alberta guy

I got an 88 550 stand up and it doesn't seem to rip like it should. Its got shaved heads and 157psi compression in both cylinders. A coffman pipe, primer kit, finger throttle, skat track 15.5 pitch prop, aftermarket intake grate and ride plate. I recently also installed a freestyle cone. I rode a bone stock 1989 650 and it was way more powerful than mine. If I hit the revs just right mine rips like theres no tomorrow for about a half a second and is faster than that 650. but otherwise It just doesn't compare that one was stock and mine is heavily modified. I've replaced some of the fuel lines becuase they had pinhole leaks new plugs but i've run out of ideas on wht to check fix ect. Can anyone help me out. and I run synthetic oil mixed 40 to 1

Jimbro

Dude it's all an illusion in your mind. I have a similar ski to yours but now I had to go to a 440 and my ski even for a 440 halls ass. The biggest thing is most of the stand ups like the older 440's and 550's wernt really that fast. If your trying for more tricks than why have any top speed whats the point. With what you have you want torque. The best thing for that is a nice boar and a milled head. The other place Id check out is your carb. Thats probably where you will be able to really set up for more power. If you really want to go the disstance install a sbn 44mm carb and than tell me what you think of the power. Most of your upgrades too are good but wont give you any power. The pipe is nice but get a water box too.

alberta guy

it does have a 44mm carb and a K & N airfilter i forgot to mention that. And I also forgot the head is milled down 40 thou. Top speed is not a issue mine had better top speed than that 650. I guess a better way to describe how it runs would be for the most part it has power off the line and all around like a honda civic. but then you hit those revs just right and pin it, it has power like a corvettefor that half a second. And I just want to figure out how to have that corvette power all of the time.

Grimlock

Did you try increasing the low speed mixture screw, or possible jetting issue

__________________
'91 JS650SX
'89 JS550
'89 JF650X2
'83 JS440

Jimbro

It sounds like your carb screws could be a little off. Maybe there not though but if they are a little off that will make the biggest differance. all around what you want you probably wont get. I mean if you have a big fat pipe like mine waterbox and the rest of what you have on your ski that thing should be fine and pleanty fast and tourqy. If its not these things than you may even have a sand clog happens all the time with these things. Blow out all your lines,even if its not that problem its still a good idea to do it.