i am at 50 feet elevation
full yoshi exh 165/170 mains,25 pilots,3rd clip on needle 2 1/4 turns on right & 2 1/2 on left (fuel mixture)
on decel it backfires + loud pop when first hitting he gas (at idle in neutrel)
sometimes stalls
no other problems fast top to bottom
any suggestions
help!!!!!!!!!!!!!!!!!!!!!!!!!

 

anyone????

 

Are you using the stock needle? Try turning your mixture screws out a 1/4 turn each and see if it is any better. They should be 2 1/4 LEFT 2 1/2 RIGHT your post has it the other way around, that would'nt help either.

 

gytr needle from the jet kit
mixture screws were like you said i just wrote it down wrong

 

Good. If a 1/4 turn seems to be better go a little more till it's gone but not to far, you should'nt need to go past 3 turns.
Have you adjusted the valves lately? The intakes tend to tighten up and could make it harder getting your carbs. dialed in.

 

You shouldn't have the pop when you first hit the gas. Personaly, I'm not sure that you need the 25 pilots. You may have too much gas in the carbs coming off the pilot circuit, then when you flood the carbs with the mains it's too much. I am at 875 elevation and I didn't need 25's until I went with the Trinity 686 kit.

165/170 seems big too. Have you done a plug check??

When I was at Glamis (which is right at sea level) I have to re-jet.

This is my set up:

Trinity 686 11:1 piston, cam. no airbox lid, K&N filter
175 left / 180 right Mikuni jets & needles
25 pilot jets
Screws: 2-1/2 left / 2-3/4 right
both needles in 3rd. clip position

I was running 180/185's , 4th. clip positions, 2-3/4 left / 3 turns out in the right carb.

Usually the popping on deceleration is a sign of a lean condition. But not always. I would almost bet that if you put a brand new spark plug in your bike and went out and rode it for 10 minutes or so to make sure that it was warm then did a HIGH RPM run in 3rd. gear, then flip you kill switch (WHILE YOUR AT THE HIGH RPM) pull your clutch in and coast as close as you can back to your garage. ha ha

You can let the bike cool a little or put on some leather gloves and take your spark plug out and take a look at it. Now back to my bet. would almost bet you that it will be really BLACK from being too rich. I could be wrong, but please check that out. Do it as I described. And remember to look at the base ring and not the porcilan.

Good Luck.

GregV

 

Popping could also mean a vac. leak. Are you sure everything went back together good?

I have a question as well. When you guy say right or left carb...are you looking at the carbs from the back of the bike or facing it from the front?

Shane

 

The back.

 

i will run t for a while today & then check the plug + make some minor adjustments to the mixture screws
in or out i dont know
on the mixture screws in is less fuel & out is more right????
anyone

 

Out is more fuel.