Yamaha XS1000 vs. Kawasaki Kommander/Dasa 1000 - Observations

[Roo]

Both mine and Tru's ski's are done and have been on the water for some time now. I thought'd I would post my observations between the two setups plus thought others might enjoy the reading. All comments/questions welcome. I will for the most part keep this short and sweet. Before I go into more detail, here are the setups.

Roo's Yamaha setup:

Motor
Xscream 1000CC (90MM/78MM Stroke, 992CC) (~195 PSI Compression)
Full Spectrum 49MM carbs
Thrust billet airbox adaptors w/Yamaha stock airboxes
Boyseen intake system

Performance
Power Factor dry pipe
MSD Total Loss Ignition setup

Driveline
Skat Trak 145MM setback magnum pump (13/19 prop) (84.5 & 87MM reduction nozzles... more on that later)
Thrust Innovations Trim System

Hull
RRP Rickter FS-1 Fiberglass hull (113 lbs w/hood)
Worx WR228 intake grate


Tru's Kawasaki setup:

Motor
Kommander/Dasa 1000CC (89MM/78MM Stroke, 970CC) (~170 PSI Compression)
Kommander/Dasa Spacer Plate between cases/jugs
Full Spectrum 49MM carbs
Thrust billet airbox adaptors w/Yamaha stock airboxes
R&D intake manifold w/vForce3 reed system

Performance
Factory Pipe 800 SX-R Dry Pipe
Blowsion Programmable Ignition

Driveline
Skat Trak 145MM setback magnum pump (12/17 prop) (82.5MM reduction nozzle)
Thrust Innovations Trim System

Hull
Trinity Composites SXR Pro Hull (86 lbs w/hood)
R & D intake grate (max loader? / 3 shovels)




Both ski's are setup for freestyle ONLY. We don't race, top end is of no interest to us.

The first time we had them both out, the Yamaha had a 84.5 reduction nozzle. The Yamaha setup BLEW the Kawasaki setup on bottom end - it was no comparison. The Kawasaki came on very strong in the mid range, but still not quite as much as the Yamaha. Overall, the Yamaha felt stronger everywhere.

The second time, we were out at our buddies house where they were working on dialing in the Kawasaki a little bit better. At this point, I found no reason to mess with the Yamaha - it is a perfect package out of the box and I just want to RIDE. They were able to pick up a bit more bottom end power after tigthening up the Power Valves and some carb adjustments, but the Yamaha still blew it away on the bottom end (and all around for that matter). That same day, the Yamaha's steering nozzle shattered and reduction nozzle started to show some cracking. I switched it out to a 87MM reduction nozzle and a 91MM Pro-Tec Aluminum quick turn nozzle. I felt I lost bottom end power and picked up some mid, but the bottom end still killed the Kawasaki. I will going back to a 84.5MM once it is repaired (might step it up to a 85MM actually and call it good). Overall - Yamaha still blows the Kawasaki away.

Next route to go for the Kawasaki is a bigger reduction nozzle (84MMish), and open up the stinger end of the dry pipe. Also, a new ignition is going to be used. I will have more input in the next couple weeks once these changes are made. These changes without a doubt will make an improvement, but I can't see them creating the low end the Yamaha does.

Carbs came jetted/setup by our engine builder(s) for those wondering. I do not have the exact specs at this time.

-Andrew

 

[SXR-FOREVER]

Interesting read thanks. I noticed a huge difference in bottom end switching from the kawi 800 motor to a yamaha set up. One of the biggest changes other than the bottom end was gas life - Can you tell which of these motors sucks more gas?

Post up some pics of the skis PLEASE!!!

 

[5810]

Wow

 

[DAG]

suprized the much lighter hull did not make up for the slight difference in motor. Looking forwards to this threads progress as you dial them both in.

 

[Roo]

Interesting read thanks. I noticed a huge difference in bottom end switching from the kawi 800 motor to a yamaha set up. One of the biggest changes other than the bottom end was gas life - Can you tell which of these motors sucks more gas?

Post up some pics of the skis PLEASE!!!

The Yamaha has a cart kart tank, the Kawasaki has a stock tank. I generally go through two kart tanks to one stock tank - about the same for fuel consumption.

I will get the pictures from his camera tonight and post them up tomorrow when I am back at the office.

suprized the much lighter hull did not make up for the slight difference in motor.

Me to! I was honestly a bit worried that his might "feel" a little bit lighter. Couldn't be further from the truth - my ski still seems WAY more nimble and reacts quicker. To top it off, I have to drain over a gallon of water from my tray after everytime I ride (tray takes on water like a mofo).

 

[jetkid]

Thanks for the post Roo. I need to get out to the east side to do some riding with you guys soon.

How do the hulls compare? Does one turn better or ride better at a faster speed?

 

[Big Kahuna]

I would think the Kawi motor is being limited by the Dry Pipe. Probably could stand to run a Power Factor Pipe to open it up some.

 

[ATS_Aaron]

I would think the Kawi motor is being limited by the Dry Pipe. Probably could stand to run a Power Factor Pipe to open it up some.

Roo, I can loan you a Blowsion adapter plate if you want to try the Power Factor on the Kawi.

Aaron

 

[Scorn800]

Roo did you guys put a tach on either boat? I wonder how different the rpms are where each starts to pull hard. I'd also like to know top rpms just for the hell of it
The larger nozzle on the kawi should help bottom end.

 

[yamanube]

Interesting read thanks. I noticed a huge difference in bottom end switching from the kawi 800 motor to a yamaha set up. One of the biggest changes other than the bottom end was gas life - Can you tell which of these motors sucks more gas?

