94 sp hard to start when warm

[ryan a]

My 94 sp has new motor and it is very hard to start when warm. I have read some tech articles and they say to replace new needles and seats. Is this what i need to do, if so what are the part numbers i need and can i do this myself?

[Bill O'Neal2]

Re: 94 sp hard to start when warm

270 500 126 Needle Valve.

[frankey01]

Re: 94 sp hard to start when warm

Also make sure you check your carbs pop off and make sure you are not too high

[Bill O'Neal2]

Re: 94 sp hard to start when warm

Why would the pop off pressure be too high ?
He wants to check pop off to see if the needles and seats will hold pressure so it is easier to start when it is hot.

[frankey01]

Re: 94 sp hard to start when warm

Because when I checked the pop off on one of my skis I was high and having the same problem and when I lowered it it resolved it.

[Danny Roszell]

Re: 94 sp hard to start when warm

If he uses the stock springs and simply changes the needle valve the pop off will not change. Even bending the arm will only adjust the pop-off within 1 psi.

Ryan A.

Just make sure the top of the spring fits into the control arm "nub" and that the control arm is flush with the metering body. If you have a pop-off guage perform a leak down test on the original needle and seat.

[Danny Roszell]

Re: 94 sp hard to start when warm

Ryan,

Do a search on the web for Mikuni and print out a copy of the mikuni manual for you carb. It is the best way to learn about these carbs and working on them.