Mech

lol... I don't argue and I don't fight.

Suppose you looked in the "backfires through carb"..

Blown a fuse.. Get a wiring diagram and start checking the power from the battery onwards using a test light. Check the earth cable too.. A test light is better to use for that purpose than a digital meter which won't detect bad/dirty connections. Check the battery has power and an earth and then start tracing.. I'd jump to the main switch first off after checking the fuses since there's no lights or neutral or anything. If there's power there then onwards, other wise go back towards the battery. And check the main switch is working... Test before(on the power side), and after making sure it does switch on.

Well if you give it a run for a few minutes, pushing it till it just starts to falter, then pull over and turn off without idling, and take the spark-plug out it might look lean, a light colour or white. You could try checking the exhaust isn't blocked. In the manuals they say to take a bung out of the back of the muffler every so often and rev it to clear it of gunk. I've done it though and never got anything out. It's best to test for a blocked exhaust by loosening it at the head and muffler brackets so it can leak real bad at the head. If it runs a bit better like that then it's blocked. but it has to leak real bad. It needs to be ten mills away from the head. Mainly though I'd suspect a lean mixture. The old carb may have needed work, and new aftermarket carbs are almost never set up right for a bike. Aftermarket carbs are tuned in a sort of average way to run on any bike, but not well on any. I'd suggest cleaning and setting to original carb myself.. it's always a better option than buying a new one and then having to do work on it anyway to get it going right.

Try the two sparkplugs 97.. That will show if the spark is failing at revs. There's another thing.. can you describe the bogging.. is it cutting in and out like someone is cutting the ignition about twenty times a second, or just sort of loading up and making noise but not revving. And is it the same revving in neutral or riding it ? Do you think the exhaust could be blocked ? That would cause it to be like that second description there, and perhaps spit into the carb.

These might help.. https://www.partzilla.com/catalog/suzuki/atv/1987/quadrunner-lt300e/headlamp-housing https://www.partzilla.com/catalog/suzuki/atv/1987/quadrunner-lt300e/headlamp And it looks like the headlight out of the standard old lt300. output.pdf

Oh true.. Well if you send us a picture we might recognise it and have some ideas.

Have you got the service manual Jd.. That will explain how to get the headlight off I'm sure. I'd wait till the new switch arrives though in case that's all the problems.

That's a big call Randy, but then so's 11,000 rpm. There's a few things I don't like, like bullying(not saying Randy is), and lying(not saying Randy is), and bad dangerous advice; I oppose them wherever I see them. 97 take a look at #41 and #47. Try those things. That will eliminate stuff real simple and cost you nothing. You can check your valves are sealing properly by pulling on the pull start. It will come up fairly solid if everything's fine. If you can pull it over let us know and we can tell you how to diagnose what's wrong there. You should avoid adjusting the valves because those things are quite prone to self adjusting, and if you follow Randy's advice you will have the same problems he says he has so much experience of. If they are adjusted correctly, they don't give problems for years and years..literally.

If it turns the wheels when it's in neutral, but locks up when in gear, then it is one of the clutches, and if the shift clutch won't turn nice, then it's in the shift clutch almost surely, or, very unlikely, the centrifugal is locked up somehow. Check the centrifugal and crank turns without the shift clutch turning, then take it off and check the shift is what is binding, then take that off again. The problem will be in the assembly of the shift clutch and it's sleeve etc. When you are putting it back together don't torque things up, just tighten them hand tight with a 3/8 ratchet. Those threads are probably getting at risk by now and I'd probably only do them up to 70LbFt in the final assembly if it was me. Tightening with a 3/8 will be tight enough to reveal any binding of that shift clutch, and if there is any binding then take it apart again and redo it. The shift lever thing might be because the circlip isn't on there holding the shift mechanism on the shaft. It's when that shaft moves backwards that you were having trouble with it before and it will almost certainly be the same thing now, it needs to be forwards and it's the circlip that does that. When you have the shift clutch off inspect every part5 very carefully, with a magnifying glass if necessary looking for signs of where they used to fit and rub together, and any signs of where they have been binding now. Check the diameter of the wear marks on the washers and check what they run against that has that diameter. Don't fit a washer against anything that doesn't match the old wear marks. Actually... When you are undoing the shift clutch, just undo the nut one turn and see if that fixes the problem as a first step, that will confirm it is in the clutch assembly order.

