DirtDemon

You should be fine on premium pump gas, just use good gas. I imagine that motor would be good on pump gas up to about 11.5:1 or so. Depending on how the engine is built, more modern motors can run up around 13:1 before you really need high octane fuel, that is pretty much the limit though, many people run race gas or a mix of race and pump gas at that point.

Welcome, nice Cat.

What is it for?

It sounds like a choke problem or your pilot circuit is way too rich, have you tried adjusting the pilot screw?

That must have been a pretty good hit to bend your axle like that, could have easily knocked you right off the quad, did you get some good hangtime?

I'm pretty sure I have tried to explain to you the idea of keeping your old thread going instead of starting a new one about the exact same thing. I'm not trying to be an as*, but I also don't like having to repeat myself. I moved your post into the old thread you started. PLEASE, don't start new threads unless you are jumping to a different subject. It cuts down on clutter in the forum and also gives people who might be trying to help a chance to read over the history of your issue and see what input others have offered, so it is to your benefit as well. Now, it is really tough to know what you may have missed, diagnosing a problem with so many possible causes is quite difficult to do without having the machine there to look over in person, so any little bit of info that you may have to add will be of great help. I think the most likely problem is that you may need to bore your cylinder and jump up to the next size larger piston. Some other things that come to my mind are; your vavles may be adjusted too tight, you may have some kind of damage to your cylinder wall, your cam timing is off. I know this has been a problem for you for quite some time, hopefully you can get that thing fixed. I know how disappointing it is to have a machine down. Good luck man.

If the battery isn't fully charged, the FI won't operate. The motor will crank, but it will not fire. I would start there, put the battery on a charger to make sure it is 100% charged and then try. I was told the battery needed to be put on a tender once a month to keep in in top shape to avoid that problem. I haven't done, it, nor have I had any problems, but I do know that the FI needs a certain amount of voltage to operate. You also might check your kill switch and attatched wiring, make sure all the ignition components are plugged in tight. The motor will still crank if the ignition is off. Good luck, I know how much of a pain it is to take the tank off.

Welcome, if you have any photos or video of the "Airfarm" we would love to see them.

Good stuff, nice bump you got there.

Muddslutt, nice handle, welcome aboard.

Also, be careful with the tranny, you don't want the gears coming off the shafts, it is a real pain to figure out what goes where if things come apart. I have learned that one the hard way.

So true, the case spitting tool makes things much easier. They are expensive though, I priced one for my CR 500 motor, and the thing was like $180 if I remember correctly. I just made my own, I make alot of my own specialty tools. Here is the one I made, alot of money can be saved with a welder and cutting tools.

Are you saying that fuel is entering the vacuum hose when you hook it up? Sounds like you have a bad petcock. Since you say it runs fine without the vacuum line attatched, it seems like the easiest thing to do would be to install a manual fuel valve in place of the vacuum operated petcock, and block of the vacuum line. Or you could just get a new petcock, but they are expensive. I believe there are models of that machine in the same year that use a regular manual style petcock.

They're right, it is FI. That opens up a whole lot more potential problems. Could still be related to an air leak, or valves being out of adjustment, but there are several sensors that could be causing your problem too. First, make sure everything is plugged in tight, and check the sensor in the airbox, it is a temp sensor, make sure it is clean. There is a thottle position sensor on the side, that could be giving you problems, there is also an air pressure sensor that connects to the throttle body via a hose, I wouldn't rule that out either.

I imagine the cam profile is less aggressive, if a cam from an older model fits that may help you gain a little power. I would imagine that the jetting was leaned out for the tighter EPA regs too. Might look into intake changes, the newer design may be more restrictive than the old one. They probably made changes to the timing curve too, if an older CDI box will work, that would probably help wake it up too.

The size of wrench you use is the one that fits, could be anywhere between a 12mm and a 19mm, maybe bigger, maybe smaller, but the one that fits is the one you need. Does the bolt head look damaged?

That's a bummer right there, the old back feeling any better yet? Love the rope-tie-rod, very MacGyverish.

Figure anything out?

Good luck, hope you get it figured out. Electrical issues can definately snowball, and spread around making it difficult to find exactly where the problem is.

Your thinking isn't off base there Predrider, I was thinking that a pilot screw adjustment might help, or you may need to adjust your valves. Is it ever hard to start? I don't know of any EFI kits are out there, but if there are, I would bet they are extremely spendy.

Back to the topic at hand here, I would tend to agree with all the advice that has been put out here, could be rings, could be work valve guides or seals, could just be that there is too much oil in the motor, or the oil is too thin or the wrong type. Have you figured anything out yet?

I would just try to get ahold of the original carb, a used one in good shape can be gotten for a decent price, a new carb will cost a few hundred bucks. Just make sure you only buy from a seller that has a good rep, that way you will be less likely to get a crap part. If you want to know if this particular carb will be compatable, you might call someone at Mikuni, or some place like Sudco that does carbs.

Weak battery might be why it wont start with the electric start. How did you check the timing? How did you come to the conclusion that you had a bad stator? A bad coil or pulsar coil coul be causing you problems, I would test those and make sure they are good.

Oil smoke will look different depending on how much oil is being burnt. A little oil usually shows blue smoke, if you are burning alot of oil, and it sounds like you are, it will burn white and smell very strong. Could be piston/rings, could be worn valve guides/seals, could be both. I wouln't worry about the jetting until you get the motor fixed, if you mess with the jetting now, you will probably have to change it again when you get the motor running right. But generally you need to jet just a bit richer for a high flow air filter.

How and where is it bent, post a picture. I fixed a bent frame problem on my LT-R by cutting off the a-arm mount and moving it out so it would line up with the other mounts and straighten my a-arm back out. Alot of things can be fixed by cutting and welding. I realize this isn't an option for everyone, but if you have the recources, or know someone who can fab metal, you might be able to get out of this one a little cheaper than you think.