Yeah fix the exhaust leak ! << Reason it,s poppin out the exhaust it,s suckin air intoo the exhaust C02 and oxygen combined with heat goes > Pop ! If it pop,s back thru carb this is timming or intake leak ? im bettin it,s exhaust tho under a load between shiftin gear,s etc fix exhaust leak ! now as for timming 28 degrees total advance at 3000 RPM will work But it,s better too understand it especially with a double 009 dizzy ? a better setting here is 28 ta 32 degrees total advance at 3500 rpm . The 3500 rpm being where a fairly stocked or mild cammed motor will plain out when reved << Kinda sounds like 4 th gear at 70 mph runnin down the road if ya play with the throttle you can learn where 3500 rpm is at cause motor plain,s out ? If not ? go get a Tachometer and play with it till ya learn where it,s at ? now 32 degrees on your degree pulley << Degree pulley is a must here . << Is the maximum advance any more than 32 degrees will cause motor too run hot and result in premature engine failure ? But 32 degrees is optimum and sought after but as the bushing,s in the dizzy wear it,s regularly referd too as 28 ta 32 degrees so i like 30 degrees 31 maybe with your pertronix ignition should be less fluctuation especially ifn the dizzy is fairly new might get 32 but fluctuation included no more than 32 degrees total advance ever ? No less than 28 degrees ever << Fluctuation included here ? Now that i xplained fluctuation here at 3500 rpm on degree pulley you can see how too figure out if your 009 dizzy is not workin properly or worn slapp out . Or even possibly with a cheap degree pulley that it might be workin back and forth on wood ruff key on the crank << Some what common problem with Tai Wann Degree pulley,s somethin ta look out for ? Now on valves adjustment too tight is worse than too loose ! Sett all valves at 006 thousandths both exhaust and intake << Note i really dont give a hoot what book say,s , or the buggy mech down street say,s etc set um .006 with fresh feeler preferably one hasnt had adjuster turned down on it bendin it all up or gouged out, or worn down too .004 thousandths etc . alway,s start with number 1 cylinder adjust both valves ? break all the valve adjuster,s loose even the ones that feel good like there adjusted etc. << Re-adjust um any how . Now when adjusting them what ya want here is too with your fingers tighten the adjuster screw down on feeler gauge till gauge wont move ? << fingers only or it will bend crease fold spindilate the feeler gauge etc but till gauge wont slipp back and forth then back adjusting screw off till there is just a slight dragg on the gauge tighten lock nut re- check the slight dragg on gauge . <<< May take few try,s ta gett it perfect but perfection is required here . adjust both valves on number 1 at TDC compression stroke then turn motor counter clock wise 180 degrees too the 0 on degree pulley adjust number 2 cyl valves then turn counter clock wise too number 3 cyl back too TDC mark on degree pulley etc etc . Note i usually remove Dizzy capp and where the rotor points too number of cylinder im adjusting work,s as a good visual aide . Sean
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