartering headwind on the outbound leg but were cruising at 55-60 mph. On the return, the winds were calm but cruising speed was 60-67 mph as his confidence grew. On both legs the S'Hawk got just over 50 mpg (imperial) or 45 mpg (US). The Shadow was closer to 56 mpg (US).

The best recorded mpg before this trip was around 36. Others on this forum have said a gentle throttle hand returns much better numbers but (until now) I had my doubts. Even with this new knowledge my fuel mileage has returned to just south of sh*tty when I ride alone. It seems that the S'Hawk torque and poor will power are the biggest culprits in low mpg numbers. I'm so weak.

-D

 

so running 91 vs 87 doesn't matter?

 

nope, at least it doesn't on mine, but I like to run 93 cuz I get better backfires

 

 

 

When I ran a highway test couple of years ago, I found if I ran restrained and steady between 60-65 mph I got a bit better than 50mpg.

If you want to squeeze more than that out of your VTR, sell it, buy an eight or ten year old Ninja 250 and spend the left over cash on gasoline.

 

 

Doesn't seem to make much difference on fuel economy for me. A gentle throttle hand (as others have often stated) seems to net FAR more real world results. I just came back from a 200km (124 miles) trip with stop and go traffic and some spirited sprints on the highway for about half the trip and she ran out of gas as I pulled into my driveway. I thought she just stalled from low idle and hot engine but nope. She's dry. I'll take being 'lucky' over 'smart' any day. BTW she left with a heaping (slightly over full-no fast corners please) tank of premium.

On a side note, After filling up several times up at stations that sell blended fuels with ethanol, I am NOT impressed. These are not my preferred brands but we had little choice. The bike ran like CRAP the first time but (again) chalked it up to hot engine and thought perhaps there was crud in the gas. The last time my riding partners (son with a carbed Honda Shadow and buddy on an old Victory) both commented on their rough idles and low rpm stumble. I never paid that much attention to where I got my fuel before but I sure will in the future. Here is a blurb from one of the fuel company's websites that explained the benefits:

H*sky’s M*ther N*ture’s Fuel is a clean burning fuel made of 10 percent ethanol and 90 percent gasoline. An alcohol-based product, Husky’s ethanol is made primarily from feed wheat. Carbohydrate (starch) in the grain is converted to ethanol in a fermentation and distillation process.

When blended with gasoline, ethanol boosts engine performance and reduces tailpipe emissions. Depending on the vehicle’s age, owner’s driving habits, driving conditions and other factors, ethanol-blended gasoline can reduce carbon monoxide emissions up to 25 percent. Compared to conventional gasoline, M*ther N*ture’s Fuel can also reduce greenhouse gas emissions associated with the production, transportation and use of fuel in vehicles.

This sure sounds nice but, based on my experiences, no more of that sh*t will be fed into my machine if I have any choice. From now on my only alcohol will be in good ole Canadian Rye Whisky. My internal organs don't seem to be quite so fussy...from what I can recall...

Cheers
-Darcy

 

Tweety,

I realize this is an old thread, but... I think what he meant by "lower throttle = higher rpms" is that when you are at high RPMs you don't have to open the throttle as far to make the same power. IOW, if you are in your power band, you might only need 1/2 throttle to get X hp, whereas if you are at 3000 rpm, you might need full throttle to get X hp.