Ap-timing


4 replies to this topic
  • Lorre79

Posted January 12, 2009 - 02:42 PM

#1

Did O-ring mod, standard jettings with aftermarket exhaust but still bogging.
New YZF 450 2008

  • Wes Woodin

Posted January 12, 2009 - 07:56 PM

#2

Did O-ring mod, standard jettings with aftermarket exhaust but still bogging.
New YZF 450 2008

what gas are you running, elevation,main jet, ect.

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  • Lorre79

Posted January 13, 2009 - 12:44 AM

#3

-Octane 98 Gas right from the gasstation
-Main jet 160
-Pilot jet 45
-standard needle; Nfpr
-neelde pos: 3rd.


Heigt is around 30M in whole belgium, i think this is equel to sea level.
Put a splitstream in carb, and a bigger carburator sump.
There is a HGS aftermarket exhaust installed


Should I try to measure the AP-timing, should I change te leak?

:thumbsup:

  • Wes Woodin

Posted January 13, 2009 - 07:44 PM

#4

-Octane 98 Gas right from the gasstation
-Main jet 160
-Pilot jet 45
-standard needle; Nfpr
-neelde pos: 3rd.


Heigt is around 30M in whole belgium, i think this is equel to sea level.
Put a splitstream in carb, and a bigger carburator sump.
There is a HGS aftermarket exhaust installed


Should I try to measure the AP-timing, should I change te leak?

:thumbsup:

Hey! What you encountering is a lack of gas when the throttle is opened up. The ap pump squirts gas into the engine when you crack the throttle but when there is not enough gas, the engine is flooded with too much air. You have to get more gas to the carb when the throttle is opened. To do this you can o ring or wire the cam, called the ap mod, as well as, I think the most important, richen the leak jet. The standard leak jet is #55 in an 08 yz450f. You need to go with a #45. This will in conjunction with the ap wiring produce a longer stronger squirt from the AP, thus eliminating the bog. I installed the R&D powerbowl. The reason I installed the R&D is it offers an adjustable leak jet. I really believe you shouls go with a #45 leakjet. I hope this helps. Wes

  • Lorre79

Posted January 14, 2009 - 01:42 AM

#5

Thanx, i am going to try with a 45. leakjet.
and also richen up de pilot.

Greetz





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