Super Jet SJ Idle's fine but wont rev properly

[Marker Motorsports]

OK after kind of giving up the ski for a little bit, im back to work. Same spot though, ski starts right up, idle great, wont rev properly. Won't go over about 10mph. Brand new spark plugs, trimmed the ignition wires back, rezip tied the plugs back on, all new start/stop switch wiring on the ski. Fuel is fresh, one way valve is good. One thing I did notice is new plugs are blackish after a 2min run. Service manual says electrical problem. I can't seem to get a hold of a cdi to test with. My guess is its the cdi or stator. I have really been leaning towards sending entire electrical unit to JSS for refurb and be done with it. Not sure they can refurb the cdi. Any other suggestions before I send out and drop 400-500$?
Also will a round nose 650 cdi work for testing purposes? Ive got a 701, b pipe, msd.

 

[KTM434]

Roundnose never had a 650 but you can use a 650 cdi on a 61x 701 and a 62t is similar but has 2 similar connectors... I cant remember if its 2 male bullet connectors or 2 females but if you modify that 1 wire it works fine. That being said it does sound like an electrical issue to me

 

[madofcars]

Did you solve it ? What was the issue, my ski has same problem...

 

[Dmart29]

Was this ever fixed?! Mine is doing this I need to know asap

 

[mthomps]

Try riding it without the hood on and also try new cdi. Worst case is you have a spare cdi

 

[Dmart29]

I changed out all components of the e box with my waveblaster and the problem persist. It’s almost like instantly hitting rev limiter once any throttle is applied.

 

[Collussus]

stator ?

 

[mthomps]

You should try riding it without the hood to rule out exhaust leak.

Have you inspected pump, impeller and driveshaft? Leak down tested motor?

Does the rpm bounce like a rev limiter or will it not rev up? Does it rev up to a high rpm at all? Will it rev up on trailer

 

[Dmart29]

You should try riding it without the hood to rule out exhaust leak.

Have you inspected pump, impeller and driveshaft? Leak down tested motor?

Does the rpm bounce like a rev limiter or will it not rev up? Does it rev up to a high rpm at all? Will it rev up on trailer

Pump impeller and drive shaft we’re just removed to install a tap for second cooling line along with exhaust manifold tapped everything was good in there.

I didn’t not do a leakdown test. I installed a thrust girdled Head, is it common to have leaks with non conventional bolts?

It bounces like it’s on a rev limiter set to 3500 rpm. In and out of the water is the same issue

 

[Dmart29]

New head pistons and cylinders are all that’s been installed this the rebuild, it ran great prior.

 

[mthomps]

Ride it without hood and do a leak down test, worst case you rule it out and have a leak down kit

 

[Yamadog27]

Had exactly the same issue this weekend, rebuilt the carbs, checked compression, nothing helped. Had a spare cdi, changed that out and it ran like a champ.

 

[Dmart29]

I’ve changed cdi with a running one out of my blaster same issue. Is it possible that the cdi in the blaster won’t work in the sj? It’s a modded 6m6 cdi I’m using in the sj for test. The 62t cdi that was in the sj has same symptoms

 

[mthomps]

6m6 and 61x cdi is the same except the 6m6 has lower rev limit, but that wouldn't make your ski top out at ten mph. You said its modded so the rev limited is probably raised.

The 62t cdi has one wire that has a different connector type (male/female). I cant remember which is which.

I have had skis seem wonderful on trailer and under load (in water with rider) barely plane out. I have also seen a motor barely run on trailer the air leak was so bad.

I highly suggest you leak down test your motor. Even if it's not the issue you should have a leak down kit. You need a guage, bike tire pump, steel plates for intake side and exhaust side, home depot rubber, carb base and exhaust gaskets to mark where to drill the plates, and some short bolts to squeeze the rubber between your intake and exhaust sides of the motor. I think they are m10 x 1.25.
...
And ride it without the hood

 

[mthomps]

I have also had a bad cdi AND a bad spare cdi. lve also had a bad stator mess with me. You get to a point where you have a spare ebox worth of poop sitting on the shelf.

Carb(s) inspected and rebuilt? Many many things to try
Good luck man. Hope u find it soon