I got a shorty moto gp exhaust for my 93 f2, i know i have to rejet it, what size should i go with? everything else is stock. Or at least give me an idea what to start at. Thank you

 

Any changes to headers or air box/filter? You might not need to rejet at all... go ride it first. Compare WoT on cold engine vs WoT on a hot engine. Note flat spots on your RPMs on the hot or cold engine.

 

everything is stock, even headers and intake, i changed the plugs, got rid of the back firing and made it way easier to start, so it might be alright but its winter so i cant ride it and put a load on the engine right now

 

I wouldn't change anything. Slip ons make the smallest air flow change of any mod.

And don't ever be hell bent on annihilating all signs of backfiring on deceleration. I did that once and had to run my bike so rich it was retarded. I have the best tuning I've ever had atm, very close to lean, lots of backfiring but tons of power, and very clean spark plugs with 0 sign of over heating or any other problems.

 

haha well alright, i always figured excessive backfiring was a sign of running rich, but thanks though.

 

Nah. Backfire is the combustion of the gases inside your pipe. You can not have combustion with out oxygen. A rich mix will leave you with left over fuel and no air. A lean mix leaves you with plenty of air, and enough combustible gasses in your exhaust to backfire.

Too rich may cause black specs of fuel to spittle out of your exhaust, but it will not backfire because there is no oxygen left in your air/fuel mix to ignite it.

 

I have a question.
Im putting GP style slipon on my F2.
Also, I ordered a K&N air filter.
Will I have to make changes to my Jets???
I gathered info on DynoJets KIT stage 1.. well, its quite expensive, so, I Would love to rather spend that money on tires or paint.
Is there any other options?