Improving gas mileage?

[Anonymous]

Folks,

What would you do to a 1982-vintage 450 to improve gas mileage?

Mine runs well, but I can only go about 90 to 95 miles on a full tank before I have to switch over to the reserve. It just seems like it should go a little farther. About 80% of my riding is on the freeway (45+ mph, very few stops).

Your thoughts?

Dave

P.S. I haven't checked anything - plugs, compression, etc. D.

 

[earlfor]

Could you give that to me in what you are getting in miles per gallon? I have no idea how much fuel you are using to go 90-95 miles.

Earl

 

[lukehan]

Tire Pressure

Tire Pressure

I have found one of the easiest things to check is tire pressure, if your tires are a little low it can have a pretty big effect on mileage. Also, use a pressure gauge, just kicking the tires or something like that will not cut it. Check your manual for proper pressures.

Luke

 

[Anonymous]

It's usually about 2.5 gallons to top up the tank, although I've used some (maybe 5 miles' worth) of the reserve by the time I do that. My rough guess is I'm getting about 30 to 35 mpg.

I don't have an operator's manual for the bike, so I'm not sure where to find the correct tire pressure. Is there anything like a car emission sticker that would have the proper pressure right on the bike?

I do have a Clymer repair manual. I'll see if it lists the pressure in there.

Thanks folks!

Dave

 

[mdole]

Around here freeway riding is about 80 or 85 and if I do much of it my gas mileage drops off.

Judging by my son's Vulcan 500 and the old Honda 400E we had I would think that you should be able to get 50 mpg or so.

I get low 40s on my GS750 but if I slow down and ride a tank at 55 it gets up to the high 40s.

 

[Anonymous]

My wife's 1980 Kawaski 440 twin would get about 50 MPG, but it needed to switch to reserve at 95-105 miles.

 

[earlfor]

Thats pretty dismal for a 450. My 1150 gets 38 mpg at a steady 70-75 mph and 41 at 60-65. Do you have the stock toothed countershaft and rear sprocket? Do you have the stock exhaust and airbox? Does the bike have an electronic ignition or is it points? If electronic ignition, is it adjustable?
Have you checked compression. As compression goes down due to wear, gas milage decreases also. The first thing I would check is the compression.
The next thing to check is valve clearances. After that, ignition system and last, carburation.

Earl

It's usually about 2.5 gallons to top up the tank, although I've used some (maybe 5 miles' worth) of the reserve by the time I do that. My rough guess is I'm getting about 30 to 35 mpg.

 

[Anonymous]

It's usually about 2.5 gallons to top up the tank, although I've used some (maybe 5 miles' worth) of the reserve by the time I do that. My rough guess is I'm getting about 30 to 35 mpg.

I don't have an operator's manual for the bike, so I'm not sure where to find the correct tire pressure. Is there anything like a car emission sticker that would have the proper pressure right on the bike?

I do have a Clymer repair manual. I'll see if it lists the pressure in there.

Thanks folks!

Dave

For tyre pressures try 28 front 32 rear solo,30 front 35 rear with pillion,
My 550 gets 40 mpg(Imperial) round town and 50-55 at a steady 70.Daft question (sorry) but do you use all the gears?

 

[Anonymous]

For tyre pressures try 28 front 32 rear solo,30 front 35 rear with pillion,
My 550 gets 40 mpg(Imperial) round town and 50-55 at a steady 70.Daft question (sorry) but do you use all the gears?

A fair question. Yes, I use all 7 gears. (Sometimes I don't make it all the way into second and hit neutral. (Grin) Not very often, though.) I confess I'm not at all familiar with the ideal shift points. I'm frequently shifting around 4000 rpm, just based on sound & feel, although I notice the engine spins at 5000 to cruise at 55 mph. Could I wait and shift at a higher rpm?

Dave

 

[Anonymous]

Thats pretty dismal for a 450. My 1150 gets 38 mpg at a steady 70-75 mph and 41 at 60-65. Do you have the stock toothed countershaft and rear sprocket? Do you have the stock exhaust and airbox? Does the bike have an electronic ignition or is it points? If electronic ignition, is it adjustable? Have you checked compression. As compression goes down due to wear, gas milage decreases also. The first thing I would check is the compression. The next thing to check is valve clearances. After that, ignition system and last, carburation.

Countershaft and sprocket - don't know, suspect stock.
Exhaust and airbox - pretty sure they're stock.
Electronic ignition - don't know.

