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Main Area => General GS500 Discussion => Topic started by: DaxFX on July 03, 2007, 09:50:53 AM

Title: acceleration problems !!
Post by: DaxFX on July 03, 2007, 09:50:53 AM
hello to everyone ! i got my gs500e 1990 3 month ago .

i have a acceleration problem when its from 2rpm to 6rpm it seems that dont have enough power then when he pass the 7rpm BOOM it go way fast !!!!

not very good on english hoping you understan me !!
Title: Re: acceleration problems !!
Post by: coll0412 on July 03, 2007, 10:29:09 AM
I understand you. the GS 500 makes all of its power from 8K-10K RPMS so the closer you get to that the more pull the bike suddenly has, its pretty standard with high revving engines. Now get yourself a large displacement twin, and all the grunt is at a lower RPM, and some same at a more reasonable RPM.
Title: Re: acceleration problems !!
Post by: DaxFX on July 03, 2007, 10:35:14 AM
thanks for the info but i think i still have a problem !! its too much loose of power in low rpm . at the point the the bike seems to be shut off if i hit all the gas !! i got a yamaha 650xs special (twin) and i know that bike have super power on low rpm but my GS500 :( i make a race with the UM 250 and that bike is starting in the front untill my GS reach the 7rmp . and I dont want that my friends laught at me for that anymore....
Title: Re: acceleration problems !!
Post by: coll0412 on July 03, 2007, 10:37:53 AM
So what you are saying that when you are between 2K and 7K RPM and give if full throttle it stumbles?

Have you cleaned the carburetors lately or re-jetted it? I ask because it sounds like you have a fuel delivery issue and may require some carb cleaning. Have you pulled either spark plug to see what color(colour) they are?
Title: Re: acceleration problems !!
Post by: DaxFX on July 03, 2007, 10:47:27 AM
the spark are new but the cardurator i have not check ! the bike was not used for about 2 years when i buy it.. i think is what you said about carbs... i will need to take it to a profecional since i am not good on carbs ! some friend of mine tells me that maybe is an electrical problem !! but i dont think so . !!
Title: Re: acceleration problems !!
Post by: Jay_wolf on July 03, 2007, 10:49:10 AM
Your pic looks like a early model so it wont be the electrical , sounds like u need to flush ur carbs or rebuild them
Title: Re: acceleration problems !!
Post by: Egaeus on July 03, 2007, 10:51:34 AM
I agree with coll, it sounds like it could be a partially blocked pilot jet.  Without draining the carburetor, take it completely out of the bike.  Be sure to hold the carburetor upright the entire time.  Drain the carburetor float bowls through a paper filter like you would use for coffee.  Set that aside to dry.  

While the carburetor is still upright, take the float bowls off.  Check them for rust, or other foreign matter.  Clean out any that you see.  If it is rust, and it probably will be, you will have to fix the fuel tank.

Now, turn the carburetor over and you should see two brass jets.  Take out the pilot jet.  That is the small jet that is in a hole.  Dry it off.  Look through it toward a bright light, such as the sun.  Make sure it is clear.  

If there is rust in the carburetor, it is coming from your fuel tank.  A temporary fix is to use a cellulose fuel filter (designed for carburetors, not fuel injection) to filter out all but the smallest rust particles.  However, the tank should be acid washed and coated to fix this somewhat permanently.  
Title: Re: acceleration problems !!
Post by: DaxFX on July 03, 2007, 11:02:54 AM
its from 1990 there is maby something inside the carbs . dust or rust. in the first week having the bike one carb have a little hole in the side (like a drain) and the bike start to drain all the gas trhu that lillte hole I use carb cleaner an stop the leak!!
Title: Re: acceleration problems !!
Post by: Egaeus on July 03, 2007, 11:08:34 AM
Honestly, what you need is a thorough carb cleaning, but I don't have time to go through that.  I'm sure it's detailed somewhere.
Title: Re: acceleration problems !!
Post by: DaxFX on July 03, 2007, 11:10:48 AM
ok thanks a lot for the info that confirm what i think was the problem !! dont worry in explaining to me how to do it since i am not doing it myself, i will take the bike to a profesional ...

thanks a lot friends !!
Title: Re: acceleration problems !!
Post by: Wrecent_Wryder on July 03, 2007, 02:48:32 PM
Quote from: Jay_wolf on July 03, 2007, 10:49:10 AM
Your pic looks like a early model so it wont be the electrical...

I don't understand that at all...

:dunno_white:
Title: Re: acceleration problems !!
Post by: Jay_wolf on July 03, 2007, 02:52:37 PM
good point , no model is fuel injected . i suppose weak spark... .. I retract my Statement  :thumb: