Sxr limited dry pipe pro igni ignition curve

[Lebis]

Could you help me with your opinion regarding the correct jetting and ignition curve for Sxr 800 limited with factory dry pipe, TBM head with 29cc domes , dual Novis 48 maxflow, mag pump, proigni ignition..... (it is marked stock on the ignition, so I don't really know which curve is uploaded, presume stock )?
Current setup is 145 pivots , 132,5 mains, LSA 3/4, HSA 2,5.

Right now it almost feel like a turbo lag, no bottom to mid, but then there is an instant hit, but still the top rpm could be better. I would like to gain some bottom end and a more linear power band.

I have a hard time to explain but when riding on a very close course, I always have to hold some throttle because of the crazy brake effect of this ski. So when coming out of corners the acceleration is poor, but at the end of the straight line if you just accidentally blip the throttle the ski just skyrockets you out of the turn.

I have also tried to change the main jets to 137,5 but it seems that I have just obtain a hesitation at high rpm to wot.
My current curve is attached.Thank you

 

[kevbo]

All dry pipes make the power either on or off. Oversized carbs make it even more so. If you can't handle the beast then drop back down to stock class until you can.

 

[Harbor]

I don’t race or work on Kawi 800’s….

If you where running an MSD multi channel pro TL ignition system the ignition curve would look different.. at least on Yamaha it does..

Advance starts at 1000 RPM
Full advance @1500 RPM
Carry full advance until your desired start retard RPM.. say 5k
Then pull desired amount of timing out thru rev limit

JC look at his timing curve

Is that a reputable ignition system

 

[Lebis]

Hi,

Thanks for all the help and all the suggestions. We have a local lake that is only opened on Sundays, so for today I have try to use all the available suggestions and try t he curve posted above. As stated previously I run 100 octane (RON) pump gas (EU), so I have dropped down the advance to 30 degrees max.

Running 145p at 1 turn out and 137,5m at 1 1/4 turns out.
Today there was a much better throttle response and for the first time the ski was ridable in a very good was, there was no sudden acceleration when blipping the throttle before the buoy. Still think that there is a lot of improvement to be done on the low end and also I think that I should g o back to 135m to get that high rpms really going.

The ski has a dynafy 14-21 impeller and it is not on the edge.....It was a race ski and it has a whole package ...TBM grilled head, drop down domes, Tassinari reads, NOvi 48 carbs, dry pipe, dual cooling with 4 pissers, Mag pump with trim, Pro igni ignition, .......The ski as a package has everything for ripping, just the domes are to be safe for our best pump gas, because we don't really need for going that far =)

Still beginning to really like this ski and started to enjoy this beast so I want to really make the best of it.

Thanks for the curve, please comment the posted one and if I should try this one. Really have no experiences with kawis and Proigni ignitions, until now more a Yama guy =)

 

[waxhead]

Its a very mild curve you are running. I would emulate the wax v3 on that ski and you will be fine on pump fuel. It the timing up top that does the damage, when your dynamic compression is getting high

 

[kevbo]

Check your top speed rpm, make sure the timing is retarded enough at whatever its turning.

 

[Lebis]

Thank you for all the answers, but it is still a little unclear for me which curve should I try, because of course every is totally different and I really don't understand how this thing works, so I am not comfortable to make my own one out of all these options.... I have too many questions =) Some curves bump the advance straight up to 30 at 1500rpm and then hold it to 4500 (like the curve posted by JC-Superjet)....some are more linear like the Advent curve posted. What is the better choice for my setup? @waxhead could you be please more specific with your curve opinion. Thank you again !!!!

 

[Harbor]

Do JC’s curve on your next water test… it’s a more normal looking curve and will help eliminate the curve a source of issues….

 

[kevbo]

You can get away with more timing and compression if the carbs are set rich of peak power. You can still burn a piston with less timing and compression if the carbs are set a little lean of peak power. Freestyle guys never deal with long full throttle runs so their compression and timing setups have evolved to be a little hot. For best reliability, set the max timing at 28 from 2500-5000 and then dump it down to 15 at full speed. You may need to lower the pump load a little. The throttle response will always feel mushy with a very strong surge when the pipe starts working. Lower exhaust ports work better with pump gas compression and timing. They trade power for throttle response.

 

[waxhead]

a slowly rising curve will give you the same sort of power, it will slowly rise.
Here is the wax V3 curve

Zeeltronic Curves

If you clink on the link here you will be able to download the curves for your ski and cdi. If you have a curve you want uploaded then contact us through the contact page and we ill look to put it up here Note: these curves are free for personal use. not for commercial use. Curve Type...

www.waxracingproducts.com

 

[Lebis]

So which one should I use ?

 

[Harbor]

So which one should I use ?

None of those 3 !!!!!!!!

Use JC’s curve, reduce total timing to 28 like Kevbo suggested and water test the ski…

I had to use a known good curve once to isolate a drivability issue… with a known good curve installed I was able to see how the rest of the boats parts were working..

 

[Lebis]

Ok , so like posted below? Or should I also lower the timing at 1500 and at 8500 rpm? What about the rev limiter setting and Base advance? Is it OK ?

 

[Harbor]

Ok , so like posted below? Or should I also lower the timing at 1500 and at 8500 rpm? What about the rev limiter setting and Base advance? Is it OK ?

It doesn’t look like you can adjust the curve at the 1,000 rpm point…. Can only chose baseline advance…? If it were adjustable @1,000 rpm, I’d start the advance at 1.000 (12 deg) and be at 28 at 1,500…. But that doesn’t look possible

So that curve looks good… adjust and have the curve finishing @ 12 deg thru rev limit and beyond, set rev limit to 8k… no rise after rev limit…

The 7,500 rpm point and beyond 12 deg…

 

[Lebis]

Yes, it is possible to add another colum. Will also set the advance at the rev limiter to 12. Thank you! The jetting is now 145p, 137,5m ....thinking to lower the mains to 135.

 

[Harbor]

Yes, it is possible to add another colum. Will also set the advance at the rev limiter to 12. Thank you! The jetting is now 145p, 137,5m ....thinking to lower the mains to 135.

Oh ok…. Add another column at 1k…. 12 deg at 1k and 28 at 1500…

 

[Mentzel]

I was never able to get super rich low speed jetting to work in any Novis. 1/4 to half throttle always sucked.

Try 125 pilots and 150 main

 

[Lebis]

For the dual Novis 48 Maxiflow? All the jetting specs that I have found were reverse jetting

 

[Lebis]

Oh ok…. Add another column at 1k…. 12 deg at 1k and 28 at 1500…

Hi. Been runing this ignition curve now with 145p and 135m. I have found out that the reason for the strange trottle response was that the trottle cable was not hooked in the right spot on the trottle lever not alowing to open the butterflyes all the way and also stretching the trottle when the pole was all the way down
Anyway, now I am running 95 ron octane fuel with the above jetting and curve and the acceleration is way more linear, but at wot the aceleration and speed has decreased drasticaly. Now it reaches max speed of 48 mph. Heavent really measured the max rpm achieved, but you can notice that the peak rpms are way lower. What do you guys think? Is this beacause of the new curve or is this now a carb tunninh issue?