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Discussion Starter #1
Ok, so I hear that piston wash is the most accurate way to read how rich/lean you're running. Last night I pulled the plugs on my 1998 XCR 700 to take a look. I bought a light from a store so I can feed it through the plug hole and take a look. First of all, the plugs are not as cinnamon/cardboard brown as I'd like to see them. Upon looking into the plug hole, my wash is easily bigger than my thumbnail - and on the mag cylinder it goes all way across - like a bow tie. Well more like this: >< - so my question is - what do I go by? The sled ran nice and cool the whole time I had it out, but it also used less gas than my XLT.

I should note this is NOT from a plug chop (WFO for 1/2 mile) as there wasn't enough room to open this thing up like that. Plus I'm a little scared to do that based on my initial plug readings.

Bryan
 

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You could try dropping 1-2 jet size across the board. I try to use both color and wash to determine the jettting.
 

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Discussion Starter #3
So I'm for sure running a little rich?

I know my mains are one lower than stock.

Moving the clip on the needle is equivelant to what? Moving one jet size?

Story goes, that when i was out last weekend I pulled the plugs but didn't check the wash. I couldn't- I was at a buddy's house and didn't have the light. Like I said earlier the plugs looked lean so I dropped the clip on the needle down one to richen it up a little, just to be safe. I think I'll put the clip back where it was and wait till I can do some WFO runs on it to see for sure. I should be safe, right?

Bryan
 

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Normally you can easily drop 1-2 main jets sizes from stock. The needle controls your 1/4-3/4 throttle and then the main takes over. How long had you rode it before checking plugs. It does take awhile for the color to appear on them.

I normally drop 1 size guranteed on my sleds. On the 440 it is supposed to be a hot dog sled and I have dropped 1 size with no issues in 3 years. On the 700 I dropped 2 sizes with no issues.
 

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Do not drop you needle on that sled. Down one size on main at 1000 ft elevation should be safe for long wide open runs- just what that sled is set up to do.

It takes some time for wash to show, plugs are quicker. Wait till it's cold and take it for a haul.
 
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