Mech

Ok. That's a much more informative explanation.. It does sound like carby, not the idle but possibly the needle or main jet, or float height, but before I went pulling it off again(since you sound like you know your stuff), I'd check the spark was a good one at the plug. If the plug cap comes off the lead, you could take that off and jury rig the wire on the plug for a while, a small split pin can be poked into the wire and fitted to the plug end perhaps. The other thing is, are you sure you have the right heat range plug for your riding conditions ? Have you tried one one step hotter ? Are you using NGK plugs ?

"Installed new battery. Now when trying to start, it seems normal, turns over, and begins to start, but immediately dies.". Well.. dying straight after start up, disregarding the battery issue, I'd be checking the fuel pump and pressure. Running lean could make it run hot. A burning out/seizing fuel pump could bugger the battery perhaps..

You need to drill a small hole in the brass plug(sounds like it's already been done) and screw a self tapping screw into it and use that to pull the plug out, then there is an adjusting screw under there. It would be unusual though for the idle mixture to foul a plug after 45 minutes operation. Does it idle ? Does the choke work, and turn off properly ?Are you sure it's fouling with petrol ? Does it smoke at all ?

Nah second hand observations about chinese bikes in general. CF aren't common here and I mainly work on suzuki and honda, a few yamahah and kawasaki, and very occasionally something american. My initial comments were about "chinese atv", and bikes.. of which there a lot of different makes. They really don't need any "talking down". Most of them are cheap and break parts far to easily as far as I can see, which is an opinion that sees the local bike shop owner, also a mechanic, refuse to even have them in the workshop. If you think Cf is the exception, and you're happy with yours, then that's fine. I hope you get a good run out of it.

Oh. Ok. There are a lot of makes of atv made in china.. Most of them break easy and parts are real hard to find. And when I say break, I mean things like kickstart shafts breaking, and gearbox shafts, things that should never break.. So it's CF that you want to know about specifically ? I wouldn't buy any of them, or a cf, but other people may chip in with opinions about CFMoto. Bottom line is probably that you get what you pay for.

Ha.. It happens ! Good onya.

And the shift in N-SL-1-2-3-4- Yes? And N-R ? So is it first or superlow it won't engage ? And does the lever move without doing anything, or does it come up solid against something so it won't shift ?

Have you read the owners manual.. some of the old models had a lock, you had to push a button or lever to get them into reverse and superlow,, It might be you aren't doing it right, or the lock is malfunctioning.. The owner manual might point you in the right direction.

It sounds to me like there is no choke plunger in there...

I think you already know the answer to your question.. But the real question isn't can you, but should you. I suspect you already know the answer to that too..

A service manual will tell you what it should have, and I'd highly recommend you use what's recommended, or something completely compatible.. Even the type of casing material they use to cast the parts can effect the antifreeze choice, then there's also the gasket materials and the sensors and radiator metals etc..

Drain the oil and use a magnet to find bit's of metal.. Flakes, chunks, dust.. It might be blown gears, but it might be something simpler, in the gearchange linkages.. inside the side case if you were lucky, rather than deep inside..haha.

I doubt the cdi is causing the problem. If the voltage doesn't rise when the engine is running then you need to diagnose the charging problem. You should download a service/workshop manual and follow the test procedure as written in the manual.. It could be as simple as a blown fuse or a broken wire.

Hi Charles. This problem has been discussed in her before, if you do a search for the symptom (one spark), you may find something useful. What I'd do though is check that all the feeds from the stator, and the trigger coil, are getting all the way to the cdi. You could check with the ohm meter or if you have one, use an old fashioned analouge voltage gauge, at the cdi. The cdi takes the voltage from the source coils and stacks the voltage up on top of one other to give a higher voltage, it could be that only one of those two source coils is getting through. It's possible that the cdi is counting source coil pulses and only triggering after it knows there has been two full rotations of the crank after a trigger pulse. If one source coil's not getting through it will throw the cdi's calculation off.

All I can tell is that it's a 2001 model. Digits 4-8 are the ones that describe the vehicle in most detail, but unfortunately they are left to the manufacturers discretion as to format. That make is not well supported and I can't find the details of how they code those digits. If you could find a dealer for them, and ask them, they can probably tell you.

If you have a timing light connect it and watch it to see if the spark dies before the engine stops rotating. Or, fit another sparkplug on the lead,and then rest the body of that sparkplug against the plug in the engine. If you have a good strong spark it will go through both plugs and you will be able to see the spark die on the test plug. Try it in a dark place.

So I'm not real familiar with yamaha, and their versions, but I just downloaded one manual(there are two there), and it shows the cdi as having an earth wire to kill it, and a 12 volt feed in only while it's cranking. That's to assist in easy starting, but the cdi should still spark without it. The ignition timing probably gets retarded by that 12 feed is all. Someone here might know otherwise about yamaha, but that's a common vehicle strategy. I'd disconnect the wires from stator to regulator down at the engine while I was checking the ignition system, just to be sure the regulator wasn't causing a problem. Then, if you disconnect the two single wires from the cdi(L/W + B/W), and plug in the stator plug at the engine and at the cdi, it should send a high voltage high current pulse of power out to the ignition coil when you pull it over. The cdi output is dangerous so don't get zapped by it. The coil needs to be a special low impedence one made for cdi ignitions. Cdi suitable ignition coils are everywhere these days and cheap. The book tells how to check them. The easiest way to check the cdi once you are sure the stator and tigger coil are good is to use a known good ignition coil.. Th cdi unit, and the ignition coil, the regulator, and the engine, all have to be grounded, together and to the frame. It might pay to check all those points where the earth wires connect are clean.

