Rejetting Help!

[BigCdub80]

Just starting a 1981 GS550 rebuild. Removed the air box and added some decent pods. Wondering where to start with bigger jet?
I believe stock are #145, I have to believe the pods let significantly more air in. I realize there will be some trial and error but does anyone have thoughts on what I should try first? I was thinking maybe #160..
Main jets are easy enough to get and fairly inexpensive, I just dont want to have dozens of useless ones laying around..
Any input would be appreciated!!

[Rich82GS750TZ]

Welcome to the site.

According to the chart found on BikeCliff's Website, you're numbers are way off.
92.5 Mains Jets
40 Pilot jets

Though I have read of some finding incorrect info in the chart. I did not compile the data.

http://members.dslextreme.com/users/bikecliff/images/carbspec_float_height.html

Your Factory Service manual should list the factory jet sizes. You Can download a manual from BikeCliff's website if you don't have one.

Someone else can recommend jet sizes for you. I'd recommend, since you have it, putting the stock air box back on, but that's just me.

Please create a signature w/ your bike info in it, then you'll never forget to type it.

And, we like pictures.

[BigCdub80]

I was pulling numbers from the wrong memory.. current main jet for the mikuni is #122.5
Was wondering if I should go up in 10% incrimants or less/more. I. Sure there will be some trial and error just need a starting point.

[BigCdub80]

Ill get some more pics asap but Im traveling for work at the moment..

[billyhoyle]

How do the plugs look with your current main jet? Sounds like it might already be bigger than stock based on Rich's post above, so do some plug chops and use the plug readings to determine if you need to go up or down.