He started off with a simple problem, and all we need to do is figure whether it's fuel or spark, then go from there..

What ? Because you have a pump with a bit of corrosion in it, everyone should take theirs apart ? Do you think a dirty pump is the trouble here. Shouldn't we wait till he's pulled the head off and spent a lot of money getting new valves for that before ripping into anything else ? Or do you know that all suzuki pumps are crap and cause a lot of problems, always ? And I suppose there's a particular aftermarket you have fitted that's what everyone should use too. Really Randy.. We're meant to be helping the guy, not sabotaging his whole bike.

Yup that's a fuel pump, and tap.

I'm pretty sure he found nothing.. See we got numbers on the posts now Gw.. It'll be handy for pointing at posts in the thread.. You can #13, #27, #28.. Reference a string of posts at a time. https://www.quadcrazy.com/atvforum/topic/16830-2007-honda-400-rancher-4x4-atv-squealing-sound-when-shifts-into-drivetrx400fa7/#comment-122766

There was a fellah in here a while back had the same symptoms, the squeal, stripped it right down and found nothing, put it back together and it seemed to be right.. Do a search for hondamatic and you mioht find it.. I think it was in this site.. If not it was over the way and I'll have a look tomorrow. I'm pretty sure he found nothing.. Might have just needed an oil change.. haha

The exhaust valve.

You don't need feeler gauges to set the tappets 97, and it's best not to use them. Valves get a pit in the end where the rocker presses and the feelers span the pit and give a wrong reading. You can do it by ear and feel, or by winding the screw in till it touches and then out by the amount that will give the correct clearance.

Koken sockets are the best quality for the money.. I've been overhauling jap bike engines since 1973 Randy, and done dozens of them, as a profession. I've seen plenty of damage.

You should check the hoses for fuel, and you should use two spark-plugs as I suggested earlier to check the spark is strong and consistent.

I have never had any problem with the valves in the ten regular customers bikes or the two I have had.. It's important to get them set right, and then they stay set for years. If you mean the socket won't grip the plug, use a single hex socket, and give it a tap down onto the cap to seat the socket and disturb the O ring under there. If you give them more clearance than they are meant to have, they will hammer into their seats and self tighten. If you set them correctly, the ramps on the cam lowers the valve gently and you will have no problems.

Better to set them correctly 97, and not have to replace them.. I though you wanted to get it going, not wrecked.

"For diagnostic purposes it doesn't matter how big the gap is so long as there is a gap. I used to set it something like 1/8 inch just to get some work done and by the end of the day it was tight again.".. Oh. And you say they have a problem with their valves.. I wonder why you would get that impression.

The clearance is in thousands of an inch, not millimeters. You should barely be able to feel or hear the play, but there should be some. One millimeter is forty thousands of an inch.. to give you some idea of what's required.

I don't think cheap parts are cheap for no reason, and even if they make them out of jap spec aluminium casting material(which is a standard), they can vary greatly and have different characteristics after a run. The spec for casting aluminium are loose enough to give a bit of leeway about it's exact composition, and some of it gets harder after being normally hot, and some gets softer after being normally hot, and some that gets soft after normal use gets harder after an overheat, and some that normally toughens after normal running gets soft after an overheat. It also varies in it's expansion rates. Then there are differences with cycling of heat, some responds well to heat cycling, and some does not.. The jap manufacturers are very particular about what exact composition their casting aluminum is, and we pay for their expertise.

There are diaphragms in the fuel tap and the fuel pump 97, and if they get a small hole in them the fuel gets sucked down the vacuum hoses and straight into the engine. They run rich.