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Main Area => General GS500 Discussion => Topic started by: jsyzdek on April 25, 2014, 01:38:07 PM

Title: Fuel Efficiency
Post by: jsyzdek on April 25, 2014, 01:38:07 PM
Hi all

I was looking for a thread about fuel efficiency, but couldn't find anything detailed. I just see people posting 50-60mpg, while I'm usually in the 35-43mpg range. I know that fuel efficiency depends on many many factors, so I'd like to see a more thorough discussion on that.

I ride mostly in San Francisco (in the city itself, including downtown with all the never ending red lights and stop signs every 100' etc). Most of my miles I make on rides that are 2-10mile long (short). Add some time to warm the bike up (so you use the gas, but make no miles).

I usually wear a heavy suit and backpack so it's over 200lbs of weight on it. Sometimes I take my wife with me (:whisper: she's 140lbs, but officially she weighs nothing ;) ). And when I ride, I ride hard. Probably not quite as hard as the bike possibly could, but I do go over 60-70mph whenever I can.

These things don't help the fuel efficiency, I know. But when I ride, I don't do it to save gas. I do it to have fun. However - if there are other people out there, who ride like me and still make 50mpg, then I'd like to know what I can do to save myself some $$$.

Thx for any replies!
Title: Re: Fuel Efficiency
Post by: gsJack on April 25, 2014, 02:08:29 PM
Here's some GS500 riders posting their gas mileages averaging 38-75 mpg, quite a range:

https://www.fuelly.com/motorcycle/suzuki/gs500

I average 60 mpg all summer long here in NE Ohio just riding around with a good deal of spirited riding. It can drop to 50-55 in the winter with more choke and shorter runs but it's only a small part of my yearly mileage. I have 100k miles on the 02 GS now and am still doing a strong 60 mpg average.

I did a little better on my 97 GS500E averaging 60-65 mpg for the 80k miles I put on it with a similar winter drop.

People who modify their GSs with jets, air filter, and exhaust changes get quite a bit less mpg for their efforts. My son rejetted my old GS and got more like 50 mpg commuting and then put in a used low milage engine with his old carbs and gets same 50 mpg.

The magazine testers usually report about the same 50 mpg or so, here is the data from all the published tests I've found on the GSs from 89 to present:

http://www.gs500.net/gallery/data/500/GS500tests.jpg
Title: Re: Fuel Efficiency
Post by: Suzuki Stevo on April 25, 2014, 02:14:56 PM
My average was 55-65, on one occasion I managed a tank at 69.8 Mpg (open road 85-90°, plus one pilots, mains and plus Juan CSS), useless Rpm is the main reason for bad Mpg  :dunno_black:
Title: Re: Fuel Efficiency
Post by: adidasguy on April 25, 2014, 02:29:32 PM
I average 50-60mpg.
I've seen a few people come over who complain about poor mileage. Then I see them let the bike sit warming up for 5 minutes. Way too long and will overheat the engine, making the headers cherry red at night.
10-30 seconds is more than adequate for warming up. Sit there for 5 minutes and all you do is waste gas.
For my bikes 4k-6k RPM is what they like. Start going over 7k and your mileage will drop. No need for RPM that high unless you need to gun her to pass a truck.
Keep idle around 1200-1500. Higher and all you do is waste gas.

Title: Re: Fuel Efficiency
Post by: robfriedenberger on April 25, 2014, 02:39:02 PM
I would hate to ride with Addiasguy (no offense) but I use the full rev range all day long haha you only live once and you gotta do what makes you happy! Usually I get 9-10 MPG In my truck so I'm happy with any MPG but even with leaving on it I wt a min of 35MPG up to 50MPG 


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Title: Re: Fuel Efficiency
Post by: jsyzdek on April 25, 2014, 03:22:38 PM
I don't know whether or not my engine has any custom parts in it. Previous owner bought it with a dry engine (without knowing it) and messed up the engine the first time he started it. Then he replaced the engine with a used one (from 2009) but he probably doesn't know its story (except for the mileage that's in my registration papers).

I hardly ever rev it up above 8k (usually 5-7k is my range), it idles at 1450rpm. And I warm it up for just as long as it takes me to go open the garage gate, put my helmet and gloves on, and put the helmet bag into my backpack. Probably 60-90s. If I warm it up less than 30-40s, it doesn't like it at all. Temps in SF are around 60F year round.

It sounds like I should be in 45-55mpg range with my riding style. Any hints on what to adjust?
Title: Re: Fuel Efficiency
Post by: Jimbob on April 25, 2014, 03:55:55 PM
I changed my air filter and put in iridium spark plugs from standards and started getting 30-50km's more per tank
Title: Re: Fuel Efficiency
Post by: Watevaman on April 25, 2014, 05:17:24 PM
 I've been averaging around 45-50 the past few fillups and these have been incredibly hard runs for a good chunk of them. Lots of full throttle, high rev shifting, etc.