Haven't checked compression - I don't have a gauge. (Dad had one and Mom wants me to get rid of his tools, so I may be able to use his. Otherwise I'll have to go get one.)

Thanks for the suggestions. I wasn't sure the carb was worth digging into yet. (Cleaning the carb seems to be a popular cure for a lot of woes.) Sounds like I have some other work to do first.

Dave

 

[Anonymous]

Okay, round 2 with the questions:

How much does the brand of gasoline you use affect your gas mileage? Is it noticeable?

Dave

 

[Detman101]

A fair question. Yes, I use all 7 gears.
Dave

8O 8O 8O

You have 7 gears?
Where can I get one of those transmissions?!?!?!?

:lol:
Dm of mD

 

[earlfor]

Changing brand of gas or octane rating makes zero difference to either the 750 or the 1150.

Earl

Okay, round 2 with the questions:

How much does the brand of gasoline you use affect your gas mileage? Is it noticeable?

Dave

 

[Anonymous]

A fair question. Yes, I use all 7 gears.
Dave

You have 7 gears?
Where can I get one of those transmissions?!?!?!?

:lol:
Dm of mD

It's easy - just don't lift your left foot quite so hard when shifting out of first. It's that "infinite" (or "infinitely small") gear that's so hard on gas mileage.

Dave

 

[Anonymous]

<Okay, round 2 with the questions:

How much does the brand of gasoline you use affect your gas mileage? Is it noticeable?

Dave>


The only time octane makes any difference, is in performance. The higher the octane, the slower it burns. The longer the burn, the more pressure can be made to push the piston, wich results in more power. Of course you need to have your timing set if you want higher octanes to be used properly.
I have to laugh when I see people at the pumps throwing Super Unleaded in their average cars. They're paying more for no gain what so ever...unless they re-timed their cars to run on Super...

(p.s. it takes more refining to make Regular Unleaded then it does to make Super Unleaded. Yet they charge you less for the Regular).

Jeff

 

[redliner1973]

<The only time octane makes any difference, is in performance. The higher the octane, the slower it burns. The longer the burn, the more pressure can be made to push the piston, wich results in more power. Jeff

Almost, but not quite: piston speed has all to do with power production. gas burns at the same speed regardless of how fast your going, the faster the piston goes, the less time the gas has to burn, in effect, it starts going out the exhaust the faster the engine goes. Timing advancement will overcome some of this, but not all. you can sometimes see this effect running a lawn mower at night, and watching the muffler actually glow at top engine RPM, and lessen when idling. If your above statement were true, everyone would be burning premium because 'longer burn would = more pressure which would inevitably = more power. More octane only comes into help when compression ratios are higher. Octane then is used only to 'resist' premature burning.

 

[DMPLATT]

For tyre pressures try 28 front 32 rear solo,30 front 35 rear with pillion

Now I've got a question about tire pressure. My manual says 28, but the tires I have say 40 psi. What should I use? They were both low and I just pumped them up to 38 - 40?

 

[Anonymous]

I have to laugh when I see people at the pumps throwing Super Unleaded in their average cars. They're paying more for no gain what so ever...unless they re-timed their cars to run on Super...

(p.s. it takes more refining to make Regular Unleaded then it does to make Super Unleaded. Yet they charge you less for the Regular).

I know the grade of gas has little to do with mileage as long as the engine runs well, no knocking or pinging. But I'm curious about brand. I'd been putting Kwik-Fill (local discount chain) regular in the bike until about two weeks ago, and that's where I was getting about 95 miles on a tank. Last week and again early this week I put Sunoco regular in it and got 110 miles on the same tank. That's about 2.5 gallons, so I'm up to about 44 mpg from 38.

Maybe my riding style's changed. I'm using 6th gear for pretty much everything now, where before I'd stay in 5th while in town where the speed limit is 30. I also have been taking the freeway to work more often since my favorite back road (which is still posted 55 but has more stops) is closed for construction.

Dave

 

[Nerobro]

Actually, he's right. Higher octane fuel burns slower. it's also more resistant to self ignition. it also has a lower energy content. (yes. 93 octane fuel has LESS energy than 87)

Unless you bike somehow has a knock sensor, your fuel economy will be unaffected by the fuel you run.

 

[redliner1973]

Not faster or slower.....
'The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting. "


"The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.

It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio. "

Taken from:
http://auto.howstuffworks.com/question90.htm