650sx build by: my650sux
- Thread starter Joe Dart
- Start date
- Location
- Chicago
Looking really good. I like your metal fabrication and craftsmanship skills. Modding the wetjet pipe because its cheaper than a b pipe? I can't blame you, but that big cast thing surely is heavier than a b pipe right?
Thanks! Yeah the wetjet pipe is super heavy. I'm thinking about continuing on with the wetjet pipe just for a baseline run then building my own dry pipe. The 2stroke tuners handbook gives all the math and its pretty straight forward. Reaching a true tuned length would probably mean welding it up, running it to the lake and then coming back to the house and cutting half an inch out of the pipe several times but much better than spending 1500 bones. To add tunability I was planning to tap my pump, run dual cooling and use very small ball valves to contol flow and thus temperature in the exhaust. Because sound waves will travel faster in a hotter chamber, cooling the chamber would essentially make the chamber bigger lowering "power band". Might take a while but I just think it would be cool to make my own true tuned dry exhaust. (Basically jacketed pipe).
I also got my 701 porting templates in the mail today so I need to start on that. Hopefully this thing will rip when I'm done! If nothing else it will be all shinny when I pull the hood.
I also got my 701 porting templates in the mail today so I need to start on that. Hopefully this thing will rip when I'm done! If nothing else it will be all shinny when I pull the hood.
- Location
- Chicago
Making your own pipe is ambitious and will be very cool if you can pull it off. You can also check your math against current pipes which are out there. I'm sure guys would be happy to take some measurements of whatever you'd like. From what I've read and have heard from those with the knowledge in this industry, there are only a few people who can really design pipes well. And even if you know what you're doing, it takes ton of trial and error. Starting with the dimensions of that wet jet pipe will help for sure. It sounds like you're on the right track.
What impeller are you going to run? One big reason why SJ's have good bottom end is because of their larger pump. Also because their engines have lower port timing than Kawasakis. I highly recommend a hooker impeller or at the very least a good C75 swirl. I built a 750 dual carb 650sx which had a oem sxr impeller machined for lightness and repitched to 11.5/18.5. That was a fantastic impeller for that ski. I've got a short write up about it in the individual builds section on pwctoday. It was a great ski for the money I had invested. Had better low end than all the limited 750s we have in our riding group. I think a combination of that impeller and the lower weight of the 650sx really helps.
What impeller are you going to run? One big reason why SJ's have good bottom end is because of their larger pump. Also because their engines have lower port timing than Kawasakis. I highly recommend a hooker impeller or at the very least a good C75 swirl. I built a 750 dual carb 650sx which had a oem sxr impeller machined for lightness and repitched to 11.5/18.5. That was a fantastic impeller for that ski. I've got a short write up about it in the individual builds section on pwctoday. It was a great ski for the money I had invested. Had better low end than all the limited 750s we have in our riding group. I think a combination of that impeller and the lower weight of the 650sx really helps.
I have already installed a hooker 9-13 prop with a blowson freestyle cone for low end. I think with the combination of that and the 701 it should be much better for surf riding. Oh and I also D-cut my ocean pro extended ride plate and installed a worx scooper pick-up grate. Post a link up to your build and I will check it out!
- Location
- Chicago
Here you go. Also have some comparison to other skis we had out. And that hooker is money well spent!
http://www.pwctoday.com/showthread.php?t=452215&highlight=
http://www.pwctoday.com/showthread.php?t=452215&highlight=
Built a bilge pump mount after work today no more dip ties. I would take a pic of it in the hull but it's pretty gross right now. It mounts to the output shaft through hull bolts. I also had to use spare screws for the bottom of the bilge, stainless screws are on my list. The screen is a stainless window screen all hacked up and recycled.
I cleaned the hull up and took a pic of the pump mount in place, also spent some time on the exhaust. My length of pipe is random it will be cut down as well as the expansion chamber. Once i get my tuned length right, I will build another layer over this on and make it a jacketed dry pipe.5" diameter expansion chamber
5-1.75" cone with 19.93° angle
Tuned length should be ~45"
- Location
- Chicago
Looking good. Post up your thoughts on tuning and performance as you cut the pipe shorter.
Hell yea on building a pipe bro.
- Location
- Stouffville, Ontario
This is next level craftsmanship. Sub'd
Thanks guys! I have started an aluminum hand pole as well. I'll take some pictures of my progress after work and post them. The motor is done and sitting on a shelf all sealed up until I get the pole and scupper valve installed. I'm also considering running rear exit exhaust. That means I have to make a new water box but that's no big deal.
Once you find what runs well make templates so you can replicate it down the road.
cookn
Kamikaze
- Location
- where you live
you put more time into your drawings then I do into my whole ski build lol. I can appreciate the dedication that this takes. Your aluminum welds look mint too.
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
I'm going to have to buy some of that graph paper.
Haha, I like to draw it before I try and build it. Plus it helps someone else out when they need to make something.
@Nottjbarlow What's that pipe to?
@Nottjbarlow What's that pipe to?
