vmaxup Posted February 7, 2004 Report Share Posted February 7, 2004 ok I read the guy who had some backfire problems. I dont know if he fixed it but here is my problem. Ill tell you the whole story. And what ever the response is dont tell me i have bad fuel. or to clean my carbs. my mods are pipes, K&N,airbox cover removed,torus diconnected, twist throttle, idle screws,ebrake removed and wiring. I was at Glamis for Halloween road the first day great. Plugs were cinimon brown. 2nd day while riding I herd a small pop once and a while. I stoped and checked my plugs to see if I was runing lean. Cinimon brown still. rode back to camp found out the boost bottle ripped a boot on the left side. Ok so new boots and it still backfires. So I put bigger jets in and cleaned the carbs like all day tried everything. got madd and road it anyway. We wont get into the crash and burn in a witches eye that night. Anyway.Got home and tried a bunch of stuff. So finally I figured I must have a stuck ring. So I pulled the cylinders off no stuck ring. So I replaced the rings. Did an air leak down test. It held 5 pounds for a hlf hr.So I start it up and it still dose it. I let it run idleing for a while and would crack the throttle. Then one time I cracked the throttle and the crank let loose. Same side as the riped boot. S o I figure that rodd was getting ready to go and that was my problem. Noddaaaaaaaaaaa! Rebuilt crank,New seals gaskets,milled the head and since the guy was boring it . he ported it. You know if it dont run maybe going faster will help.so 1grand later and all fixe right Naddaaaaaaaa! So last night we got the new motor together and installed it in like 3 hrs. Record time! At 10:30 at night I was ripping up and down the street to try it out. Ran great and that porting really works great.Really fast. So all fixed right Nadaaaaa!! Got out of work early Fr. Decided to put some new brakes on the old work truck.Then thought I would rip around on the shee again. Hard time starting now. Then its back to backfire. It was like theres an elf in the garage when i leave the house. Ok so i find out after swaping carbs from another banshee and pulled my silencers apart to see if there clogged there not. That a plug is bad, I put in a new plug and off we go. I get back and start adjusting my idle screws and noticed were back to running on one cylinder other side now. Only one pipe is hot. I check for spark on and another bad plug on the other side. Sso I dig around in some old jet ski stuff and find a Br8es and a B8es. Cleaned them up and threw them in. All good runs great. Then backfire is back again damn elf. So anyone have an answer. It cant just be plugs fom the start at Glamis. why is it good than bad. Why am I now fowling plugs all the time. There a nice cinnimon brown. It cant be the Carbs tried two sets. It has to be electrical. I think? Stator bad? Coil Bad? cdi Bad? I give up! Ive never fowled ouut a plug on a banshee of even herd of anyone else fowling a plug on one.. 4 stroke looks pretty good about now. Leaving for Glamis in 4 days help. And no the air in the tires is fine Quote Link to comment Share on other sites More sharing options...
CRANKINPEDRO32 Posted February 7, 2004 Report Share Posted February 7, 2004 make sure the electical outlets are connected right, i have seen a banshee where when the keyswitch is not turned on, it back fires but still starts. once the key is turned on, it runs like a dream. Quote Link to comment Share on other sites More sharing options...
FORMULASPEED Posted February 7, 2004 Report Share Posted February 7, 2004 Is it a backfire pop or more like a hiccup with a rush of air? Quote Link to comment Share on other sites More sharing options...
frocashmoney24 Posted February 7, 2004 Report Share Posted February 7, 2004 well the reason ur plugs are fouling is the jetting is off, sounds to me that you mihgt have a bad reed or a clogged jet Quote Link to comment Share on other sites More sharing options...
vmaxup Posted February 8, 2004 Author Report Share Posted February 8, 2004 it runs really strong. But I think it has too be electrical. Wwhen it is idling you can hear one cylinder not firing at times then its back again or it will foul the plug out. Quote Link to comment Share on other sites More sharing options...
vmaxup Posted February 8, 2004 Author Report Share Posted February 8, 2004 ok new news on this problem. I put a different stator from the donor banshee and it still pops when your on the throttle. Almost like its lean but its not. ok so i herd reeds a couple of times. I do remember the boysen reeds were alitttle open but not bad. Do they have to be totally closed and would this cause the problem. Can I flip them no new ones at the parts store and im running out of time for the Glamis trip. I supose i could go and get a 7000.00 4 stoke but that would suck and spent all my money on this thing so help if you can. Quote Link to comment Share on other sites More sharing options...
dunegoony Posted February 8, 2004 Report Share Posted February 8, 2004 Look at your reeds, if they arent broke, flip em upside down. Second, check both your plugs and stator pickup and make sure both are gapped at .018"....not a smig more. I know that's tight, but if youve got a bad coil (which will act up once it gets hot) the tighter gap will help. Try that and let us all know. Quote Link to comment Share on other sites More sharing options...
vmaxup Posted February 8, 2004 Author Report Share Posted February 8, 2004 so you think my coil is going down? I thought when they go bad there no good and wont even work? Ok its 8:20 and on my way home to grab a cold one and a wrench and get at it. Youu are right though it idles fine but when it warms up it pops. Anyone else got some info? Quote Link to comment Share on other sites More sharing options...
