Hi all. I've recently gotten myself an 04 SXR-800. Its had a shit of a life with its previous owner judging by the condition of it. The thing SMOKES like buggery.....way more than my Yamaha FX1, running the same fuel to oil mixture. When running it up on the hose, there seems to be a ton of unburnt oil in the water coming out of the back end. Looks like the Exxon Valdez spill happened on my drive way. Well not that bad...but you get the idea. Does this sound like the rings are on their way out? Or are these 800's just notoriously smokey? Thanks.
Congrats on the purchase. I wouldn't jump straight into saying its the rings. Most likely its out of tune, and the carbs probably would benefit from a rebuild kit. Leaking needle and seats, incorrect jetting etc etc can all cause that problem. The SXRs we're jetted quite lean from factory to pass the emissions testing in the USA before they could be sold so didn't really smoke too much at all. That said, if it hasn't had a rebuild in a 4-5 seasons then its worth looking/checking piston clearance and bore wear. Start with a simple compression test and go from there. I would recommend that you pull the carbs, clean them, I'd also throw a carb kit at each of them, and then let us know how its jetted (i.e. lows/highs, needle and seat/spring). If you want a hand just ask, I've raced SXRs for years. Unfortunately I'm based very south auckland but can make it work if you'd like.
Ahhh righto. Ok 'll give the carbs a once over and see how that goes. I'll get my hands on a compression tester to. What compression should an 800 be? What compression would a 'used, but healthy' 800 be, and what would be considered rooted? I forgot to mention is has some performance air filter looking things on it; could they be throwing it out? Cheers for the offer of a hand! I'll probably get stuck in within the next few weeks, and if I run into any trouble, I'll get in touch!
Stock 800 comp is around 150psi. Depending on whether they have re-bored, changed base gaskets, and/or skimmed the head it could be up to 185psi. If its below 120psi then you have issues. If it's been tuned correctly then having air filters won't matter. It will go better with them on but if you're gonna ride it in the surf then get the OEM airbox back on.
Haha cheers for all the offers for a hand guys! Much appreciated. I got a compression tester onto it, and the front cylinder was reading 165 and the rear 152. So its a wee bit of difference, but I don't think its much to worry about? That was cold too. I'm gonna look at the carb next, and see if that could clean it up a bit. At the end of the day, it runs ok, it just smokes like a locomotive thats all.....makes my FX1 look like a Prius.
