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Thread: Full exhaust jets and pilot screw settings

  1. #21
    Biker phreak911's Avatar
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    One quick question though, did you keep the airflow restrictor plate in when you reassembled the air box? Plastic plate that goes underneath the air filter, has two gauze circular holes in it... I took mine out when I tuned my bike on bigger jets, made a big difference... :-)
    Saint by Day... Sinner by Night!

    Quote Originally Posted by banana.logic
    Your mum affects my sag.
    Quote Originally Posted by Matt
    What. the. fuck.

  2. #22
    Bik
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    Yes i didnt remove the restrictor plate because i heard the bike has flat spots if you remove it
    I'll put on the full exhaust next week so in theory the mixture will get more lean
    So i will just wait and see :-\

  3. #23
    Biker phreak911's Avatar
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    Trial and error, obviously each motor is going to be a little bit different, but removing my restrictor plate took out the flat spot I had between 6 and 8k rpm.
    Saint by Day... Sinner by Night!

    Quote Originally Posted by banana.logic
    Your mum affects my sag.
    Quote Originally Posted by Matt
    What. the. fuck.

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  5. #24
    Bik
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    Thats a good reason to try it! Thanks for the info!

  6. #25
    Bik
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    Full exhaust installed!
    HUGE flat spot at 8000rpm but runs well over 10000.
    Throttle response got worse!
    My setup is 110 112 mains pilot screws 2 turns out..air filter and restrictor plate in place!
    Please advice

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  7. #26
    Biker phreak911's Avatar
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    Okay, my best guess is, you might need to raise your Carb needle height. Try adding one washer to start and see how that affects the "hole". If its gets better, you're on the right track. I suggest you pull the carbs apart and take one of the factory washers to your local bolt shop to match size. The needles should have one each from the factory, I think my current setup is the one from factory plus one more under each needle to raise the needle height. But, for reference sake, I had 115 jets, pilot screws at 2 turns out, one extra washer under each needle, and the restrictor plate still in my bike before I upgraded my cams. Most importantly, only change one thing at a time when chasing a good tune, otherwise you'll be chasing your own tail. Hope that helps.
    Last edited by phreak911; 31st July 2016 at 04:11 AM.
    Saint by Day... Sinner by Night!

    Quote Originally Posted by banana.logic
    Your mum affects my sag.
    Quote Originally Posted by Matt
    What. the. fuck.

  8. #27
    Bik
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    Oh i forgot to mention i already have an extra washer under the needle..so i have 2×0.5mm washers.
    Ι took off the restrictor plate today..it didnt fix the problem.
    I think it is fuel starvation..maybe i should set my pilot screws at 2.5 turns?..or even bigger jets
    Our setup is very similar though..what exhaust do you have?

  9. #28
    Biker phreak911's Avatar
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    I have a Japanese aftermarket brand exhaust, pretty much just a straight through pipe. Opening up your pilot screws will only affect idle. Maybe try bigger main jets, or you might need to raise your needles one more washer height. Hard to diagnose over the web, sorry.
    Saint by Day... Sinner by Night!

    Quote Originally Posted by banana.logic
    Your mum affects my sag.
    Quote Originally Posted by Matt
    What. the. fuck.

  10. #29
    Senior Biker Lane's Avatar
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    I believe you may need bigger mains, I realise your issue is in the midrange but I'd hazard a guess and say you are full throttle throughout your flat spot and during testing?

    115's work a treat with a straight through can, with a full system you may need up to 118's at a guess.

    Mootavic's site is always helpful too.

  11. #30
    Bik
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    Bike hesitates between 4000 and 8500.
    After that range it revs freely
    I will try increasing the pilot screw turns to see if it fixes but i already ordered bigger mains..115 118 and 121
    Full throttle after 10000..no problem
    Full throttle on hesitation point..small improvement

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