Horsepower rating for GS550E

[headsbikesmopars]

My brother gave me a 1980 GS550E in decent shape that needs to be freshened up. It has a little over 25,000 miles on the odometer. Does anyone know the factory horsepower rating for the early 8 valve GS550's ? Do these bikes make a decent commuter, and are they easy on gas. Will they top out around 100 mph ? Need a good solid commuter that can be ridden out on the freeway at freeway speeds. Thanks for any input.
Terry

[oldschoolorange]

they were around 50-55 hp stock, mine will do about 110 mph , are not too bad on gas and are good on the highway.

[Calvin Blackmore]

hmm thought they were 65 HP at the crank
hmm where is my calculator

[Suzuki_Don]

I think you will find the two valve models were rated at 48hp.

[srsupertrap]

Motorcycle Classics: Under the Radar

I think you will find the two valve models were rated at 48hp.

Agreed, Motorcyle Classics magazine runs a Best bets on tomorrow's classics column. In the May/June 2008 edition they review the first generation Suzuki GS550 (1977-1977) and they published the Claimed Power: 49hp @ 9,000rpm.

[Nessism]

550 is a fine commuter vehicle. Enough power to keep up with traffic as long as you are not squeemish about letting the engine rev - 6000+rpm. Quite durable, like most GS bikes - members here report 100k miles on well cared for bikes.

[bryan]

I'll think you'll find the 550 a perfectly suitable commuter bike. I put a smaller rear sprocket on my to lower the rpms at higher speeds because I did a lot of highway riding. You lose a bit in acceleration, of course.

Just need to get my 550 running again. Great little bike, and my first one.

[brand new bike zealot]

My 78 550 gets about 6 liters per hundred k in the city (sorry about the crazy metric lingo) which is a hell of a lot better than 24 in my pickup... Great commuter bike, easy on gas and I've cranked mine up to 150 (again, in metric. just shy 100 mph) just to see where 4th redlined... Got a little scared.... Like another poster said, you gotta be comfortable revving up around 6-7 grand on the highway tho. Get it on the road!

[zig06]

My 78 550 gets about 6 liters per hundred k in the city (sorry about the crazy metric lingo) which is a hell of a lot better than 24 in my pickup... Great commuter bike, easy on gas and I've cranked mine up to 150 (again, in metric. just shy 100 mph) just to see where 4th redlined... Got a little scared.... Like another poster said, you gotta be comfortable revving up around 6-7 grand on the highway tho. Get it on the road!

Hmmmm

6L/100K....

6L = 1.585 US gallons.

100K = 62.137 US miles

that's 1.585 gallons per 62.137 miles

divide both sides by 1.585 (to get to 1 gallon)

1 US gallon per 39.2 US miles

(re-write to "normal" US english)

Your bike gets 39.2 mpg.

That's awesome!, I did this with out getting a headache!!

[Scotts]

Hey, I just got to figure my mileage. Same as yours. Mine is 86 550 es.

Scott

[Lynn]

mileage

Not being critical, but I would have expected better mileage. Back in the day I had a Honda 550 four and averaged around 45 mpg.

My "new" 82 GS1100EZ just got 45 on the last tank. That was the first I had checked mileage since working out all the bugs. Bike had 2600 on it when I got it in late March, and has 3200 as of this evening. That included about 40 miles of two up riding, but the rest solo. I haven't been riding hard, but do use about 3/4 throttle when passing.

I guess I just expected that a half liter GS would get much better mileage than the 1.1.

Lynn

[onchiman]

I commute every day on a 1979 GS550E (when it's not snowing of course). It's a very capable commuter. Quick, nimble and smooth. Mine gets around 47 miles per gallon, however, this is at speeds not in excess of 55 mph. I don't have freeways or highways to deal with here. Mostly rural roads with little traffic. I think that fuel economy is greatly affected by speed. With these bikes especially, the faster you travel, the more fuel you burn. That said I agree with the previous post about sprocket changing. There are options for swapping different sprockets based on your driving needs. If you do the freeways at high speeds, a sprocket change can lower the rpms and at least theoretically provide better economy. But I think wind resistance comes into play more at higher speed too which can also put a drag on efficiency, so to speak. The real payoff with the 550 is it's maneuverability in traffic. Properly tuned and maintained I think you'll be pleased with it.

[RWhitehouse]

That's all for mileage? I suspected it would be at least 50. My 450 semi-auto with only two gears does consistently 52-55mpg. To do 70 on the freeway it's turning like 6500RPM as well. Think that 450 is rated at like 23hp or something.

[cloudbreakmd]

http://www.motorcycleclassics.com/2008-05-01/Under-The-Radar/1978-1979-Suzuki-GS550.aspx

[zig06]

I commute every day on a 1979 GS550E (when it's not snowing of course). It's a very capable commuter. Quick, nimble and smooth. Mine gets around 47 miles per gallon, however, this is at speeds not in excess of 55 mph. I don't have freeways or highways to deal with here. Mostly rural roads with little traffic. I think that fuel economy is greatly affected by speed. With these bikes especially, the faster you travel, the more fuel you burn. That said I agree with the previous post about sprocket changing. There are options for swapping different sprockets based on your driving needs. If you do the freeways at high speeds, a sprocket change can lower the rpms and at least theoretically provide better economy. But I think wind resistance comes into play more at higher speed too which can also put a drag on efficiency, so to speak. The real payoff with the 550 is it's maneuverability in traffic. Properly tuned and maintained I think you'll be pleased with it.

Yup, my '86 550es got a pretty predictable 47mpg. That's average riding, to work and back again, and playing around on the weekends.

Did a ton of mods over the winter and have yet to ride it this year. When it's all said and done I'll report back.