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Underside of the carb, front and center. Try the search button at top right of the Thumpertalk page :applause:

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o yea a new problem.opened the air box up top and the bike stalls easy and wont start when hot,battery died and takes a long time to kickstart.i see just about everybody is going to a 170 mainjet.mine is still stock a 145 maybe?should i put a 170 main und a 48 pilot jet?i ride between 600ft to 7000ft elevation and 60 to 100 degrees here in az.

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o yea a new problem.opened the air box up top and the bike stalls easy and wont start when hot,battery died and takes a long time to kickstart.i see just about everybody is going to a 170 mainjet.mine is still stock a 145 maybe?should i put a 170 main und a 48 pilot jet?i ride between 600ft to 7000ft elevation and 60 to 100 degrees here in az.

You have to think of the engine as a balanced pump: air intake, fuel quantity, and exhaust volume are a balanced system. When you mess with one, you upset the balance. Adding more air to the intake will make it worse, unless you add more fuel at the same time. Stock, the motor runs amazingly well for how restricted it is. But you have to de-restrict the motor as a system: more air/morefuel/less backpressure all at the same time.

Since the bike comes delivered extra, extra lean, just re-jetting alone will make an improvement on how strong it runs, but not necessarily on how well it runs : load and throttle postion will seem to have varying effects on power band and torque, and it will vary in a non-liner fashion. There is still an imbalance to the system, but there is more of everything so it runs stronger. That is why it is referred to as 'tuning': there is a balance to maintain as you increase the air/fuel/exhaust levels.

Many of us here, and many professionals, have spent two years trying different combinations of tuning. If you hang around, search and read the threads, you will benifit from decades of combined knowedge one what works, and when it applies to you.

Good luck.

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You have to think of the engine as a balanced pump: air intake, fuel quantity, and exhaust volume are a balanced system. When you mess with one, you upset the balance. Adding more air to the intake will make it worse, unless you add more fuel at the same time. Stock, the motor runs amazingly well for how restricted it is. But you have to de-restrict the motor as a system: more air/morefuel/less backpressure all at the same time.

Since the bike comes delivered extra, extra lean, just re-jetting alone will make an improvement on how strong it runs, but not necessarily on how well it runs : load and throttle postion will seem to have varying effects on power band and torque, and it will vary in a non-liner fashion. There is still an imbalance to the system, but there is more of everything so it runs stronger. That is why it is referred to as 'tuning': there is a balance to maintain as you increase the air/fuel/exhaust levels.

Many of us here, and many professionals, have spent two years trying different combinations of tuning. If you hang around, search and read the threads, you will benifit from decades of combined knowedge one what works, and when it applies to you.

Good luck.

Dude, good post!

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well im an *******,rejeted bike, cleaned carb (2 times) spent the entire day trying to get the bike started to no avail.about 6pm i read the owners manual for the 10th time and decide to take the carb off 1 more time.im thinking i must have missed somthing.well as i take the fuel line off it starts to drip all over me slooooowly.i notice the petcock is on the on position but the fuel is comming out very slowly.put it on reserve and now its flowing realy good.hook up fuel line with petcook on the reserve position and wham starts right up.was i outa gas?no the petcock was cloged :lol: problem solved after 10 hours.:lol::applause:

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Yea definently go with the 48 pilot jet since that is the jet that affects starting.:applause:

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i put a 165 main in,pilot still stock but now starts right up.also raised the needle one position to 4th position.do you think a 48 pilot will make that much differance?

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