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  #21  
Old 29-01-2013
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n_green n_green is offline
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Rich will bog when revved from idle. May also fall below idle when coming back down in revs and even stall if too rich. When ridden it will be blubbery and smoke more then usual. Wind the air screw out to correct this. Further then 2 - 2.5 turns out go next size up on the pilot.

Lean will be crisp when revved and will take its time to come back down in revs and may even hang just above idle before settling at idle. When ridden will also lack any torque down low. Wind air screw in to correct. Further in then .5 - 1 turn out indicates you need next size down on the pilot.

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  #22  
Old 30-01-2013
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Originally Posted by n_green View Post
Rich will bog when revved from idle. May also fall below idle when coming back down in revs and even stall if too rich. When ridden it will be blubbery and smoke more then usual. Wind the air screw out to correct this. Further then 2 - 2.5 turns out go next size up on the pilot.

Lean will be crisp when revved and will take its time to come back down in revs and may even hang just above idle before settling at idle. When ridden will also lack any torque down low. Wind air screw in to correct. Further in then .5 - 1 turn out indicates you need next size down on the pilot.
You have that around backwards about changing jets. Too rich in the first example you new to go down a pilot size if not getting it with the air screw.

And go up a pilot size if too lean in the second paragraph.

Note: too lean can also make it hesitate off idle.
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  #23  
Old 30-01-2013
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Thanks Keg. I always get that wrong for some reason.
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  #24  
Old 31-01-2013
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Great info, many thanks
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  #25  
Old 03-02-2013
johnt johnt is offline
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Originally Posted by cwbyup View Post
Thanks very much to the OP for spending the time writing all this down. Its very helpful to any one new to 2T tuning.


Just wondering if there is an way to tell the differance between Lean & Rich between idle and 1/4 throttle.

Having trouble working out which way I should be going with Pilot Jet size.

Thanks very much.

Cheers Nick
try riding around in this rev range for a while if the plug fouls or you need to rev it now and again to stop here loading up then its too rich, check your float level use the lean bike over method as i find this more reliable.
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  #26  
Old 03-02-2013
BenKTM250 BenKTM250 is offline
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Great info. Im going to try it out.
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  #27  
Old 27-02-2013
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Help! Help! Help!

I've just been through my carby and set it all as per the instructions on the jd jet kit (half of it was done by the PO).

Now it won't fire. Not with choke, not without. Mix screw at 1.25 turns, 175 main, 42 pilot.

Help!
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  #28  
Old 27-02-2013
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A flutter (lacking power and doesn't kick through band) in the top end, would this indicate to lean on the main jet? A quick slip of the clutch and its on its way again though...
The bike is a 150, so its vital to be spot on otherwise it feels like you going backwards against the bigger bikes.

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  #29  
Old 27-02-2013
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Originally Posted by 1WD View Post
Help! Help! Help!

I've just been through my carby and set it all as per the instructions on the jd jet kit (half of it was done by the PO).

Now it won't fire. Not with choke, not without. Mix screw at 1.25 turns, 175 main, 42 pilot.

Help!
Start with basics,
Fresh fuel?
Checked spark plug condition?
Checked for spark?
Tried cranking with a little throttle?
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  #30  
Old 27-02-2013
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Fresh fuel, plug is dry.

New pilot jet, new main jet.

Carby bowl had fuel, drained and tried again.

It was running before, wouldn't idle.

Took it apart, clean jets, would idle, but die on throttle application.

This time I took to it with the remainder of the jet kit. Including the accelerator pump bushing.

I might pop the idle jet back out and put the other 42 in. But I don't think it will make any difference.
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