There's likely a manual in here.. up top click "downloads", then atv repair manuals, choose yamaha and scoll through for your model..

Good one. Glad to hear it. Long may it last.. haha.

Well as a mechanic I gotta say that is appalling ! That "replace everything" policy is the modern version of professional in the major part of the service industry. But they aren't competent..and they don't care they are incompetent, they charge anyway. And all those parts are what makes them profit, so why wouldn't they. If they admit fault, it costs them, if they bullshit and "justify" the necessity for all those parts, they get to charge you and make their wages, and profit on parts. If you have something like a small claims court, mediation process you can take them to.. I think you would have a very good case.. Did you get your old parts back ? Under these circumstances it should be standard practice for them to show them to you and offer them to you before they dump them. With or without the old parts, whether they were needed or not, they only did half the job and shouldn't have charged unless the job was done. They should have kept going and replaced/repaired the fault, then they can charge for their expertise. Grrr.. Anyway... I don't have a manual for that bike but I suspect the cdi runs off the stator, and/but needs a twelve volt feed into the cdi unit to turn it on. If you get a manual and follow the diagnostic steps(as a mechanic should do), it tells you how to test switches, and cdi units, and stators and trigger coils.. I think though that to eliminate wiring problems(because there are diodes in the wiring), you should do as you are suggesting, and hotwire the cdi unit as a first step, then worry about the electric start. If you look in a genuine yamaha pdf manual, in the ignition diagnostic section it will have a small wiring diagram of the ignition circuit I think, the bit's of wiring being used for the ignition will be highlighted, use that diagram and if it does show a 12 volt feed into the cdi, then do that, and check it's earth, and then there should be a spark when you pull it over by hand. If there is no spark then, with only the wiring from stator to cdi being used, it's either cdi(yeah I know, it's new), or coil, sparkplug, stator or trigger coi, or wiring.. The manual explains how to test the stator and trigger coil with a multimeter. That's the simplest test to do and it's not been mentioned.. Perhaps they were really certain about their ability to test a stator and so didn't think it was in question, or... they didn't check that.. In fact... if the wiring really is brand new, it's probably only going to be either the cdi or the stator.. So test the stator first, then if that and the trigger coil which is in the stator both have good readings on the gauge, try hot wiring the 12 volt into the cdi if it's meant to have a 12 volt feed, and test for spark while pulling it over.

It's probably got a bung on the left crankcase, facing forward, at about the eleven oclock position when looking from the side.

Ok.. Stuttering to a stop once hot, then restarting again a half hour later, is a fairly common symptom of a faulty crank or cam sensor in vehicles.. some makes/models it's a well known fault. Not saying it is your problem, but it would fit. That's the good thing about these forums generally, people have seen such things and we hear if they are common faults to the vehicle. You said one of the trouble codes was crank, so what were the others ? It's a good idea to note the existing codes, clear the record and restart and run the bike, then see what new codes you get.. Blocked fuel tank breather.. dirty fuel filter.. vacuum hose loose or holed.. These could cause it.. It's good to consider the circumstances as well as the symptoms.. So, is it time perhaps rather than temperature that causes it ? Does it always happen after some particular operator input ? It's always a good idea to pinpoint exactly, what circumstance induces the problem every time, then you generally get led to the faulty component or adjustment, and, you can test your repair with some certainty/confidence...

Ha.. my bad eyes.. I'm not familiar with those bikes but it's common in lots of auto software that a trouble code will set for crank position sensor if the crank kicks backwards because of either a bad startup attempt or because the crank got rotated backwards via the driveline. The code is just an indicator of where to look. And gauges vary by some percentage right from new, even the best of them, then with age they can get out by even more, so the readings of the sensors needs to be taken as an indication too. If the readings are close to the manuals recommended, but steady, I generally figure they are ok. Some software will decide there is a crank position(or cam position) problem, if either of the two readings get too far out of the expected positions.. as can be caused by worn cam chains or slippers.

Something on the bike might be shorting the CPS signal. Could be the wiring, you could wriggle wires with it idling listening for a missfire, and look for chafing, or it could be electronic. Or, use an ohm gauge where the CPS connects, and check for shorts to earth, or low impedence going into the control unit.The manual will tell you what to check next.. before you buy parts... That figure of 46v +- .003 though, sounds a bit strange.. 4 point six would be a common sort of voltage for something like that, ad then point 003 + or - might be correct, but point 003 on 46 volts is nothing and a lot of gauges wouldn't even show it(analogue gauges). You should be careful though you don't void the warranty by working on it yourself..

Have you tried turning it over on/by the crankshaft with the plug in ? Perhaps it's got too much compression, or perhaps the piston's hitting the sparkplug. Have you tried watching the voltage while it's cranking over ? Perhaps it needs a better/bigger battery.