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xjr90 power problems

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Hey i just bought a pitster pro xjr90 and it has major bogging problems off the start and it seems a bit underpowered. Are there smog restrictions or something i am missing? Any suggestions on possible solutions will be appreciated. As for the power question should i be able to wheelie?

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I bought a couple of them and check the air screw first. It is on the front of the carb on the bottom by the float bowl. Mine were pretty much tight or all the way in. 2 1/2 - 3 turns out made a big difference. I think these bikes rip.

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Thanks I will check that, as for general power what should i expect? i know that is somewhat general but i weigh 165 pounds and just feel its not what i expected.

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go by this and you cant go wrong:

1) GET A PLUG READING: You need to run the bike in as tall of a gear as you can. and then kill the engine with the throttle wide open. Dont idle the engine, now remove the spark plug and look at the INSULATOR, the white porcelain part. as a rule it should look like coffee and cream( TAN ) If its Dark brown or sooty black your motor is running RICH. A gray ashy or white reading means its running LEAN. A plug reading only gives you an overall view of how the motor is running.

Do this with a new plug and make sure your bike is warm first.

2) THE MAIN JET: The carbs main jet affects how the carb works from half to full throttle After you have made your test run with the stock jetting. Install a main jet that is two sizes richer it will have a higher number than you removed. do your test run again, pay attention to how the bike feels. If your bike is reluctant to REV out like before, then you are too rich. Now go back and install the next smaller main jet keep doing this until you feel a noticable improvement in power once you have the main jet set go on to your pilot jet.

3) PILOT JET: The pilot jet has the greatest influence from idle to 1/4 throttle to test the pilot jet that is two sizes richer (just like the main jet) now go out and test it pay attention to how its feels when you pull out of the slow turns. If your bike is too rich it will feel sluggish and unresponcive untill you are past 1/4 throttle A perfectly tuned pilot jet will help your bike accelerate off the line and out of corners. Repete this test until you get one that feels the best.

4) THE AIR SCREW: How to adjust it, with a warm engine bring the bike up to a steady throttle setting (about 1800 rpms) get a friend to hold the throttle steady......Once the engine is running at fast idle. Turn the air screw in clockwise until the engine rpm drops. Then slowly turn the air screw out until engine rpms pickup.....Stop turning the air screw once the RPMs reaches its peak. Peak rpms is when the engine runs its cleanest and fastest. The most common air screw adjustment is from 1/2 a turn to 2 turns out. If your air screw is more than 2 turns out it is a warning that you should switch to the next LEANEST PILOT JET....If the engine has peaked before turning a 1/2 turn out. Then switch to the next largest Pilot jet.....

5) NEEDLE JET: Your carbs needle affects throttle settings from 1/4 to 3/4 turns lucky you dont have to replace the needle to adjust. Start out with the clip in the middle setting make a couple of runs, then change the clip down two positions. This is the quickest and fastest improvement you can make to the bikes jetting. Dont be afraid to move the clip up..LEANER or down..RICHER. You spend most of your time riding in this range.

Try all clip positions on the needle see what runs the best.... If you find your clip position at the very top or bottom. then you need to go back to your main jet and pilot jet and make a different setting...

When all is done your clip should be in one of the three middle notches.

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I have no problem pulling wheelies and compared to an Orion 125 (zonger) that I used to have its way faster. I'm 175# and think it runs great. Its not my x4r but is a lot of fun.

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A starting point for the jetting that my Pitster dealer suggested was 17.5 pilot, 95 or 100 main, needle in middle and air screw 2 turns out.

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Just so you don't get confused when tuning that thing, the screw you refer to on that particular carb is a fuel screw not an air screw. Turn it in to lean the mixture and out to richen. Just the opposite of an air screw which is what your X2's and X4's have.

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