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Discussion Starter #1 (Edited)
Alright guys. I spent most of the weekend getting my bike to run right. 2002 1500. Just picked it up and it sat for a few years. The guy I got it from installed Cobra long shots. No baffles (love it). I do have the receipt that the bike was jetted at the dealer. When I got the bike it would not run. Pulled the carb and cleaned it out and of course forgot to look at jet size. But I do remember pilot being 45. Main jet and Pilot jet were clogged. Drained fuel tank and replaced fuel. Added seafoam. Put it back together and she fires right up. Idles great. But has a stumble off idle. So I adjust mixture screw to 4 turns out no change. Finally I pulled the slide out and put the needle on the 4 th slot and it has 2 shims in there already. That fixed it.

So my question is this. Bike runs perfect now. Should I leave it ? 4 turns out with needle on the 4th slot. I am thinking it should get a 48 pilot and a Baron mixture screw. But on the other side I should leave well enough alone. BTW I love this bike. Bike does feel stronger at the 4th slot even at wide open.

Thanks for any opinion

Steve
 

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You should not have to turn your air mix screw out more than 1-3/4- to 2-1/2 turns.
Has the carb been torn down and cleaned and inspected for tears in the rubber bits, especially the diaphragms?
Does it have a stock air filter or a hi-flow aftermarket?

A 45 pilot jet is common for bikes with aftermarket pipes. Main jets are another matter, and it depends on your air delivery. Try to buy OEM jets if you can, as Keihin, Dynojet and Mikuni all use different numbers for the same size jets. My stock Keihin jet was a 138. I ordered a Dynojet and went with a 140, which is the equivalent of a Keihin 152. Bear in mind, I experimented with different jets as it is a trial and error proposition. No matter what anyone tells you there is no one size fits all. All bikes are different, the mods are different, the riders are different, the geography and humidity and temperature and air pressure your state's fuel blend requirements... and it depends on if you want more low end torque or more top end highway fuel efficiency. All those variables and more means a frustrating series of taking it apart and putting it back together. I'll run it for awhile and see what it does, and then narrow down what I need to do to fix it. Sometimes I go too far and have to undo some of the changes. I have probably had my tank off and carb pulled off at least 3 dozen times. but I finally hit the sweet spot and I'm leaving it alone.

If I have learned anything through this process the past 15 years, it's this: don't make big changes when it comes to fuel systems. A little change can make a big difference. And I don't make multiple changes at once, or you won't know what fixed it or what caused the new problem and it will take longer to figure out. Guess how I found this out?

I see guys here running 170 mains and getting 33 MPG. That's fine, to each his own. I travel long distances out west where gas stations might be a hundred miles or more apart, so mileage is a big deal to me. In 2006 I ran out of gas in the southern Oregon desert 9 miles from a town because the map showed services, but they ended up being ghost towns all boarded up. It ended up being 145 miles between services. My bike made it 136. A sheriff's deputy brought me some gas after a two hour wait by the side of two lane highway. That's when I decided to try to improve my mileage. Now I get about 45 but I still get good performance. I'm not going to win any drag races, but who cares? I'm a 65- 70 mph all day guy anyway.
 

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Discussion Starter #3
Stock air cleaner. Carb has been overhauled and cleaned. No vaccum leaks. Pipes are Cobra with no baffles. Bike starts and runs perfect. I beleive the 45 pilot jet is stock. Just want to be sure its ok as is are would I gain anything putting in a 48 Pilot jet and a Baron thumb screw.
 

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If the air is stock, you shouldn't need to rejet at all. It is only when you introduce a higher air volume filter, like a K&N or air kit, where you'd need to rejet. When I did mine, I did air, pipes and jets at the same time. But lots of guys here leave the stock air and stock jets.

The thumb screw is nice, but I removed my crossove tube when I did my air kit so I can just get my hand in there to turn it without taking the tank off and the carb out. I don't think you'd be able to reach it to get at it with the crossover tube in place.
 

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Discussion Starter #5
Thanks Patrick. I filled the gas tank and put a can of seafoam in just to be sure everything is clean. I drove this bike with and with out air cleaner installed. I really dont feel a difference in normal driving. Maybe WOT but I dont care about that. I can get 1 finger in each side of carb so I could adjust the thumb screw. I guess I could put that in at least.
 
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