fastbanshee8

Riding an ATV without a filter, is a good way, to ruin a motor. You will be really lucky, if your top end isn't destroyed. I hate to say this, but what you did, was plain stupid. If everything is clean, carb wise, and it still won't start, do a compression check. If it's 100 lbs. or below, then rebuild the top end. Low compression will make them very hard, if not impossible to start.

A top end rebuild, I.E., new pistons, new rings, new gaskets, and maybe even boring it. If it's not ported, the time to do it, is when you have to rebuild the top end.

I forgot, that you will probably need a real good clutch also. The head is cut in the dome area, because the piston will actually be 2mm above the top of your cylinder, at TDC. With the parts you have already, and the swinger you are thinking about, you should be in good shape, other than crank, pistons, porting, and head work.

If you have stock cylinders, you will have to have the head cut for a 4mil, regardless of the type of head, unless you want to run a spacer plate. To make the 4mil work good, you will need porting, bigger carbs, pipes, maybe a longer swinger. It's going to take some money, to make the 4mil work good. :biggrin:

The CPI's will hit the carbs even more. I used to run FMF Fatty's, and my FMF's hit the 34mm Mikuni's, but just barely. Now I have CPI's, and the CPI's hit the carbs worse than the FMF's did. I ended up having to put some spacers between the frame, and the pipe mounts, to gain a little bit of clearance.

Backfiring is a sign, that it's lean. Maybe an air leak, or just too small of jets, or maybe even your fuel flow is restricted some where. You need to find out what the problem is, before going riding again, or you may end up rebuilding the top end.

I've had numerous pipe springs break in the last 11 years, stock springs, and aftermarket springs. I lost one in April, at the dunes.

It can have everything to do with the right crank seal, because that's what keeps the gear oil out of the motor. Evidently you haven't had a Banshee lower end apart, or you would know this. The cases meet, at the middle of both crank seals. Trans fluid getting into the crankcase, will cause the right side to smoke really bad, plus it will smell a lot different.

That hose is the vent hose for the transmission, and it hooks into a plastic tee above the carbs, or at least mine does. It vents excess pressure, when things start heating up inside the case, and it will leak trans fluid, if the trans is over filled.

Running a 4mm stroker with stock ports is going to defeat the purpose of getting a stroker crank to begin with. If you are still running stock cylinders, then maybe a little port work would be better for you, before the stroker crank mods, unless you plan on doing it all at once. A stroker adds more torque, and HP. You will gain a little with stock ports, but you're going to be leaving a lot of torque and HP untapped, because of the lack of porting for the 4mm stroker crank. If you want to know what all is involved with the porting, then you need to call one of the builders that do the port work, but don't be surprised, if you don't get told everything. Port work isn't a "simple job", that anyone can do, and it takes some specialized tools. It's expensive, and time consuming. Jeff at FAST Racing would be one to call, and talk to about the porting ?'s.

I got mine from White Brothers, and I think it was a Moose stator, and it's 275 watts. I've never had a problem with it, and it's been on for 5+ years. I got it at cost, plus shipping, which was around $200.

The airbox boots will fit, but you will have to stretch them a little. Also, when I had 28's on mine, I found out that cutting about 3/8"-1/2" off of the plastic tubes going into the airbox, made installing, and removing the carbs much easier. Just leave enough of the plastic tube, to get the boots clamped on good, and secure.

Hell, I even put a pancake bearing in mine, and it still does it. I'm not worried about it, until the clutch won't disengage at all.

The same thing is happening to mine, with the FAST clutch in it. It works fine everywhere else, so I just put it in neutral to start it, and I don't worry about it sticking when cold.

Powdercoat will outlast chrome, and be a lot easier to take care of. A friend of mine takes the stock rear axles, and has a machine shop turn them down enough to remove the gold color, so that the axle has an almost chrome look, and then has it clear coated with PC. Chrome tends to rust, if not taken care of really well, and PC just needs to be hosed off, and wiped dry.

Other than rejetting, and changing the choke controls, there aren't any other mods, that you will need to do to the carbs, to run them. You will have to get new intakes for the 34mm carbs, and air filters. A friend of mine, used to work for the local Polaris dealership, and he also did the porting on my cylinders, and he told me about the Polaris carbs years ago. For $20 bucks a piece, that's a steal. :thumbsup:

I would highly recommend it, because when riding, the bearing carrier gets hot, and if you go through any kind of water, that's over your axle, it will cause the water to be drawn in past the seals. I know, because it happened to me years ago, and it ruined the bearings pretty quickly from rust. The extra grease in the carrier will help keep the water out, plus by removing the inner seals on each bearing, they will always be lubed, unless you run completely out of grease in the carrier. I've had the grease zerk in my carrier for almost 10 years now, and the bearings are still in good shape.

The bolt in the cylinder walls, is to drain the coolant. To get the air out of the system, I just fill it up, and let it idle for a little while, with the radiator cap off, and that seems to do the trick. Don't fill the radiator all the way up with coolant, or some of it will come out, when the air pockets come to the surface.

My CPI's tend to expel more oil out the silencers, than my FMF's did, and I don't know why. Maybe it's just the nature of the beast. Mine don't leak at the motor-o-ring coupling, but I did put new o-rings in, and I'm still running stock cylinders.

If the temps where he's located have been anything like the ones around here, you can have a 30 degree temp variation in one week, which will affect the jetting. Seems like the cheap pre-mix, and the other symptoms are just a coincidence. Don't rule out anything, until you check it throughly.

My engine seal kit didn't have the impellar seal in it, so I had to order the bearing, and seal seperate.

Since you're replacing the impellar, you might as well go ahead, and replace the impellar bearing, and seal, while you have it down that far. If you don't, and they fail, you will end up replacing both gaskets, the seal, the bearing, and probably the impellar, and maybe a few other things.

Were the temps cooler, when it was running right? If your plugs are wet, then you are too rich. Plugs don't foul from being jetted right on, or lean, just rich. I had the same problem, with my new motor, and I didn't realize how far off the jetting was, until I went to the dunes. I fouled three sets of plugs, getting it jetted right. It would run okay with a new set, for about 6 hours, then it would fall on it's face, and wouldn't rev for shit.

Since it revs fine, with no load on the motor (in neutral), and won't rev in gear, I would say that you are jetted too rich, providing that your air filters, and carbs are clean. It sounds like it's loading up, and it will only get worse, the hotter the temps get. Make sure both air mixture screws are set the same, both plugs are good, and both plug caps are good. If everything is fine, then go down a couple of sizes on your main jet, and see if that helps.