im having trouble with my 87 quadzilla its hard as hell to start and occasionally backfires and kicks back HARD. Ive got a lrd adjustable pipe and silencer on it v force3 reeds with reed spacer using vp 110 fuel with klotz oil im just kinda curious as to weather its jetting timing or electrical problems it will start easilly with a tow in 5th gear

timing marks are all good on stator and balance gear pilot jet is the stock 30 air fuel at 1.5 turns needle in middle clip as far as slide hight im unsure on that one

will your zilla idle after you pull start?

Also, 22.5 is the stock pilot.

Try setting your slide height first.  First let out all the slack in the throttle cable by adjusting it at the handle bars.  Basically, there needs to be slack in the throttle cable so when you lower the slide height, the slide will actually go with it.  You have to remove the tube between airbox and the carb.  looking into the carb, adjust the thumb screw - big screw with a spring on it - out until the slide is all the way down.  from there, raise the slide about 3mm.   adjust the throttle cable at the handlebars so that there is no slack and the slide moves as soon as you press the thumb throttle.  Then never touch the thumb screw again. 

Any idle adjustments from here need to be made with the air/fuel screw.  I usually do 1/4 turns at a time so i can keep up with how my turns out i am.

you didnt mention what air filter or if you are running without the airbox lid.  But, assuming you are running a K&N or UNI without the lid,  by guess a 27.5 pilot will be the max.  Most likey a 25 but always start rich and work your way down. 

Also, i don't know if you're familiar with the zilla start procedure but from a cold start,  turn the ignition off and moderately kick through about 3 times to prime the motor.  On the next kick, turn ignition on, set the piston at TDC and kick it like it owes you money from the top of the crank.  If you dont know how to tell if it's at TDC, slowly push the kicker down until it feels like it sets in a notch.  that will be TDC.

I know it seems like a lot of work but if you use this procedure and your zilla is jetted correctly, it will start 1-3 kicks every time.

well its got a twin air  filter 30 pilot jet lid removed and yes i know tow starting is hillbilly but it works when ur in a pinch and that bastard kicker has  already damn near broke ur ankle and made u teer up

thanks for the info on carb setup and start procedure

I've heard nothing but bad about the pvl for the zilla's.  Maybe someone who has used them on a 500 can chime in about their experience before you purchase one

The shape of the PVL ignition timing curve is not right for the LT500.  The PVL will blow your foot off trying to kick start the engine. 

The small light-weight PVL flywheel is hard on transmissions, chains and clutches

They are money pits.  But once you fix all the factory flaws they're really great reliable bikes.