change in jets

[suzukibandit]

ok i have an 82 gs550m and it has a 4 to 1 pipe on it and stock jets. Im wondreing if i can go up one size in main and pilot jets with out hurting the bike. Just wondering if any one can help me out.

[chef1366]

Richening won't hurt a bike unless you go too far and foul plugs.
I'd keep the pilot jets the same but take out the idle mixture screws a turn or so.
On the main it's a jetting game. I'd start with four sizes up. The sizes go in 2.5 increments so EX. 100 to a 110.

[BassCliff]

Hi,
Are you using the stock airbox or do you have pod filters installed? What exhaust do you have on it? I have a copy of the V&H recommendations on my website. Use it as a guideline. You may have to "shim the needles" to take away any mid-range stumble. If you have pod filters then, like Mr. chef1366 says, 4 sizes up is a good place to start. If you still have the stock airbox you may not have to go that big. But you will still have to experiment a little and read your plugs. Read about the "plug chops" technique on my website. There are more tips and links to other carb tuning pages in the carb sections of my website.


Thank you for your indulgence,

BassCliff

[suzukibandit]

It has the stock air box and a four to 1 pipe of unknown make on it. Ithasthe stock jets in it but im wondering if i changethem up one size will it hurt my performance?

[BassCliff]

Hi,

Running too lean for too long will do things like burn holes in your pistons. The Canadian bikes were jetted a little richer than those in the States. Reading your plugs is the best way to tell if you have the right fuel/air mixtures.

Running lean can improve performance for a little while, until your motor melts. The proper fuel/air mixture is the most efficient overall.


Thank you for your indulgence,

BassCliff

[chef1366]

You will hurt your motor by running stock jets with a pipe that flows more air than stock.
I gave you good jet sizes to start with.