SDD Posted February 8, 2004 Report Share Posted February 8, 2004 Take and swap the spark plug wires... put the right one on the left and the left on the right. If this causes the misfire to happen on the other side a plug wire is bad. 75% of the time it's a plugged up pilot jet... I don't care how much you try to force air through or carb cleaner it doesn't matter. You need to stick a very fine piece of wire through the pilot jet to get what ever is plugging it up out. If this doesn't help you should look at adjusting the air screws on both carbs so they are out the same amount. Quote Link to comment Share on other sites More sharing options...
vmaxup Posted February 8, 2004 Author Report Share Posted February 8, 2004 ok but if you read the entire story i said i tried some carbs off another banshee so there goes your dirty carb. Not so dirty is it? SO here is my list of things new and things checked. New crank Rebore and weisco pistons 30 over Carbs cleaned and float level set idle screws at 1 1/2 270 mains at 5000 ft replaced stator assembly checked silencers and pipe from being clogged new plugs key works stop switch works reeds not broken slids in carbs in sinc little black tube is there COOMON GUYS You people talk so much about stroker cranks milled heads pipes and what color should I paint my frame. Who gives a crap what color your frame is or weather you can get your gold color of your rims. I need some answers to the problem. It seem latey no one on this sight really reads the problem. and the most comon answer is it must be your jetting. Now listen to that answer.Call NASA your the winner. You can figure out the space shuttle doors.Yaa! If it was my jetting or my Carbs are dirty then why do the carbs off another Banshee that runs great do the same thing???????????????????????????????????????????????????? hello Nasa anyone. Oh no I found the problem my air pressure was wrong on the frnt left tire. At this rate I should just find a paddle for the VMAX and run her at Glamis Dig deep someone??? When I do find it I will let you all know what it is and it wont be my air pressure Quote Link to comment Share on other sites More sharing options...
SyNtAxx Posted February 8, 2004 Report Share Posted February 8, 2004 Hey all, I had a VERY similar problem. I checked everything, reeds, carbs, jets,coil cdi,and stator. i used a mutil-meter on all the parts that i could get a reading from and they were all in spec. HOWEVER...it turned out to be my stator and here is what happend...while it was cold it would run perfect until the engine warmed up and thus the stator....once the stator warmed and expanded one of the green wires on there would expand with it thus causing a short and the popping and cutting in and out.....the epoxy that holds some of the wires down get brittle with time and cuases shorts in the current... I replaced my stator with a brand new 200 watt job and problem was immediatly solved.... Just my experience..... Nick Quote Link to comment Share on other sites More sharing options...
fixitrod Posted February 8, 2004 Report Share Posted February 8, 2004 Okay, I know these are very basic, but here goes. Maybe, if at all possible, try a different cdi or coil. If it's happening only when it's warm, it could be something flaking in the cdi. That's my guess if your reed are in good shape. Have you eliminated the tors and parking break circuit. Maybe it's something very silly to do with them. Quote Link to comment Share on other sites More sharing options...
Holyman Posted February 8, 2004 Report Share Posted February 8, 2004 I'm going to say stator or flywheel or timing plate. The only thing that hasn't been swapped out is the timing plate and the flywheel. Make sure the rivets in the flywheel are tight, the magnets are not loose, the key and key ways are in good condition and the timing plate is not loose. Try adjusting the timing a little if your plate is modified. You also need to make sure you're getting gas from the gas tank. Pull thetank valve and make sure the screens are clean inside the tank. Quote Link to comment Share on other sites More sharing options...
vmaxup Posted February 8, 2004 Author Report Share Posted February 8, 2004 ok call Nasa There having problems with the bay doors. Now how can it be the stator if Iswaped it with a running banshee and it still did it. THIS WHAT IM TAALKING ABOUT RREAAD TTHEE POSST AAND THINK WHAT YOUR SAYING!!!!!!!!!!!! OH yes its the TORS I think I already wrote its FUCken GONEE man unless the elf put on when i wasnt looking. SO me myself thinksits the Coil. going to swap it tomorrow and we will see. You guys are still giving the answers like its my air pressure is wrong. READ BEFORE YOU ANSWER Now Holloman You gave a good one like the fuel screens were are they do I just take the pet cocck out? Quote Link to comment Share on other sites More sharing options...
SyNtAxx Posted February 8, 2004 Report Share Posted February 8, 2004 Hey, Read this dickhead...... How can a stator be bad when I tested it and it was with in spec? Mine tested fine and it was still no good. If you think you know it all or cant take suggestion then dont ask for help. Nick Quote Link to comment Share on other sites More sharing options...
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