Super Jet Sj 1200

[Vumad]

Overall it was a great experience. I don't want to discourage anyone.

That's fine, but can you explain the complications you had? I would like a SXR hull with a GP1200 motor but more realistically may end up with a SJ hull. I also considered a custom hull with integrated sponsons to allow more space in the engine compartment. I'm interested in your complications so I can plan accordingly. I saw the exhaust routing was an issue and integrated sponsons would have made more room to run the pipe to the waterbox. Etc etc.

I've been on a stock SJ for about 2 years. I just upgraded it to a fully limited SJ. I know that by the end of 2 more years I will want more. I want to start working on a plan, and since it will be complicated to move on from here, I want to start working on it now. I have a 1200 on the bench that is bad that I have been saving for this project. I was thinking of getting a hull for and start working on slowly. Any advice and complications you can explain in detail so I can avoid them from the beginning would be great. Honestly, I think I'd like to work towards a GP1300R motor, but I'm not sure that is realistic.

 

[tshank123]

Vumad, my guess is that it was a tuning nightmare with that 2" exhaust, just like people said it would be. The idea of having to rip it back apart to run 3" was too much for him.

 

[Vumad]

Vumad, my guess is that it was a tuning nightmare with that 2" exhaust, just like people said it would be. The idea of having to rip it back apart to run 3" was too much for him.

I got better performance out of my 750 when I upgraded to a SJ waterbox and B1 outlet (all 2"). I just don't think those motors can run that great being restricted like that.

I did plan on maintaining the 3" exhaust on my 1200, if I ever get to build it.

 

[tshank123]

Its just another reason why people opt for Kawi conversions on blasters and sjs. Its already 2" on a kawi tripple so the exhaust is much easier to deal with, plus the chamber is so much smaller.

 

[Vumad]

Its just another reason why people opt for Kawi conversions on blasters and sjs. Its already 2" on a kawi tripple so the exhaust is much easier to deal with, plus the chamber is so much smaller.

But doesn't the 1200 make a lot more power? The 1100 kawi is rated for 120hp factory and the yamaha 1200 is rated 135hp factory. Who knows if those numbers are right. The Yamaha came with a 155mm pump and the kawi with a 148mm pump, so it's hard to say which is a more powerful engine. The larger pipe and exhaust may be a waste of space or making more power? Does anyone have any knowledge of a kawi 1100 vs a yamaha 1200 side by side throughout the RPM range using similar set ups, say a B1.

 

[tshank123]

Thats an ongoing debate. I've had plenty of debates with people on the very subject. I wouldn't trust the factory hp numbers for this one though, they're both pretty close to each other. I'm a yamaha guy myself, and my blaster 1200 holds its own against kawi blaster 1100s. The 1200 with a stock pipe makes its best power in the high 6000s, whereas the kawis like to run in the high 7000s.