Post up some pics of the skis PLEASE!!!

I don't want to say I told yah so...

 

[Don 79 TA]

some good info
i'd say to get more pop out of that kawi setup to run the larger nozzles
i'm running 82/85 on her SXR and its got a nice pop to it, but for me, i'd want the larger ones

also hows the power curve compare on both setups? both smooth or aggressively snappy?
is that ignition on the kawi total loss style with an aluminum flywheel?
wonder what effects the wet pipe would have on that kawi setup or add some water injection (if possible to the dry pipe)
both motors looks awesome too

 

[ATS_Aaron]

The pipe difference could be huge.
There is a 25 psi compression difference.
and the whole nozzle thing that you are still chasing. Eric Malone runs Kawi pumps. Anyone know him well enough to get some recommendations on nozzle size?

Also, why does the Kawasaki need a spacer plate to run this billet cylinder. I'm not sure on DASA's mind set there and it makes me wonder if the port timing will ever be as optimal (for freestyle) as the Team Scream port timing on the Yamaha.

Aaron

 

[SuperJETT]

Very interesting. The larger wetted surface of the Kawi hull should be offset by the lighter weight but who knows.

 

[Roo]

Roo, I can loan you a Blowsion adapter plate if you want to try the Power Factor on the Kawi.

Aaron

Hey Aaron, appreciate the offer but I don't want to take the exhaust off my ski just to "test" on his... plus I doubt Tru wants to go through that.

Roo did you guys put a tach on either boat? I wonder how different the rpms are where each starts to pull hard. I'd also like to know top rpms just for the hell of it
The larger nozzle on the kawi should help bottom end.

They had one on Kawi - all I remember them saying is that it peaked at 7400 or something to that effect...

some good info
i'd say to get more pop out of that kawi setup to run the larger nozzles
i'm running 82/85 on her SXR and its got a nice pop to it, but for me, i'd want the larger ones

also hows the power curve compare on both setups? both smooth or aggressively snappy?
is that ignition on the kawi total loss style with an aluminum flywheel?
wonder what effects the wet pipe would have on that kawi setup or add some water injection (if possible to the dry pipe)
both motors looks awesome too

The stock kawi nozzle can only be safetly bored to 83MM (according to a couple sources). Looks like Tru sourced one and has a bigger one on the way (Sato Engineering). We'll see how that plays out, then maybe a new prop.

Both ski's are very smooth. The yamaha however is aggressively snappy no matter where you are in the powerband... I love it

The Kawi is using a stock flywheel (still a charging system). Blowsion/Kommander ignition that has a ton of different timing curves built into it. This however is being changed to an Advent I believe pretty quick per Kommander's recommendation. Tru does not want to jump on the Total Loss bandwagon quite yet.

Dry pipe is the way to go... adding water injection it would now be a wet pipe.

The pipe difference could be huge.
There is a 25 psi compression difference.
and the whole nozzle thing that you are still chasing. Eric Malone runs Kawi pumps. Anyone know him well enough to get some recommendations on nozzle size?

Also, why does the Kawasaki need a spacer plate to run this billet cylinder. I'm not sure on DASA's mind set there and it makes me wonder if the port timing will ever be as optimal (for freestyle) as the Team Scream port timing on the Yamaha.

Aaron

i don't know how much of a difference that pipe is making... his pipe is essentially the same as mine just shaped/routed differently (and he runs a waterbox... i do not).

true, there is a 25 psi difference which does help snappyness, but i can't see 25 psi making that RADICAL of a difference???

DASA does not make a Kawi cylinder for a stroker crank (least they didn't at the time they were putting this together).

 

[Roo]

Thanks for the post Roo. I need to get out to the east side to do some riding with you guys soon.

How do the hulls compare? Does one turn better or ride better at a faster speed?

come on man!

with the mag pump, the fs-1 is awesome no matter what speed. same for the sxr.

without a doubt the sxr corners/carves better, but the fs-1 is sweet for doing fast 360 spin outs. very squirrley if you want it to be.

I would think the Kawi motor is being limited by the Dry Pipe. Probably could stand to run a Power Factor Pipe to open it up some.

it might help a bit maybe... but his type is essentially the same as mine just shaped/routed differently. i can't convince him to make the switch because of the gas tank dilemma.

 

[DAG]

The Kawi is using a Kommander ignition that has a ton of different timing curves built into it. This however is being changed to an Advent I believe pretty quick per Kommander's recommendation

WAIT, Kommander is not even recommending his own ignition on his own setup?

i see a red flag?

 

[restosud]

water injection should help on the kawi.did wonders on the kawi 750 dry pipes.the 25psi will make for some of the difference in brap.

 

[McDog]

I wish someone would put a post like this up on one of the EME polaris motors.

 

[egbrig]

I am intrigued by the comparison but don't find this to be a true apple to apple test. There are too many variables between the two to call it a straight forward comparison but intrigued just the same. So could you argue dollar for dollar or part for part. The pipe difference, compression difference, nozzle, ignition (that’s huge) puts these two a distance apart, and you could argue ignition importance and pipe to intension. I do think it’s unfair to say one companies design is better based on such variances. What I’d like to see is upgrading the Kawi’s parts to match the Yami’s, then we’d have a comparison.

 

[Big Kahuna]

adding water injection it would now be a wet pipe.

Adding water injection will not turn a dry pipe into a wet pipe. It is just another way to tune the pipe. The water cuts off at a pre-determined RPM point.