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· Does not know Everything !
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Can you be more precise about what is happening ?

Is it at full throttle, part throttle, rolling on or off the throttle, coming down from high speed etc.

· Registered
1,174 Posts
Two strokes get a miss fire at half the revs at which they make peak power. Usyally 4.5-5.5K on a Cagiva. This is becuase all the exhuast harmonics are 180 degrees out of phase. It's the downside of having a tuned expansion chamber.

· Registered
122 Posts
Discussion Starter · #6 ·
Its at all throttle range, i have changed the spark plug no difference tho. i thought it might be the power valve kicking in?! its ok after it sputters at 4-5 it goes reli well

· Registered
91 Posts
what is the needle slot ie the c clip you may need to drop the needle i found like i said to someone on here before that i needed to drop the needle but by moving her down she was a little weak so by puting a small and i mean small washer under the c clip so i was on pin 3 moved to pin 2 and by putting a washer under the c clip it pin 2.5

and man she off but im a 34 mm myself

my set up is (carb)

165 main jet
50 idel jet
12.5 slide venchury and not the 8.5 as that is to rich
air screw set at 2 turns
and like i said pin 2.5 useing a small washer
6.5g flots (standerd)

you get mid range splutter due to being a little rich and you need to drop the needle but like i said doing so she may be a little weak but dont panic she will not blow as she has it own oil feed as you dont pre mix in tank
so dont worry

if you find you drop it to pin 2 or if you on 4 and move it to 3 well you get the idea you may need to move it up a little bit so find a small washer or put one more c clip under the c clip witch is there already.

so say but moving the needle up or down it like changing the main jet up or down 3 or 4 jet sizes
but i see it say if you bottom end is spot on so is the top then by moving the needle down one may help but you may find that the low is weak so you can screw the air screw in cutting of the air like you may turn it 1 whole turn and guess what she is a1

has the prblem only started or has it been for some time i mean did you have this problem in the colderd weather or do you just ride in the summer time as one of my bike sorry to say and yes it was a aprilia
and she sat for some time in the winter when i come to drive she was rich ie running like what your say and i found that the oil went fun
ie thick and all sh*tty and i only found this as when i was working on it to see what the prblem was i knock the oil pipe and went to the beach to work on the carb all the oil went on the floor put new oil in found sod all wrong with carb and would you belive she was good again

sorry it was a bit long but i hope you get her sorted as i have had my problems and know what it is like you want to ride on a nice hot summers day but she becomes a dog

good luck keep me post and updated if you get it sorted

· Premium Member
10,017 Posts
wtf dale!!! 2007 last post lol the guys prop got a family ,kids n a people carrier by now lol
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