suggestions... deccel smoking problem
 

Hey all~
My Telefonica sixxer started smoking mid-way through a 300 mile thrashing ride (hit the rev limiter at least twice that day trying to keep up with 750s and 1000s). It only smokes on deccel. I get a plume of smoke about 3 feet long on deccel and one more quick puff when I get back into the gas then nothing at steady throttle. If I stay even on the throttle and whack it nothing (that I or anyone else can see anyway). Hard through the gears nothing, maybe just maybe a tiny bit if the shift isn't lightning quick. Nothing at steady cruising speed. But like I said, a fair amount on deccel- always.
My dealer is on happy pills I think and not alarmed by this at all..."don't worry about it, it's fine!" and I am freaked out by it. At the very least it's embarassing. My gutt feelings are that something is wrong (duh). Maybe I floated a valve and bonked a valve seal, maybe I have a damaged valve or valve seat (valve guide?). One person (BMW mechanic) suggested maybe I cracked an oil wiper ring.
In the meantime my dealer wants me to run a tank of gas with shock levels of Ring Free (Yamaha chemical product they swear by), then change the oil. They think the problem will be gone. I don't put any faith in fix-all chemical products like that so I'm not too enthusiastic about it, but I'll do it cuz it's a cheap first step. Next is a leak-down test.
So.....(deep breath) any suggestions here folks? Anyone had a similar problem? I should be worried huh?

oh ya, I forgot to mention that the bike has 7,300 miles on it, and I replaced the plugs to see if that would fix the problem. The plugs had no affect. The bike is running flawless, smooth idle, good power, not using any noticable amount of oil.

sounds like a some rings are letting oil by on the deceleration.
fix all crap I don't believe in ,but a cheap try , just maybeee,

Man, that doesn't sound good at all. Here's what I would try if the chemical elixer doesn't cure it. Get the bike to do its smokey decel while approaching your house. As soon as she starts to smoke, pull in the clutch, hit the kill switch, and let it coast into your driveway. pull the plugs, and see which one is oily. That should give you a good clue as to which cylinder is the culprit. Then I'd definately do a leak down test. At least that will tell you if your valves are causing this. If you do have a messed up oil ring, I don't think it will show up doing that test. Unfortunately, it looks like you may now have yourself a winter project.

hmmm, thanks for the replies guys, especially Junkyard. That's a neat trick I have not heard of before. I may try that. But then I might not have to because here is the latest:
I put the Ring Free in the tank last night (12 oz to 4.8 gallons of gas, what they call a shock treatment) . Fired the bike up, right off the bat going down the street no smoke that I can see on deccel. The day before I didn't have to strain to see it, a quick glance in the mirror and it was easy to see it, last night... nothing. There's no way the chemical started working that quickly so how could the bike smoke one day and then fix itself sitting in the garage overnight? I still have to get someone to go riding with me and see if there's a faint amount that I can't see, but it looks to me like the problem stopped. Now I have to change the oil because using the Ring Free in shock levels supposedly contaminates the oil. I will change the oil tonight and ride it again and see if the smoking is there. This is the weirdest thing I've ever had happen.
Oh ya, and about the plugs, they did not look too bad. I'm running a bit rich, not excessive though. No one plug was worse than another, all looked the same (which is good). I do have to say that the bike is running amazingly well. There is no indicator performance-wise that anything is wrong.
Thanks again guys.

oh and one more thing, if Junkyard is right and I have a winter project on my hands, I'm going nuts, bore job, stroked, hi-po pistons, flowed head, pcIII the whole nine yards and making this sucker a liter-bike eater. WooHoo!!

I'm not hoping you have to tear the motor down, but tricking out the GSX sounds awsome. You'd definately have a bunch of guys on liter bikes wondering what the hell just smoked 'em :eek: (no pun intended!)

Anyone else think a compression test might be an idea as well. Isn't that a good indicator of ring life? Sounds to me like a little oil got above the piston and was burning off. Maybe it's gone now, hard tellin without taking the motor down a little bit. To me, having had several Gixxer's and built 3 motors for drag racing, it doesn't sound like a huge problem. I've seen a lot of motors that smoke on accel and deccel run 9's in the 1/4. If it were me, I would do a compression test, change plugs (already did I know), change the oil and get back on it. If anything, pull the head and have the valves checked too, but I don't think the motor needs rebuilt. my .02.

PS: I don't think the chemicals fixed it either.

chemicals??
well here is a trick many used car lots use
they put in mobil 1 oil
as it will not smoke,
but after you purchase the auto and change the oil to someting else, guess what ??? you see the smoker.......

Mobile 1 doesn't smoke? seriously?

oh, and FatBoy, if the smoking continues then yes, a compression test and leak down test are next.

yes I wouldn't shit ya ,,,,,,

update: smoking stopped all on it's own. I put the Ring Free in the tank but the bike wasn't smoking right out of the driveway. No way the chemical could have worked that quickly (while warming up). I'm perplexed but happy for now.

so now that the bike is back in my good graces I bought it a present (new exhaust hanger) and turned it's heel plates into drillium. check it out

Good to hear the smoking problem is fixed beautiful bike i must add...