I'll be able to tell you later, when I stick the 16T front sprocket back on and am doing more commuting than twisties, how much it goes up.
Title: Re: Fuel Efficiency
Post by: robfriedenberger on April 25, 2014, 05:19:04 PM
Your idle first off, set it to 1200 +-100, check your air filter, go though a tank if gas and check your plug color


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Title: Re: Fuel Efficiency
Post by: Big Rich on April 25, 2014, 05:38:16 PM
I'd say definitely go thru all the maintenance stuff first and foremost (carb sync, valve clearances, etc, etc). To see if it's your riding style or the bike, hop on the highway and ride for an hour at a steady (and not racing) speed. When you get off the highway, fill up your tank and see what you get.

On my GS450, I've gotten less than 40mpg recently. But that's old winter gas, warming up for ice cold starts, stop and go 10 minute rides, blah blah blah. If I go on any longer trips I get near 60mpg.
Title: Re: Fuel Efficiency
Post by: jsyzdek on April 25, 2014, 06:47:51 PM
Thx guys!

Maybe I should add here, that when I got the bike (and it is my first) it felt low on power, but I had no idea what to expect, so I just rolled with it. Until one day it just died. I thought it could be a number of things, but finally it appeared that there was about a gallon of water in the tank  :icon_rolleyes:. And because of high ethanol content in CA gas the water was easily dispersed in the gas. When I had it in a jug, it took it about 10min to fully separate into two layers. And the water layer was flammable from all Ethanol in it. After I got that figured out it was a totally different bike. Then I had enough torque to realize that the clutch was off....

I also suspect there are other things that need attention, just didn't know where to start. Do you think that high water content could've damaged anything? :dunno_black:

I'm kinda good with mechanical stuff (worked a lot with tractors and semi trucks), just never worked on a bike before (except for a few fixes I've done so far). I don't have a garage either, have to do everything in the street (I can't start a job that takes more than one afternoon), but I do have quite a selection of tools (because I never leave them on the street  :laugh: )
Title: Re: Fuel Efficiency
Post by: Meuryn on April 26, 2014, 12:28:52 PM
With a K&N lunchbox, rejet and aftermarket exhaust I consistently get 60mpg. It gets ridden hard all the time, half of the ride usually through the city, the other half on twisties. MPG never seems to change much either.
Title: Re: Fuel Efficiency
Post by: jsyzdek on April 26, 2014, 12:52:23 PM
I'm wondering whether or not the engine is running too reach. Given that there was a water-in-the-tank problem, maybe somebody has adjusted the mixture to compensate (without tracking down the actual problem)? Now when it's clean maybe that's what needs adjustment? How should I get around to do it?
Title: Re: Fuel Efficiency
Post by: robfriedenberger on April 26, 2014, 04:30:29 PM
The mixture screws are on the bottom of the carb, the factory plugs them with brass. So it will be easy to tell if some one drilled them out to mess with them!


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Title: Re: Fuel Efficiency
Post by: radodrill on April 26, 2014, 06:54:37 PM
Quote from: robfriedenberger on April 26, 2014, 04:30:29 PM
The mixture screws are on the bottom of the carb, the factory plugs them with brass. So it will be easy to tell if some one drilled them out to mess with them!

Only for US and California spec bikes; these plugs are not mandated elsewhere.  If the OP is in the UK or Australia this wouldn't apply.
Title: Re: Fuel Efficiency
Post by: robfriedenberger on April 28, 2014, 01:31:07 PM
The PO is in the US


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Title: Re: Fuel Efficiency
Post by: jsyzdek on April 30, 2014, 12:53:32 PM
yeah, the previous owner is in CA. Not sure where the replacement engine came from though. I'll be back home in a few days. I'll check the engine out.
Title: Re: Fuel Efficiency
Post by: jsyzdek on June 01, 2014, 08:42:37 PM
Hi guys

Just a little update. Took my bike on a 80 mile ride today. Some part of it through SF, then cruising along the coast, then about 50miles of twisties and another 8 miles of splitting lanes in heavy traffic. My fuel efficiency is up to 55mpg from the 36 I was used to. Seems like all is good with my bike. Good I didn't start tweaking anything too early...
Title: Re: Fuel Efficiency
Post by: Gorilla on June 02, 2014, 01:54:57 PM
work it!
Title: Re: Fuel Efficiency
Post by: twocool on June 03, 2014, 03:41:18 AM
80 miles is far too short of a sample to determine fuel efficiency.

Many errors in filling, wind, terrain, etc will skew the findings.  Mostly driving style is the #1 factor.

Fuel efficiency is only meaningful as an overall average of many tankfuls and many miles.

I've had individual tank full readings as high as 72 MPG, while others in the low 50's.......

But looking at the overall average over 40,000 miles, and how ever many tankfuls that is, my mileage seems to stay right about in the low 60's...

Go onto the 'fuelly" website for easy tracking of you mileage over longer sample time....also see what others are getting...look at those with many tankfuls for more realistic readings..

Cookie







Quote from: jsyzdek on June 01, 2014, 08:42:37 PM
Hi guys

Just a little update. Took my bike on a 80 mile ride today. Some part of it through SF, then cruising along the coast, then about 50miles of twisties and another 8 miles of splitting lanes in heavy traffic. My fuel efficiency is up to 55mpg from the 36 I was used to. Seems like all is good with my bike. Good I didn't start tweaking anything too early...