Excessive Blue Smoke From yz250 Exhuast

[Hugh Jass]

I have a yz 250 that emits excessive blue smoke from the exhaust. Could this be i'm running to rich? Im mixing 32:1. Also what is the best oil to use for my bike.I've heard yamalube isnt that great.

[Zilla529R]

Could be rich, but then again it could be blown crank seals. I personally run Maxima K2 and its really good oil.

[$evy]

Klotz techniplate tcw-3, great oil and smells yummy when it burns...

[pinger.j.]

im runningim runnin amsoil dominator at 50:1

[Smokin'Gun]

Klotz techniplate or maxima castor927 mixed at 32:1 will be fine. Your blue smoke means that its running rich with too much oil. Run it at 40:1 there wont me much smoke.

[SickCRrider125]

i took this quote from another site.."Rich and lean is sometimes a difficult concept to grasp, even among some seasoned riders I've talked to. When referring to a rich or lean mixture, it just refers to the fuel air ratio and not the gas/oil ratio. If you're running a 32:1 premix ratio, the engine will be running richer than a 20:1 premix ratio since at 20:1 the extra oil displaces fuel and gives you more air per volume of fuel." so basically adjust your jetting, not your gas/oil ratio

[Zilla529R]

Most likely it is either your jetting or the type of oil you are running. A good oil mixed at 32:1 with proper jetting will produce very very little smoke when warm.

[pinger.j.]

yea he points out a big thing here. 2 strokes smoke alot wehn there cold. if your starting it up and noticing it smoking alot then shutting it off. you have to let it warm up and go ride for a bit once its fully warmed up check if it still smokes if it does it could be a crank seal but checkeverything else first

[Smokin'Gun]

Originally Posted by SickCRrider125

i took this quote from another site.."Rich and lean is sometimes a difficult concept to grasp, even among some seasoned riders I've talked to. When referring to a rich or lean mixture, it just refers to the fuel air ratio and not the gas/oil ratio. If you're running a 32:1 premix ratio, the engine will be running richer than a 20:1 premix ratio since at 20:1 the extra oil displaces fuel and gives you more air per volume of fuel." so basically adjust your jetting, not your gas/oil ratio

Yeah and if you mix your gas/oil 250:1 its going to be a lean mixture in your tank and your quad is going to go sky high. If your gas is mixed 2:1 its going to be a rich gas mixture and your quad isnt even going to run for 2 seconds. Your right most of the time its the fuel/air ratio. But 32:1 with yamalube is going to make excessive smoke because I use 32:1 yamalube when i break in my bike (i run 5 gallons or 2 1/2 bike tanks) and it smokes like a bitch. I used to run 40:1 yamalube all the time and it hardly ever smoked. Running 32:1 castor 927 my bike smokes more than anything but it smells so good and I really dont get a chance to look at the smoke so i dont care.

[Hugh Jass]

Yeah thats a good point. I think i need to let it warm up more.Thx for the replies.