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Discussion Starter #1
I originally put this thread in the Motor section but I had no replies so may be Ill get some thoughts and suggestions here.
I put a K&N 8.5" filter and Moroso cover on my 2002 1500 like on Gadgets site. And was wondering about air flow. The original tube that connected the left side air filter and right side is only about 4 sq. inches for air to move to the carb. What if I took some thin steel cut it wide enough to cover the filter and long enough to go all the way around the filter and drilled a few holes in the metal to restrict the air flow back to about what it would be able to draw with the original system.
May be able to avoid re-jetting. Any opinions out there on this. Anyone able to calculate how many and how big of holes.
Or may be just cut the band of metal a bit narrower than the filter to restrict air intake. thanks for any suggestions. I have a 170 main jet but would like to stay stock for gas mileage.
 

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Why not just rejet? K&N is a high flow filter, and merely returning the same air flow to the bike as stock would still be too much air. If you do it right, you can still get 40-45 MPG out of it, and better performance.
 

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Why not just rejet? K&N is a high flow filter, and merely returning the same air flow to the bike as stock would still be too much air. If you do it right, you can still get 40-45 MPG out of it, and better performance.
I went ahead and put the 170 main jet in It had a 138 in it. Seems to start good but it stumbles at low rpm's
and a couple times it backfired when I just cranked the throttle. I couldnt tell if the pop was in the carb or exhaust. I took it down the road and a very slight hesitation till it gets to about 1/3 throttle then it smooths out and really runs smooth and flies. It does not seem to be running hot. I had it running in the garage for 15 minutes and the fan only came on 3 times and quickly went back off. Any suggestions on the low speed stumble?
 

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How many full turns out did you use on the pilot screw?
 

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How many full turns out did you use on the pilot screw?
Its out 4 turns it was out a bit over 3 I increased it to 3 1/2 and a bit better then took it to 4. now I have no popping but if you very slowly open the throttle it still has a slight stumbling till about 1/8 throttle open. Starts easier now. according to the manual it should have a #45 pilot jet in it. When I ordered the main jet I also ordered a #48 pilot jet. I may put that in and screw in the pilot screw back in to 2 turns and try that. Or tell me what you suggest. Ive read that once you get to 4 turns out you may want to go bigger with the pilot jet. I also pulled a plug before going from 3.5 to 4 and they were a bit greyish going to tan.
 

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There's your problem. Your pilot jet is way too small. You shouldn't have to turn it out more than 1-3/4 to 3 turns. 2 to 2-1/2 is idea; any more than 3 turns and your pilot circuit is starving for gas. The 48 should fix that.

happy roads!
 

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I went ahead and put it in yesterday. It did help. Im just waiting for good weather to run it and check plugs. I pulled plugs yesterday after letting it idle a good while and they were greyish and not brown or tan and that was at ideling with a few fun rev ups. But for the most part I did not have any pops or backfires and the gradual throttle was quite a bit better.

There's your problem. Your pilot jet is way too small. You shouldn't have to turn it out more than 1-3/4 to 3 turns. 2 to 2-1/2 is idea; any more than 3 turns and your pilot circuit is starving for gas. The 48 should fix that.

happy roads!
 
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