Joe and Chris Grace's seadoo spark powered Krash Footrocket

I think your comments would have been more valid without the 2 stroke dinosaur comment. The 4 stroke has a lot to prove in our arena, the 2 strokes have long proven history, and guys are still squeezing more and more power out of the setups today. I think its cool Chris is doing this, he is trail blazing for sure, but as mentioned, there is a lot of work ahead before the 4 stroke can prove itself as a freeride/freestyle motor.

Not hate, just stating where the sport is today.

I have no hate or ill will towards 2 strokes, I love them, I run them and when I progress far enough as a rider I will prob end up with a TPE 964.

All that being said, aqs far as the EPA and any governing agencies are concerned 2 strokes are exactly that, dinosaurs. I am lucky enough to live in an area where I have no restrictions on 2 strokes and can ride what I please. A lot of people are not so lucky and once a lake or body of water has a 2 stroke ban I fear it will never be reversed. in comes innovation and new tech.

I am in no way saying this id the best thing since sliced bread and begging everyone to throw away their 2 stroke skis and get a 4 stroke. I am just trying to put all the hard work Joe and Chris have put into this out there for all to see.

If you don't agree, don't like 4 strokes, or just don't care, then don't read any further into this thread and go about your normal business.

I want to support this sport and ANY AND ALL innovation that our fellow riders may come up with. I have another 30 years ahead of me in this sport and I love to see new and fresh ideas even if they don't pan out.
 
2 strokes are proven and aren't going anywhere. Tons of work to get the 4 stroke to get anywhere near the power of 2 strokes. And as I said before we by no means are trying to eliminate 2 strokes, just offer an alternative. I know it's different but Motocross has made the switch so maybe one day we can too!

See, perfectly civil. A conversation about these things can still be positive even if concerns for possible issues are being brought up. As mentioned, these things need to be able to handle inversions, water ingestion and a good hard buttwhipping in the freestyle world, and to date, I do not know of anyone who has managed to overcome these things in a standup with a 4 stroke motor. There are some legit concerns and issues that need to be addressed to make this this work well.

Everyone sitting around and agreeing and singing kumbaya from their keyboards with their positive tone without offering any legit input to solving the classic "4 stroke in a freestyle ski" concerns isnt going to help Chris make this thing run any better, as much as buzzard being negative is going to make it fail.

@chrisgrace , I am interested to see how you get this thing to run, I saw it in the water in Daytona, I heard it from way down the beach, it definitely attracted some attention. Keep us posted on your next surf ride, and of course, let us know when you get it upside down!
 
See, perfectly civil. A conversation about these things can still be positive even if concerns for possible issues are being brought up. As mentioned, these things need to be able to handle inversions, water ingestion and a good hard buttwhipping in the freestyle world, and to date, I do not know of anyone who has managed to overcome these things in a standup with a 4 stroke motor. There are some legit concerns and issues that need to be addressed to make this this work well.

Everyone sitting around and agreeing and singing kumbaya from their keyboards with their positive tone without offering any legit input to solving the classic "4 stroke in a freestyle ski" concerns isnt going to help Chris make this thing run any better, as much as buzzard being negative is going to make it fail.

@chrisgrace , I am interested to see how you get this thing to run, I saw it in the water in Daytona, I heard it from way down the beach, it definitely attracted some attention. Keep us posted on your next surf ride, and of course, let us know when you get it upside down!

Sorry if I ever came across as trying to push 2 strokes out, think this was going to replace 2 strokes in free ride or make this out to be anything more than a very cool project. I actually got a chance to ride the ski and my opinions are first hand. I am waiting for the green light to go out with Joe and Chris and really put this thing through its paces and report back actual firsthand factual info. I know how hard Joe worked for this and am just trying to be a supportive individual.

The test ride with the 60 touring mode showed real promise. The weight didn't seem to hurt, and seemed to help the way the ski rode and handled. more to come once we get it in the water with the new tune
 
Location
Ohio
FWIW I thought it was cool and clean and it was cool talking to you guys about in Daytona. Just have fun and keep up the great work! I would have liked to have ridden it but it wasn't starting when I was checking it out....
 
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I thought it was cool and appreciated how they used as many SeaDoo parts as possible and worked to minimize the amount of custom fabricated stuff to give this a future as a possible kit.
Fundamentally, two strokes should be capable of making twice the power per CC of a four stroke because they put power to the crank every time a piston goes down, not every other time. So maybe dirt bikes reach a point where they don't need more power, but we need ever bit we can get.
Regardless, though, I think this is cool and would think it should appeal to those west coast lake riders, at the least. And they stuffed it in a Foot Rocket! Could have done a Predator with a larger engine bay, but they made it as challenging as possible from the beginning. If this were mine, it would be the Foot Sprocket!
 
