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Excessive smoke and spooge 1999 RM250

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I

am getting some excessive smoke and spooge from my 1999 RM250. I never noticed it when I used to ride it since I hardly looked backwards when riding. I can't remember the spooge back then but I can't say it didn't. Anyway, my cousin rides this bike now and when I get behind him it seams to smoke a lot. He doesn’t seam to be on the pipe a lot so I was thinking this could be the reason. Does that sound reasonable? I don’t think he ever visits the main jet and likely not more than 1/2 throttle. I does not foul plugs bet it does get the rear brake wet in spooge. These are the last settings since we rode last.

BR8EG, Main 155 (stock 158), Pilot 42 (stock 45), Needle N1EG position 3 (stock N1EG position 3)

Amsoil Dominator 40:1 (stock 30:1), Airscrew 1 1/2 turns out. Somewhat fresh silencer packing, always, clean oiled air filter. The elevation is 700 feet above sea level, 70 degrees F.

As you could see the pilot and main are one step leaner than stock. The plug is per stock and the oil could make it a bit rich on the air fuel ratio. But the needle is stock and the clip is in the stock position. The top of the piston has a carbon area about less than half of the top and mostly closer to the intake side away from the exhaust. That tells me that it is running OK or closer to the lean side. So why all the smoke and spooge? Perhaps not on the pipe enough to get the exhaust temp up high enough to burn off the oil? Any thoughts.

Also did a leak down and the top was done about 5 to 8 hours ago by myself, so I know it's fresh.

http://www.youtube.com/watch?v=CzwkFIk0CkE

jump to about 45 seconds to see the smoke. I looks not as bad in the video. It seams worse in real life.

I am thinking to be safe perhaps move the clip up one groove to lean out the lower end or go one heat range down on the plug, but not both at the same time for starters.

What do you guys think?????

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So I poked around here a bit and it never occured to me that thr 1999 RM 250 DOES NOT use a BR8EG spark plug. This always seamed a logical choice for a 250 two stroke. It ends up that it is supposed to have a NGK R6918B-7 in it which costs over $25. There are suposed to be some reasons for this and one of them is that the plug makes a better spark with the not so great electrical system of the year and model bike. Also, it is a 7 heat range and not the 8 heat range which I assumed was correct. No that makes me wonder if the previous owner cheaped out and used the BR8EG plug and then needed to jet out the spooge by going one step lower on the pilot and main jets.

Should I put the jetting to stock, needle position to stock and use the proper plug or just put in the propoer plug and give it a shot? I guess most bikes are a tad rich at sea level from the factory for safety sakes and I am at 700 feet. This now has me thinking. What to do.

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I thought about doing that silently as a fix to the spooge but feared of a lynching to mentioning that in public TT. Some people would crucify someone for trying to cure spooge with a hotter plug instead of with jetting. Looks like it ends up that the hotter plug might be the HOT ticket.

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if the stock plug was a 7...I'd start there. It's interesting that you found reference to a unique plug for that machine though.

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