701 Tuning question...

[Watty]

I'm having a bit of a crack at tuning my ski at the moment, and it seems I have most of it pretty good.

I do the trolling test where I let the ski idle for about a minute, and then punch it. It doesn't hesitate, or load up, and hits pretty strong, so I think the low speed jet and adjuster are fine. I'm running at 1 turn out on stock 38's, which seems to be about right from the reading I've done, so the jet size seems to be on the money.

My question is more to do with the top end. I have a tach hooked up (a slow updating tiny tach) and I know what rpm's I should be pulling, but I'm a little scared to lean it out to try and get the rpm's up to what it should be.

Basically, if I'm running a bit lean, and I do a wot run for say 15 seconds to keep an eye on the rpms to check for a lean/rich condition, am I going to have mass engine failure? I'm just a bit paranoid, thats all.

I understand that if I'm super lean, failure is the likely outcome. With that being said, is there any signs I should look out for, apart from looking at the tach that would indicate that I am way too lean on the top end?

Any help would be great.

Cheers.

Leigh

 

[jetskiking]

Are you taking plug readings? Thats normally the best sighn of a lean condition.

 

[Frosty]

run WOT for a few seconds, then stop the ski... do not let it idle. Pull the plugs and look at them... too oily or dark - too rich. Too light colored and very dry - too lean. Go for a cardboard color.

 

[Watty]

Yeah, I have done a few plug chops, but the problem is that they don't seem to be coloring too well. After about 20 minutes, they do get some color (new plugs) but I want to know if I'm going to hurt it from doing a wot run for long enough to get a good reading with everything going bye bye!

 

[sflsurfrider]

never use new plugs for plug readings and start rich and work your way lean as not to fry your engine.

 

[Big Kahuna]

yeah, use old plugs........

 

[waxhead]

Do not do a plug chop
they are very crude way to tune your ski and by the time its got any colour it will have siezed
and the ski can not be loaded 100% of the time thats the thing with jetunits and when it comes unloaded and hit the limiter and cuts the spark it will give you a false reading anyway

if you are worried about leaning it then richen it
if the revs on the tacho go down then you are to rich
and you know its safe to lean it off

the tiny tach is fine
if you are pulling big rpm then the superjet will be bouncing around every where anyway you cant see a fast moving tacho

 

[waxhead]

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[Johnnyhaggest]

Rich 'n up your highs run WOT for a few seconds and look at your RPMS. They will go up or down right away, (you need a starting RPM)
you'll notice rite away, there is no need for a long WOT run.