pinkshee Posted March 5, 2009 Report Share Posted March 5, 2009 ok i just rebuilt the top end with vito's pistons std bore, 2 stage carbon fiber reeds and pro circuit exhaust. i put a fresh stock head and crank in also. it has a +4 key in and my jetting is 280, 25, 3rd clip, and 2 and quarter turns out on the air screw. ele is about 100 ft above. new plugs and cleaned the air filter. running 93 with octane booster at 32:1. and 130psi in both cylinders. And yes i searched first. Now with that said here is the problem. I have Fuel, Spark, Air and Compression (everything required for combustion if i remember correctly) but guess what...... nothing. i tried pop starting it and it only popped a little bit and backfired a couple of times. the head got a little warm but not the pipes. i am dumbfounded. the plugs are wet and black in both cylinders, obviously because the motor isn't firing.... right? While i am writing this it ran across my mind that if the timing key was installed backwards may be that could be the reason it is acting retarded (pun intended). Btw i put the key in with the "ledge" on the forward side of the crank (in the direction of rotation). thanks in advance. Quote Link to comment Share on other sites More sharing options...
shee4speed Posted March 5, 2009 Report Share Posted March 5, 2009 you running stock carbs with tors still? You have the choke tube installed? Quote Link to comment Share on other sites More sharing options...
pinned247 Posted March 5, 2009 Report Share Posted March 5, 2009 Try giving the carbs a few taps with the handle of a screw driver or something. You might have a float or something stuck in there. That happened to me. I put everything back together. I had everything required to start it and nothing....gave the carbs a few taps and shee fired right up. You may not be having the same problem...but hopefully that's all it takes. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted March 5, 2009 Report Share Posted March 5, 2009 Why octane booster?What did you use to seal your cases?did you do a pressure test on the motor?What do you mean by a fresh stock head?Did you try swapping the key around(i never saw one)?Are your carb slides in rite? Just some thoghts Quote Link to comment Share on other sites More sharing options...
tony cub Posted March 5, 2009 Report Share Posted March 5, 2009 leak down???? Quote Link to comment Share on other sites More sharing options...
AKheathen Posted March 5, 2009 Report Share Posted March 5, 2009 turn the airscrews back in to 1.5, and clean/sync your carbs. don't forget the little choke jet in the bowl. i'm assuming your choke trasfer tube is on. what is your compression and altitude? Quote Link to comment Share on other sites More sharing options...
pinkshee Posted March 5, 2009 Author Report Share Posted March 5, 2009 the tors is removed and the choke tube is installed. i also tried tapping the bowls with the a screwdriver thinking the floats might be sticking... still nothing. i am using octane booster because any octane over 93 is not readily available to me and i required higher octane for the old head which was shaved(also why i refer to the new one as fresh since it is not milled) i haven't tried swapping the key around yet but i plan to this evening and the carb slides are in the right way and the carbs are sync'd. haven't done a leak down test but i will look into it and i used high temp copper rtv to seal the case. while i am at it i will go ahead and pull the carbs and clean them. i am really hoping that the timing key is just backwards. thanks guys. any other thoughts. Quote Link to comment Share on other sites More sharing options...
hercalmighty Posted March 5, 2009 Report Share Posted March 5, 2009 How bout your pick-up gap? Did you happen to check that? Quote Link to comment Share on other sites More sharing options...
pinkshee Posted March 6, 2009 Author Report Share Posted March 6, 2009 ok i flipped the timing key around and now it sounds like it wants to fire but it won't. the pickup gap is set at .24 because with my previous set up that is the only setting at which it would fire. i am going to reset the pickup gap to .20. hopefully i can get it running this weekend because i am having withdrawals. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted March 6, 2009 Report Share Posted March 6, 2009 ok i flipped the timing key around and now it sounds like it wants to fire but it won't. the pickup gap is set at .24 because with my previous set up that is the only setting at which it would fire. i am going to reset the pickup gap to .20. hopefully i can get it running this weekend because i am having withdrawals. was that you a while back with the weird pickup setting thread, which never was solved? Quote Link to comment Share on other sites More sharing options...
pinkshee Posted March 6, 2009 Author Report Share Posted March 6, 2009 yeah that was me. never figured it out just went with what worked. so i guess my next step is going to be resetting the gap to .20.i have been thinking about jetting also. the vito's pistons and reeds say to rejet but i haven't had it running yet to do any real diagnosing. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted March 6, 2009 Report Share Posted March 6, 2009 i would see if someone around you has a cdi you can test out, too. it could've shit the capacitors while you were rebuilding :shrug: Quote Link to comment Share on other sites More sharing options...
blaster2006 Posted March 6, 2009 Report Share Posted March 6, 2009 you have a few mods, and you are running leaner than stock on the airscrew. turn that airscrew in 1 complete turn. so its 1 and a quarter turns out. and if you have some kind of aftermarket filter.. turn it in 1 and a half turns more from that it is now so its only 3/4 turns out. Quote Link to comment Share on other sites More sharing options...
2001Stroker Posted March 6, 2009 Report Share Posted March 6, 2009 Do you still have the stock timing key? Maybe put that in and try iy. Carb slides in right? I would put it on top dead center, and make sure the trigger is crossing the pickup in the right spot. I don't know how it would have gotten off, but I would check it. Is it possible that the new crank has the keyway slot machined in the wrong spot? Quote Link to comment Share on other sites More sharing options...
AKheathen Posted March 6, 2009 Report Share Posted March 6, 2009 you have a few mods, and you are running leaner than stock on the airscrew. turn that airscrew in 1 complete turn. so its 1 and a quarter turns out. and if you have some kind of aftermarket filter.. turn it in 1 and a half turns more from that it is now so its only 3/4 turns out. if your runnig the rpm's high enough in the airscrew range to be effected by filter mods, it's time to shift, or get in it already Quote Link to comment Share on other sites More sharing options...
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