Stock Superjet Altitude Adjustment

[Morpheus122]

Hey guy, I just purchased a clean 15' Superjet from Denver, CO to bring back to Missouri. (5,000MSL to ~500-800MSL)

I looked through the manual for altitude adjustments and nothing specific was mentioned.

I called the dealer and they said the stock jets should be with the owners manual but none were found. I called them back and they then said that they did not re-jet the carb. The service advisor said that they:

1) Installed finger adjusters to the mixture screws for tuning.
2) Changed the float arm/needle spring to a heavier spring to prevent it from "wearing out quickly".
3) That I don't need to change back to the factory spring, just reset the mixtures the factory turns out.

Does this sound correct? I don't have a great understanding of pop-off pressure. Is it ok to assume they are correct, that I can run it how it is by re-adjusting mixtures only.

I get the ski delivered on Friday and plan on checking the plugs, and recording the mixture settings they had adjusted to compensate for elevation.

If anyone could give me some advice for a starting point that would be great, I'm only back home for a few days and would love to get some riding time in before winter without having to wait on parts.

Thanks,

Dave

 

[Yami-Rider]

With it being that new, your have to drill out the needle screw cap/covers. You don't need to raise the pop-off pressure, that is already set really high from factory.
You will be able to get it dialed in, just by turning the screws

Ride it around with new plugs and do a plug chop.

 

[Morpheus122]

With it being that new, your have to drill out the needle screw cap/covers. You don't need to raise the pop-off pressure, that is already set really high from factory.
You will be able to get it dialed in, just by turning the screws

Ride it around with new plugs and do a plug chop.

As far as the caps go, I'm interested to see how they made finger adjusters out of the stock screws. Do I not need to worry about the dealer changing the spring?

Plug chop is a good idea as well,

Thanks

 

[Quinc]

 

[Morpheus122]

Thanks I saw that chart. Which lead to another question, how come the dealer did not re-jet for Denver altitude? Are mixture adjustments alone enough?

 

[Yami-Rider]

Oh the dealer changed the needles, jetworks makes replacement adjustable needles for the newer cap style carbs.

Ask what they set the pop-off too. Up around 50psi would be ideal for stock 38s.

 

[Morpheus122]

Oh the dealer changed the needles, jetworks makes replacement adjustable needles for the newer cap style carbs.

Ask what they set the pop-off too. Up around 50psi would be ideal for stock 38s.

What the dealer said was they changed the spring to heavier for longevity(no mention of pop-off) which didn't make sense to me. And they said they modified the needled, they didn't say if the replaced them with the easy-turns. I'm having a hard time imagining how they could modify a recessed needle.

 

[Yami-Rider]

Mmm, Longevity.. ya.. That doesn't make any sense lol.

I guess your have to wait and see what they did to the needles.

 

[Morpheus122]

So the owner sent me some pictures. It appears the mixture covers are still in place??? The plugs look a little wet/rich so it may be setup perfect when I get it back it MO altitude??

Should I pull the carbs and check the jets or just ride it?

 

[Yami-Rider]

I would just ride it and see how it runs and keep and eye on the plugs. Best to keep an eye on piston wash too, but it takes a few hours to get a good wash reading.