tuning think something is off?

[DAG]

everyone is saying that with my setup my ski should hit hard.. i have nothign to compare it to.. but with my set up this thing is deff not ripping my arms off...
and theres a very slight delay in throddle responce...

I'm running 93 octaine and only getting 155psi in each cylender?

not shure how my carbs are tuned or what jets are in the thing.. trying to get that info now from the previous owner. "Donn AKA couchhater"

does this sound like anything is wrong... i would know instently if i could just compare it to another SJ... :/ maby my jetting is off. ?????

 

[SkiDaddy]

Check the top water injection hole - mine was almost totally plugged w/carbon, causing a delay in power off idle. Also close off the middle & bottom screws & use only the top screw.

 

[Frosty]

yeah, you need to find out how it's currently all set up so you know where you're starting point it. however, my SJ is set up for 185psi/cylinder (ADA 35cc domes) and it hits pretty hard for a 701. Sounds like your compression might be on the low side...

 

[Waste Land]

I dunno but 155 doesnt seem to be the right PSI for a ski with a head. Even with the lowest domes possible I'm running 178 each. Unless the cyclinder is ported and the domes werent changed....my guess.....

 

[Matt_E]

The porting is most likely responsible for that.

 

[douglee25]

You def. need to up your compression to take advantage of the porting.

Doug

 

[Frosty]

yeah, I put 37cc domes on a ported cylinder and only got 150 psi... went to 33cc domes and got up to only 178 psi... yet my other ported cylinder (from Paul) has 35cc domes and gets 185 psi... porting really does effect it... more than I thought until this year.

Matt, it's the raising of the exhaust port that causes that symptom right?

 

[douglee25]

yeah, I put 37cc domes on a ported cylinder and only got 150 psi... went to 33cc domes and got up to only 178 psi... yet my other ported cylinder (from Paul) has 35cc domes and gets 185 psi... porting really does effect it... more than I thought until this year.

Matt, it's the raising of the exhaust port that causes that symptom right?

Yes, you are correct.

Doug

 

[Matt_E]

yeah, I put 37cc domes on a ported cylinder and only got 150 psi... went to 33cc domes and got up to only 178 psi... yet my other ported cylinder (from Paul) has 35cc domes and gets 185 psi... porting really does effect it... more than I thought until this year.

Matt, it's the raising of the exhaust port that causes that symptom right?

Raising, mostly. But widening the port does it as well.
Think about it...the compression is achieved by squishing the air above all ports (Exhaust port is the top port). If the port is higher, there will be less to compress.
If the port is wider, more air will escape on the upstroke.

 

[Frosty]

Cool, thanks Matt/Doug... That's what I thought, but I wanted to make sure I was rationalizing it correctly. :biggthumpup:

 

[Matt_E]

A worn topend, bad ring gap, and score marks will lower compression, too.

As will using the wrong adapter for the compression tester.

 

[Big Kahuna]

Doooh, I forgot you have Don's ski, Compression should be a little higher.........

also, If that ski still has a SOLAS Concord prop in there, that will give you a slight delay in power transfer when you first hit the gas......... I run the SKAT Freeride cause I dont like this feature of the SOLAS Props.

 

[Freestyleriverrat]

Find out what you have first. What carbs are you running, what jets, ect. Don't change anything unless you know where you are now. That will dictate where you need to go and what you need to spend $$ on. 2 strokes are twitchy motors that when done up right are awesome but when something is off on them is feels like crap and makes you want to do a major change when it really only needs proper adjustment.

 

[DAG]

Find out what you have first. What carbs are you running, what jets, ect. Don't change anything unless you know where you are now. That will dictate where you need to go and what you need to spend $$ on. 2 strokes are twitchy motors that when done up right are awesome but when something is off on them is feels like crap and makes you want to do a major change when it really only needs proper adjustment.

well i know i'm running 44's i'll hopefully find out the jets and other info soon, Donns working long hr's and hasent had a chance to reply. i keep getting short mesg from his wife.

Doooh, I forgot you have Don's ski, Compression should be a little higher.........

also, If that ski still has a SOLAS Concord prop in there, that will give you a slight delay in power transfer when you first hit the gas......... I run the SKAT Freeride cause I dont like this feature of the SOLAS Props.

i know the 13/17 cut back 3mm is deff not a solas.
he told me it was a custom prop from a friend in brazil?????
I have noticed that when in a tailstand it doesent even feel like water is going through the thing. I'll be punching the throddle ans its like its only sucking air.. maby a pich prob? or is that standerd w/o a front exhaust.??

What pich should i run with a SKAT Freeride?


thank for the info. is there anything ealts i can check to help bump my compression up? i wont to get all the power out of this thing before moving to a magoo 760cc.


thank you
-grif

 

[JensNonsens]

hey buddy....

ok, next time we will switch skis, but really I dont think your ski is to weak. It rips pretty hard from the look. I think you just got used to it already. We might go to myrtle on friday, so maybe you have time to ride tomorrow or thursday.....


see ya

 

[Matt_E]

well i know i'm running 44's i'll hopefully find out the jets and other info soon, Donns working long hr's and hasent had a chance to reply. i keep getting short mesg from his wife.





i know the 13/17 cut back 3mm is deff not a solas.
he told me it was a custom prop from a friend in brazil?????
I have noticed that when in a tailstand it doesent even feel like water is going through the thing. I'll be punching the throddle ans its like its only sucking air.. maby a pich prob? or is that standerd w/o a front exhaust.??

What pich should i run with a SKAT Freeride?


thank for the info. is there anything ealts i can check to help bump my compression up? i wont to get all the power out of this thing before moving to a magoo 760cc.


thank you
-grif

The only way to tell what prop you got is to take it out.
Your ski cavitating in a tailstand has nothing to do with your impeller. The exhaust is bubbling up into your intake.

 

[DAG]

The only way to tell what prop you got is to take it out.
Your ski cavitating in a tailstand has nothing to do with your impeller. The exhaust is bubbling up into your intake.

sigh... not a fan of the side exhaust

 

[SkiDaddy]

Doooh, I forgot you have Don's ski, Compression should be a little higher.........

also, If that ski still has a SOLAS Concord prop in there, that will give you a slight delay in power transfer when you first hit the gas......... I run the SKAT Freeride cause I dont like this feature of the SOLAS Props.

Can you expand on why there's a delay? And is it for all Solas props?

 

[DAG]

i'll get back with you guys on the detaled specs on my carb's jetting
and what size my 701 is bored to, and what kind of port i'm running...

Prob wont be in the next few days, hopefully this weekend i'll get a reply from Donn.