- Location
- Pac NW
Just registered today. This is my first post (hopefully I don't screw up). Cheers to everyone. Rode 650sx's years ago but upgraded to a boat when kids came along. Got the itch big time to get back onto a stand-up, so when I came across a 97 superjet with numerous mods at a dirt bike dealership I picked it up. The problem is that the dealership picked the unit up somewhere in Washington or Oregon and they have no history on the machine. Obvious mods include "B" pipe, msd ignition/leads, worx intake grate, jet dynamics plate, tau ceti arrestors/riva adapters, greater yamaha girdled head, s/s impellor, umi bars & steering kit, pole shortened 2", side sponsons, bilge pump. I trust the guy that sold it to me when he said that it goes like hell compared to the stock 04 sxr he also has for sale. My questions are as follows:
1- There are two lead fishing weights (@ 5-10lbs) epoxyed inside the hull behind the engine. Are these to prevent porpoising during racing. Sould I remove them for freestyle/play riding?
2- The impellor appears flawless, however, it looks like it has been "ground or polished" on the faces of the blades. I can't see any markings on the unit looking down the shaft so I don't know the brand or pitch. I've read something about impellors being "shaved" What is this, and does this sound like my impellor?
3- Is there any way of telling if there is aftermarket reeds on the boat without removing the carbs and ruining the gaskets?
4- Unit has twin Mikuni carbs. How can I tell if they are stock, or modified? Should I look for obvious markings or modifications?
5- Lastly, I am a little worried when I checked the compression. I am only getting 145# on both jugs with my cheap compression guage. I thought that I should have more with the girdled head. I am going to pick up a snap-on gauge and recheck next week. The question is, how can I tell the displacement (cc) of the domes in the head. I checked Greater Yamaha's website and they don't even list this head anymore. I'm not sure if I can even get replacement domes for this head. If the boat was set up for racing, what would be the best guess on dome displacement? If it sounds like the top end is getting tired, are there consequences to riding this way for another season, or will it just lack power. Does lower compression reduce bottom end power, topend, or over the entire powerband?
Thanks in advance.
1- There are two lead fishing weights (@ 5-10lbs) epoxyed inside the hull behind the engine. Are these to prevent porpoising during racing. Sould I remove them for freestyle/play riding?
2- The impellor appears flawless, however, it looks like it has been "ground or polished" on the faces of the blades. I can't see any markings on the unit looking down the shaft so I don't know the brand or pitch. I've read something about impellors being "shaved" What is this, and does this sound like my impellor?
3- Is there any way of telling if there is aftermarket reeds on the boat without removing the carbs and ruining the gaskets?
4- Unit has twin Mikuni carbs. How can I tell if they are stock, or modified? Should I look for obvious markings or modifications?
5- Lastly, I am a little worried when I checked the compression. I am only getting 145# on both jugs with my cheap compression guage. I thought that I should have more with the girdled head. I am going to pick up a snap-on gauge and recheck next week. The question is, how can I tell the displacement (cc) of the domes in the head. I checked Greater Yamaha's website and they don't even list this head anymore. I'm not sure if I can even get replacement domes for this head. If the boat was set up for racing, what would be the best guess on dome displacement? If it sounds like the top end is getting tired, are there consequences to riding this way for another season, or will it just lack power. Does lower compression reduce bottom end power, topend, or over the entire powerband?
Thanks in advance.