Fuel Usage – Part1

[The Stranger:Me]

First a little history.
Only started riding less than 12 months ago.
Had the mandatory 250 for a while but got my full via the Pass Rite cbta system and as soon as possible took the next logical step up in size. To a Honda Blackbird (1100cc).
Now the bike is awesome. Pulls like a freight train, excellent getting on the gas, smooth as silk, good pillion accommodation, and best of all it’s a Honda so you know it’s reliable.
1 small downside, the fuel usage after the 250 was quite, well surprising.

The 250 was new and as it loosened it got substantially better fuel economy from about 180km on the first tank to about 240km a tank after about 2,000 km.
The Blackbird had done 600k when I got it and I thought hey it will loosen and get better. It didn’t.
So at about 1,500km on the bird I did a fuel usage check. To try and ensure accuracy I did a few in a row and averaged these. The average was about 38mpg I then set about seeing how various factors would influence this.

First thing I tried was a K&N filter. After 3 consecutive tests with the K&N I was getting about 43mpg.
Now as well as improved economy there is an increase in power, most surprisingly torque in the lower revs is improved making the bike more “ridable”. I can’t notice any improvement at the top end but that may be more to do with the rider than any lack of improvement. A Dutch magazine claims they had a stock one of these from 0 to 100 in 2.4 seconds so you see I really would not know if that was 2.3 now or not.
What next?

Well I had been running it on 91 octane because the manual says I can. My SS actually runs better on 91 than 96 so why not use 91, it’s cheaper right?
Wrong!
Running it on 96 octane I now get 47mpg. As well as that there is a significant increase in low down torque, hill starts are easier and if I happen to be in a higher gear than I should going around a corner it really doesn’t matter. Again I can’t detect a change at the top end, I seriously doubt many people could detect a HP or 5 on a bike such as this without the benefit of a dyno.

I have a fairly typical commute so have been careful to only include results for commuting. Open road driving has seen a definite improvement, but I don’t consider that I have enough consecutive results to present a reliable picture here.

Despite petrol increases from 132.9 cents for the 91 at the start to 148.9 cents for 96 now the cost of fuel per km is down significantly and the bike is more responsive, more forgiving, more “ridable” and still goes like hell. The K&N should pay for itself ($132.00) in 10,000km, or less if fuel prices increase.

The SS now sports a K&N filter. I try and drive it as little as possible as it is quite boring after the Blackbird.
These things are famous for being very asthmatic. Orix racing take them from 225kw to over 300kw simply by fixing the breathing and computer.
There is an improvement in fuel economy (seat of the pants only) but also a definite improvement in power, as the rider of a silver firestorm may attest. It now spins both rear tires from a standing start on dry road, which it wouldn’t do previously.
All our fleet is going to K&N air filters now.

I have more ideas to try (anyone know how to remove catalytic converters) so watch out for part 2 in the not too distant future.

[Sniper]

Mate, going from a 250 to a 1000 will always shock you with fuel economy and there is very little you can do unless you want to push it

[ManDownUnder]

Interesting - I tried both 91 and 96 (and 98...) on the RF and there is bog all difference in mileage. Might change the air filter now that you mention it though...

[zadok]

Good write up. Interesting. I like to keep track of my fuel economy. I've only just got my bike and am going to keep an eye on what it does as well.
p.s only 6 months old even tho it is a 2003 model.

[kerryg]

First thing I tried was a K&N filter. After 3 consecutive tests with the K&N I was getting about 43mpg.

Nice bike those Blackbirds.

When you installed the K&N did you have to re-map or change the pipe?

[SARGE]

i use either Mobile 8000 or BP Ultimate in my FJ1200.. noticed a HUGE milage difference over the 91 shit ( used to do about 210 a tank.. now almost 300 on a normal commuter week)

[Pancakes]

How to remove a catylitic converter? 1) Be a mongrel and cut it out and weld some pipe in it's place. 2) Remove the Catylist, take it to an engineer/exhaust shop and get them to make a dummy with the same bolt plates on each end and a straight pipe in the middle, they should give you a copper gasket for eack end too. It'll look tidy enough for the WOF biddys and you can swap it back if you need too or sell the Catylist to cover the cost of having the pipe made. You might just break even and get better performance/efficiency at the same time.

[The Stranger:Me]

I didn't do anything to it other than just install the filter.
I do recall somewhere (ixxra site I think) indicating that these things are a bit rich anyway.

[Sniper]

How to remove a catylitic converter? 1) Be a mongrel and cut it out and weld some pipe in it's place.

Ow bee Rangi. Jus taek him out to da whanua's place and we do't fo a doz bro

[louisb]

Have you tried putting a little bit of acetone in the fuel. It seems you've got a good way of working out actual economy so it'd be a good test. the stuff isn't cheap (about $10 to 500mls). I put 20ml of acetone per 10 litres of fuel.

I've put it in the car and the bike. my vt 250 is going like a rocket now. the car, a 1990 bmw 320, is idleing much smoother and 'seems' to have more power.

there was a thread a couple of weeks ago http://www.kiwibiker.co.nz/forums/sh...hlight=acetone

[clint640]

I'd be pretty happy with 47 mpg out of an 1100, my 640 gets 50 - 55.

Cheers
Clint

[Morepower]

Fuel consumption ? yep the TL does that so I worked it out for you, from a race track worst of 17.8mpg to a crusing best of 37mpg. Usualy its probably in the high 20's when fanging around.

But then who cares ,its still better than the 12mpg my car does.

[Flyingpony]

How to remove a catylitic converter? 1) Be a mongrel and cut it out and weld some pipe in it's place. 2) Remove the Catylist, take it to an engineer/exhaust shop and get them to make a dummy with the same bolt plates on each end and a straight pipe in the middle, they should give you a copper gasket for eack end too. It'll look tidy enough for the WOF biddys and you can swap it back if you need too or sell the Catylist to cover the cost of having the pipe made. You might just break even and get better performance/efficiency at the same time.

Don't think having a catylitic or not is a WOF item.
My previous car had one, then I got it removed after it started to smell rotten.
Never had any comments at WOF time.
Made no difference on performance except that rotten smell was gone and in lower RPM there was a new rattle and a stronger exhaust growl only noticable from the drivers seat, not to other people outside.

[Lou Girardin]

I wouldn't remove the cat unless you're happy to fit a new one next year. The Gummint is talking about making them part of a WOF.