650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

Thanks for the heads up. Actually I had a race spec Riva 650 cylinder a while ago which I was going to use. Sold it at some point. I think I'm going to have Newmiller port the cyl I have. Its a 00 00 (perfect sleeve to casting alignment) cyl. Kind of funny that cylinder ended up on a 650LX, the bottom of the bottom 650s. At any rate that cyl is a bit more special than usual. Of course after porting there wont be much benefit but still. It's special to me.

I need to do some research to figure out what's a good target rpm for max hp between a good ported 650 cyl and the Coffmans sizzler pipe. I think I've reached the end of this combination of parts. I don't think it's practical to spin this ski any faster, and I'm not sure a larger impeller could pull this set up as well. A ported cylinder / full 2" exhaust and less restrictive waterbox, raised rev limit CDI, and 18/21 might be a good next combination.

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

A few reference threads from X-H20:

Coffman's vs Factory Pipe:

http://www.x-h2o.com/threads/coffman-vs-b-pipe.66234/

Coffmans Pipe Set Up and Tuning:

http://www.x-h2o.com/threads/coffman-sizzler-setup-and-tuning.152119/

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

My performance tweaks on this ski continue. I bought a 17/21 impeller from Impros to cut down the RPM and gain speed, and that's exactly what I got. Conditions were not ideal, we had strong winds the two days I was out and it was a bit difficult to get clean speed runs. Still as always my runs were done in a big arc to settle the hull on one strake and prevent porpoising. All data was verified by my brother's Aim mychron 5 data logger.


17/21: 49.1mph @ 6850-6900 RPM

17/20 (OLD): 48.5 @ 7060-7080 RPM


All else equal other than the impeller swap. This gives me a little bit of room to try some mods this season. And now that I know approximately what to expect in terms of RPM drop and speed gain, over the winter as funds allow I might have this cylinder ported and up the impeller to 17/22. I think I can get to 50 before then, just by optimizing a few things I've left on the table. For example, believe it or not I'm still using the stock WJ / WR500 waterbox. My pipe exit is 2" but it reduces down to 1.75" which carries through all the way back to the box. The only way I can imagine this has worked is that I really cut down the water that enters the pipe at the stinger.

Can you imagine running a 550/650 or 750 on a stock 550 waterbox? Well if you guys have I'm sure it didn't go well. I wouldn't in a million years. Also of note, I worked forever on my dual carb 550/750 to hit 50. This ski on a single carb does it relatively easily with still a lot of things I can improve. Kind of funny.

So far this is without a doubt my fastest ski for the dollar and for cc / hp. I would be interested to know who has the fastest yamaha 6M6 650 ski today. The engines are really conservatively port timed, and in general considered dogs so it would be interesting to know. Regarding useful comparisons, I have a friend who has a 2015 superjet which is almost to lites spec. Re-jetted carbs, MSD ignition, pipe sleeve, ect.. all the tweaks. He's only missing the cylinder. Our skis are neck and neck off the bottom. Mid range he pulled a few ski lengths, and then at top speed I got him by a few lengths. Overall very close.

Updates will continue to come. This ski still puts a smile on my face.

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

Also of note, this was our first daddy- daughter weekend. My daughter Avie, who just turned 3, came out with me. Although she didn't ride any skis, she was such a trooper. She kept herself completely occupied playing in the sand and with the rocks and shells while Adam and I swapped rides on our skis, and while I was maxing the jammer. Then the next day, Adam's gf Lauryn came out and Avie kept herself and Lauryn busy the entire time we were at the lake with our ski buddies. 11 to 4 or so, in 90 degrees with wind. I'm thankful for Lauryn's help and for how easy and fun it was to have Avie around. At one point I saw Avie leading Lauryn down the row of skis. She wanted to show Lauryn which ones were her favorites. And of course, for anyone who knows Avie, it was all the ones which had either purple or indigo/ blue on them. Lol. She's really getting to a fun age and I look forward to more trips with her in the future!

[CA550sx123]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

Also of note, this was our first daddy- daughter weekend. My daughter Avie, who just turned 3, came out with me. Although she didn't ride any skis, she was such a trooper. She kept herself completely occupied playing in the sand and with the rocks and shells while Adam and I swapped rides on our skis, and while I was maxing the jammer. Then the next day, Adam's gf Lauryn came out and Avie kept herself and Lauryn busy the entire time we were at the lake with our ski buddies. 11 to 4 or so, in 90 degrees with wind. I'm thankful for Lauryn's help and for how easy and fun it was to have Avie around. At one point I saw Avie leading Lauryn down the row of skis. She wanted to show Lauryn which ones were her favorites. And of course, for anyone who knows Avie, it was all the ones which had either purple or indigo/ blue on them. Lol. She's really getting to a fun age and I look forward to more trips with her in the future!

[ATTACH=CONFIG]567593[/ATTACH]

my 2 year old loves our couch, ill never get rid of it cause the kids like it, its 01 gtx di.... fully rebuilt, should last another 130 hours or so.

[JSNate]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

Impressive results, Frank. I dig this build because it is so unique and cool.

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

my 2 year old loves our couch, ill never get rid of it cause the kids like it, its 01 gtx di.... fully rebuilt, should last another 130 hours or so.

That's great! So good to get the kids involved!

[theVetteman3]

Re: 650 Wave Jammer Engine Swap and novice Freeride/ Freestyle ski

Impressive results, Frank. I dig this build because it is so unique and cool.

Thanks Nate. I need to drop you and Kurt a line soon. Been too long since we've seen each other.