I'm running motoplat mini flywheel ignition, 88.5mm bore, ported, 38mm Mikuni flatslide 280 main havent looked at pilot yet, B9es plug, v3 reeds with the stuffer, home made exhaust to fit LTR frame and im having issues. Whats the ideal ignition timing using the motoplat first off? Also just rerplaced waterpump and upon cranking it shot something through the small cover, this ever happen? According to most jetting posted on here im bad lean but plug is saying little rich. Open carb at the moment, no filter. Runs like crap spitting and sputtering but will rev half way decent, no hacking. What are some things to look for and do> Will reed stuffer benefit or hurt it for motocross? I need to get a stock ignition so i can set it right with it then play with the motoplat so i can elimate that hassle right now but if someone can point me in the right direction of tuning this motoplat i can manage it. What would be the best carb for motocross i have quite a few lectrons mikunis and keheins. Open to all suggestions on engine setup please get me going in the right direction, Also can you put the 87 and newer 250's 6 speed tranny in the 500?  Thank you.

If you set your ignition to tdc it should run. I agree to go back to stock ignition system. I believe the 89 up had a closer ratio trans and thats about it for upgrades. A bored stoke carb runs pretty good on the 500. Piranha Pete does a good job boring them out. He did mine.

No on the tranny question I already asked that when I found out the Zilla only had a 5 speed. What's a reed stuffer? Do you mean spacer?

The stuffers are the ears that protrude into the reed cage if you are running a stock reed boot. Guys cut them off when they upgrade to V-Force reeds.

Quote from: Cartee#2 on January 18, 2014, 04:53:24 pm

I'm running motoplat mini flywheel ignition, 88.5mm bore, ported, 38mm Mikuni flatslide 280 main havent looked at pilot yet, B9es plug, v3 reeds with the stuffer, home made exhaust to fit LTR frame and im having issues. Whats the ideal ignition timing using the motoplat first off? Also just rerplaced waterpump and upon cranking it shot something through the small cover, this ever happen? According to most jetting posted on here im bad lean but plug is saying little rich. Open carb at the moment, no filter. Runs like crap spitting and sputtering but will rev half way decent, no hacking. What are some things to look for and do> Will reed stuffer benefit or hurt it for motocross? I need to get a stock ignition so i can set it right with it then play with the motoplat so i can elimate that hassle right now but if someone can point me in the right direction of tuning this motoplat i can manage it. What would be the best carb for motocross i have quite a few lectrons mikunis and keheins. Open to all suggestions on engine setup please get me going in the right direction, Also can you put the 87 and newer 250's 6 speed tranny in the 500?  Thank you.

The water pump cover hole came from the screw holding the impeller in place.  It must have gotten loose and poked a hole after you started it up.

This happened to me. That impeller retaining bolt gets loctite.

Correct on the hole I'm missing my new lefty bolt lol. Motoplaat is good and it's lean on very bottom and top. They say 2.2mm before TDC on dial indicator and i was set at 2mm flush and breaking kickstarters. It's at about 1.3mm before TDC now and is much friendlier but I do want a stock one for initial tuning then swap to the motoplat after it's dialed in with stock. Good step in the right direction thanks guys.