I think its a cool install , I like when people get creative with ideas and think outside the box , Great work imo . if not for guys like this there woud be a lot less aftermarket parts/hulls for sure. You never know it may lead someone else to make something else even better or different or similar.
 

Scorn800

Ride for life
Location
North NJ
I think it is awesome! It's so nice to see someone try something new. Great work!
I would really like to see Seadoo or kawasaki produce a new 4stroke or etec standup
 
a lot of the comments in here are the same comments that were in the dirtbike world in the early 2000's.... 4 strokes are for racing, they are too heavy, they will never take over freestyle. well 4 stroke 450's are now better than 2 stroke 250's in almost every way..... if we can get the same technology developement they did our skis will be all headed this way

saying that i wish we could get a 900 twin build out of 2 yzf450 engines..... so many rpms and power
 

yamanube

This Is The Way
Staff member
Location
Mandalor
a lot of the comments in here are the same comments that were in the dirtbike world in the early 2000's.... 4 strokes are for racing, they are too heavy, they will never take over freestyle. well 4 stroke 450's are now better than 2 stroke 250's in almost every way.....
Not to take anything away from the Spark Rocket but this couldn't be any more of an inaccurate reference. The modern 450s are better in every way because they have 10+ years of advanced technology in their design, the two stroke engine is still a more efficient engine, a 450cc two stroke would make more power than the 450 thumper. The four strokes were pushed by the EPA, causing the major manufacturers to shift production, when they did, they dumped enormous amounts of money into that tech, the race teams followed (because all big race teams are factory backed), the four stroke became the new standard.


Aside from that, I am really excited to see this ski at 110 horsepower. I have ridden a tuned spark and it was no slouch.
 
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Not to take anything away from the Spark Rocket but this couldn't be any more of an inaccurate reference. The modern 450s are better in every way because they have 10+ years of advanced technology in their design, the two stroke engine is still a more efficient engine, a 450cc two stroke would make more power than the 450 thumper.
Efficient could possiblly be the worst word to describe a two stroke. They can make nearly twice the power per cc as a four stroke, but that's because they process twice as much air and probably more than twice as much fuel per revolution. Four strokes are efficient, two strokes are brute power.
 

King Kang

Never enough tray time...
Location
Cary, NC
Efficient could possiblly be the worst word to describe a two stroke. They can make nearly twice the power per cc as a four stroke, but that's because they process twice as much air and probably more than twice as much fuel per revolution. Four strokes are efficient, two strokes are brute power.

I think he was trying to say they're efficient when you compare power to displacement. You're right though, there are lots of ways to evaluate efficiency.
 

Quinc

Buy a Superjet
Location
California
Company in Australia is building two stroke engines that trump 4 strokes in every way. From cars to boats.

Two strokes strike back

Motorcycle News, June 10, 2009
Written by Guy Procter

KTM has announced record 2008 sales of 25,000 two-stroke bikes and says it sees no end to the high-performance two-stroke. Australian firm Orbital is testing a 200bhp, fully emissions-compliant 1000cc twin that’s lighter and more fuel efficient than any rival four-stroke. Aprilia craves an accessible performance middleweight, says it could easily render its seminal RS250 Euro-3 compliant and has twice already come close to releasing such a bike. R&D departments in Europe, Asia and North America are arriving at the same conclusion: everything you know about two-strokes is wrong, and their revenge against the four-stroke is imminent.
 

N3vrSat1sfied

Military Member
Location
Fort Worth, TX
Company in Australia is building two stroke engines that trump 4 strokes in every way. From cars to boats.

Two strokes strike back

Motorcycle News, June 10, 2009
Written by Guy Procter

KTM has announced record 2008 sales of 25,000 two-stroke bikes and says it sees no end to the high-performance two-stroke. Australian firm Orbital is testing a 200bhp, fully emissions-compliant 1000cc twin that’s lighter and more fuel efficient than any rival four-stroke. Aprilia craves an accessible performance middleweight, says it could easily render its seminal RS250 Euro-3 compliant and has twice already come close to releasing such a bike. R&D departments in Europe, Asia and North America are arriving at the same conclusion: everything you know about two-strokes is wrong, and their revenge against the four-stroke is imminent.


Austria, not Austrailia. but KTM is the SheezKnezz.
 
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