after installing wiseco piston and white bros cam my 98 wolverine is smoking during the first minute after cold start up. anybody tell me why?

 

YOUR RINGS ARE NOT SEATED YET!!!!!
IF it does'nt stop smoking after a few miles,you are takin her back down !
Hopefully you checked ring gap and also there is a pin in the ring grooves. thats where the ring gap is suppose to be?

 

thanks for your response monster. the piston and cam have been in the bike now for six months. compression is 130 with this combo. i took the bike apart 1 month ago again to combat the smoking problem and found that oil seemed to be entering the intake side of the head as there was heavy oil residue present. when i put the cam and piston in i installed new valve seals and upon inspection on the second teardown they seemed fine as was the condition of my cylinder and rings. i took the head to a pro technician to have it porterd and polished while it was off and he not only did this work but measured the guides and stems and installed new seals again. after approx. three tanks of gas i am back to the same problem, smoke only on cold start. after it runs a minute it does not smoke any more and other than oil consuption this bike is a rocket ship and has never worked better. now here is the weirdest thing, sometimes it smokes worse than other times. help!!!

 

Try adjusting your mixture screw located under the carb. How is it idling? What color is the smoke?

 

the engine is running fine, the idle screw is set at 3 turns and it idles perfectly. the smoke is blue and is definitely oil smoke, but like i said it is at initial start up only and sometimes its worse than others.

 

It almost sounds like your Wiesco piston is slightly undersized and needs to expand before it fills the cylinder. Does that make sense?

 

iam not ruling anything out, but i would think that if the piston or rings were the problem that eventually this problem would intensify ie: piston slap, more smoking problems during running and a general decline in performance. this bike is running the best it ever has. what i was wondering is where the bike was not even using an ounce of oil before initial disassembly i installed a standard size piston and rings and only deglazed the cylinder. could it be possible that it works good because the top rings seated and the oil rings did not? the only discrepancies that seem to indicate that this is not the problem is the fact that it should smoke all the time should it not and the fact that oil residue was in the intake side of the head while the exhaust was certainly not spotless but was much cleaner than the intake indicating top end problem?

 

Im thinkin that it is the intake valve seal. I know you said it was new, but maybe it was damaged when it was installed, or the spring around it broke, or it wasnt seated properly. Oil has to be seeping down the valve and onto the piston when it sets for a while. Is your filter over oiled. Could be sucking small amount of oil in and mixing it in with the fuel in the bowl. I dont know..just a thought. I will keep thinkin on this one.

 

i tend to agree boomer that there is something wrong in the intake area. i put the first set of seals in myself when i installed the cam and piston in dec. the smoking bothered me so bad even though the bike was working really well i disassembled it again in may to have a look and could find nothing wrong that i could tell. i decided to port and polish the head while it was off and had it done by an exp. technician from a local shop. he installed new seals in the process and said he found nothing significant with the ones i recently installed. the bike is smoking again this time like the last, and i am assuming it is the intake side again but i havent taken it apart yet. do you have to be really careful installing these seals? are they that temperamental or is there another possibility in the head we are missing? maybe my local shop recieved a bad batch of seals, they are genuine yamaha seals. i will remove the carb over the next couple of days and peek inside.

 

your not alone, mine too did this, it has stoped now i think i may have had too much oil in it, not sure, I would asumme its a valve seal because it does it only when cold, I little puff on start up is common in cold weather, but when its 70-90 degrees you should see very little maybe just a whisp.p.s I have a stock engine with only 40-60 hrs on it.