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Main Area => General GS500 Discussion => Topic started by: CirclesCenter on July 25, 2006, 08:29:41 PM

Title: Why does my bike hate me? (Misfire)
Post by: CirclesCenter on July 25, 2006, 08:29:41 PM
Alrighty ladies and gents.

Bike is misfiring, and to make our problem more entertaining, it seems to be intermittent.

I have tried both PRIme and ON. No difference noticed.

Only does it under load.

I put 91 octane in every time.

HELP!!!!!!
Title: Re: Why does my bike hate me? (Misfire)
Post by: annguyen1981 on July 25, 2006, 08:31:12 PM
Unless you've got performance mods, only use 87 octane.  Why spend extra $$$ for nothing?
Title: Re: Why does my bike hate me? (Misfire)
Post by: CirclesCenter on July 25, 2006, 08:36:38 PM
To try to avoid this.
Title: Re: Why does my bike hate me? (Misfire)
Post by: annguyen1981 on July 25, 2006, 08:56:26 PM
Quote from: CirclesCenter on July 25, 2006, 08:36:38 PM
To try to avoid this.

Avoid what?
Title: Re: Why does my bike hate me? (Misfire)
Post by: CirclesCenter on July 25, 2006, 09:16:40 PM
Having any problems, hoping that even if I do end up with not so great gas (might be the problem?) at least it's the best gas they had at that station.
Title: Re: Why does my bike hate me? (Misfire)
Post by: annguyen1981 on July 25, 2006, 09:31:25 PM
Depending on the engine, sometimes getting the higher octane fuel does slight harm to the engine.
Title: Re: Why does my bike hate me? (Misfire)
Post by: melloGS on July 25, 2006, 09:45:05 PM
i don't think 93 octane can hurt any engine...maybe 100+, but not 93...
Title: Re: Why does my bike hate me? (Misfire)
Post by: annguyen1981 on July 25, 2006, 09:49:11 PM
Sorry for the misconception...  When I meant bad for the engine, I really mean things like lowered gas mileage is possible, or slight knocking (maybe)
Title: Re: Why does my bike hate me? (Misfire)
Post by: Alphamazing on July 26, 2006, 12:24:31 AM
Quote from: annguyen1981 on July 25, 2006, 09:49:11 PM
Sorry for the misconception...  When I meant bad for the engine, I really mean things like lowered gas mileage is possible, or slight knocking (maybe)

Knock is caused by too low of an octane gas. The gas pre-detonates or pre-ignites in the engine due to either pressure or heat or a combination there of, thus causing a knocking sensation. It also has to do with flame travel and interference, but I won't go into that. Higher octane gas prevents all this.

Here's a good picture:
(http://www.thor-racing.co.uk/images/what_is_detonation.jpg)
Title: Re: Why does my bike hate me? (Misfire)
Post by: Yankee Punker on July 26, 2006, 01:01:07 AM
 What year is your bike?  How many miles?

  When was the last time you've..... 
   
    Checked your valves clearance?
    Cleaned your carbs?
    Checked your throttle cable/carb sync.?
    Checked your spark plugs?
    Hows your voltage when running, and off?

  Just some suggestions.  And 91 octane is overkill, the GS does not have that high of compression for 91, it doesn't hurt it, but is just wasted money. I switch between reg. and mid-grade about every 150 miles, so I'm probably running about 88.
Title: Re: Why does my bike hate me? (Misfire)
Post by: deathlucky on July 26, 2006, 01:01:53 AM
wtf i use 95 octane because it is the cheapest
Title: Re: Why does my bike hate me? (Misfire)
Post by: Yankee Punker on July 26, 2006, 01:08:46 AM
Quote from: deathlucky on July 26, 2006, 01:01:53 AM
wtf i use 95 octane because it is the cheapest

What's the octane level of the most expensive?

And what's the compression ratio of your auto's there in Australia?
Title: Re: Why does my bike hate me? (Misfire)
Post by: deathlucky on July 26, 2006, 01:11:55 AM
lowest is 91 or 92 highest i have seen is 98
Title: Re: Why does my bike hate me? (Misfire)
Post by: Alphamazing on July 26, 2006, 03:01:53 AM
Quote from: Yankee Punker on July 26, 2006, 01:08:46 AM
Quote from: deathlucky on July 26, 2006, 01:01:53 AM
wtf i use 95 octane because it is the cheapest

What's the octane level of the most expensive?

And what's the compression ratio of your auto's there in Australia?

They have a different method for measuring octane than we do, same as Europeans.

Wacky foreigners!  :laugh:
Title: Re: Why does my bike hate me? (Misfire)
Post by: The Buddha on July 26, 2006, 07:15:06 AM
If it wasn't doing it before and ... You did any new mods ??? or any thing at all ... that's what fooked it up.
If you didn't do any mods or maintenenace - OK that's your problem ... it needs maintenance - airfilter, jetting, water in fuel, bad electrical connections ... whatever ...
Now if all that is good, and you're still having this ... Toss the damn NGK spark plugs out and put in champions. Serious.
Cool.
Srinath.
Title: Re: Why does my bike hate me? (Misfire)
Post by: NiceGuysFinishLast on July 26, 2006, 07:22:55 AM
It hates you cuz you dropped it. Duh.
Title: Re: Why does my bike hate me? (Misfire)
Post by: natedawg120 on July 26, 2006, 11:39:52 AM
Quote from: seshadri_srinath on July 26, 2006, 07:15:06 AM
If it wasn't doing it before and ... You did any new mods ??? or any thing at all ... that's what fooked it up.
If you didn't do any mods or maintenenace - OK that's your problem ... it needs maintenance - airfilter, jetting, water in fuel, bad electrical connections ... whatever ...
Now if all that is good, and you're still having this ... Toss the damn NGK spark plugs out and put in champions. Serious.
Cool.
Srinath.


thats it.  Change electrical compontents in order or cost starting with the plugs, then wires.  Also check the coils to make sure they have a good connection and theres no corrosion in there. 
Title: Re: Why does my bike hate me? (Misfire)
Post by: ignoreance on July 26, 2006, 02:14:43 PM
List stuff done to bike????
Title: Re: Why does my bike hate me? (Misfire)
Post by: CirclesCenter on July 26, 2006, 04:31:42 PM
Only the forks have been porked around with, the engine (to my knowledge) is stock.

Pulling plugs after I lay down for a bit, I'm so beat......
Title: Re: Why does my bike hate me? (Misfire)
Post by: ignoreance on July 26, 2006, 04:53:09 PM
And the bike I'm guessing is new...  Don't know
Title: Re: Why does my bike hate me? (Misfire)
Post by: CirclesCenter on July 26, 2006, 05:04:11 PM
1990.

So kind of more than a little not new.
Title: Re: Why does my bike hate me? (Misfire)
Post by: ignoreance on July 26, 2006, 06:10:22 PM
Mileage??  When does it happen under acceleration??? Deceiration  RPM range?  Last tune up?? have you gone to Counceling for this problem... Oh wait This isn't AA sorry... more info you can give the more it helps