Suzuki king quad 300 idles great but Boggs when you apply throttle

[JustRandy]

I agree not to buy an aftermarket carb.  Get a used one from a suzuki bike (not atv) from ebay.  That's what I did.

I wouldn't fiddle with that cv carb another minute.  Into the trash it should go.

[Mech]

And if the second hand carb is being sold because it has a problem, or isn't set up for your particular four wheeled bike or market ?

More bad advice Randy.. 

Edited July 27, 2023 by Mech

[Gwbarm]

 97 I have not really commented on this very much, you guys are covering it quite well, i watched your video numerous times and it seems around 5000 rpm is when your bogging starts, at this point there is an exceessive amount of gas being blown out of the carb, so is this a lean or a rich condition, im not sure, but either one it should not be blowing gas toward the air box, so 2 thoughts come to mind, is the spark advance working correctly to keep up with the added RPMs which im assuming is controlled by the CDI, im assuming because i have never worked on a king quad, the engine sounds very good for an old engine nice and tight, not to throw another pebble in an already rippled pond, but the only time i have ever seen this happen was on a 2 stroke, the piston was installed backwards, there is an arrow pointing to exhaust on the piston, dont know if yours has ever been rebuilt but just a thought. 

[Mech]

Is that in #126 Gw ? I'll have to download it..

Is it backfiring or just spitting fuel..  They all spit a little, and a blocked exhaust could make that worse..  I'm flying blind here though.. bad internet.

[Mech]

Ok so I downloaded that vid and that blow-back doesn't look bad to me. Once the airbox is connected that fuel will go towards running the engine.

I'd be testing it under load too. Just revving it on the spot like that isn't a very good indication of things.

I'd like to know, does it backfire into the airbox when it's under load and as the throttle's being opened, and how much throttle does it get to before it starts bogging down, and is that on a flat road and which gear etc.. How much throttle, how much load, and whether it is actually firing back into the airbox are all important indicators.

[JustRandy]

2 hours ago, Mech said:

And if the second hand carb is being sold because it has a problem, or isn't set up for your particular four wheeled bike or market ?

More bad advice Randy.. 

Nah most carbs are from bikes parted out.  Check the pics and description.  Do the due diligence required for any ebay item.  Ask questions.

If it's set up for the bike it will be close for the quad and much easier to work on.

The alternative is to keep beating his head on the wall with that cv carb then have a piece of crap carb in the end anyway.

[JustRandy]

2 hours ago, Gwbarm said:

is the spark advance working correctly to keep up with the added RPMs which im assuming is controlled by the CDI

There is no mechanical advance so it would have to be in the CDI.  It's easy to check since he has parts quads and the LT4WD has a higher rev limit anyway.  Or at least mine did.  Maybe different years are different.  Anyway they all should work.

There's a piece of metal tacked onto the flywheel you can see in this pic.  It's tacked in different locations for different models and years to give different timing.  That allows the CDIs to be the same, except the rev limit.

2 hours ago, Gwbarm said:

but the only time i have ever seen this happen was on a 2 stroke, the piston was installed backwards, there is an arrow pointing to exhaust on the piston, dont know if yours has ever been rebuilt but just a thought. 

Interesting.

[JustRandy]

I can hit 11,000 rpm because I have a super light Arias piston that I shaved down and it has a short wrist pin unlike the Wiseco boat anchor pistons.  And I have ovate valve springs that are twice stiffer than the dual springs so I don't get any valve float.  And of course the sport cam.

The original 230 had a 16mm wrist pin and I have pics from a couple guys whose rod punched a hole in the case after breaking.  In 1989 suzuki changed it to 17mm which seems to be plenty strong.  That same piston is carried over to the king, but with a longer rod which helps offset the deflection caused by a longer stroke.  It has potential to be a real beast.

[Gwbarm]

Sorry! Yes Mech it was 126, but you have already figured that out , i have been out working most of the day away from my machine. I thought the gas blowing backward was a little excessive but i have never worked on a 300. Not even sure which carb is on a 300. My Suzuki has a Kei Hin, but its a 400. 

[Mech]

Yeah it's a bit hard to tell for sure but they all do that, and two strokes do it heaps..  with or without the piston backwards.

I had been under the impression he was saying it backfired into the carb, which it well could do under load..

[Mech]

Oh yeah, the 300 has a mikuni and the 400 the keihin.. 

[Gwbarm]

I figured it was probably Mikuni, the 400 i have does have the Kei Hin, but interesting i have not found a suzuki name anywhere on that engine, and it was also on the Arctic Cat of that era. So not sure if it is actually a Suzuki engine. Usually they have the name stamped on it somewhere. 

[Mech]

Oh yeah, I thought suzuki made engines and other companies used them, but not the other way around.. Interesting.

[JustRandy]

19 minutes ago, Gwbarm said:

I figured it was probably Mikuni, the 400 i have does have the Kei Hin, but interesting i have not found a suzuki name anywhere on that engine, and it was also on the Arctic Cat of that era. So not sure if it is actually a Suzuki engine. Usually they have the name stamped on it somewhere. 

It's a suzuki engine that arctic cat used.  The king engine is the same as the 1985 230 quadsport with some refinements.

[Gwbarm]

Good to know that, thanks for the info Randy

[JustRandy]

1 hour ago, Gwbarm said:

Good to know that, thanks for the info Randy

No problem Gw.  The biggest difference between them is the cat had dual rear a-arms and a gravity fed tank, but higher center of gravity.  I'm not sure but I think the cat had real cv joints too instead of u-joints in a boot.

Someone on youtube made a King Cat which is a King with the Cat's a-arms, but I couldn't find the video.

Here's this though:

 

[Gwbarm]

Thanks Randy , i really enjoyed watching the video, it has all the bells and whistles and the controls are so convienient, and mechanical A+, with diff lock and super low gear is handy. Dont see those in my area very much and when you do they are really abused and trashed, even worse than the Eiger i got. 

[97kingquad]

19 hours ago, Mech said:

Is that in #126 Gw ? I'll have to download it..

Is it backfiring or just spitting fuel..  They all spit a little, and a blocked exhaust could make that worse..  I'm flying blind here though.. bad internet.

It Boggs a bit as well

16 hours ago, Mech said:

Yeah it's a bit hard to tell for sure but they all do that, and two strokes do it heaps..  with or without the piston backwards.

I had been under the impression he was saying it backfired into the carb, which it well could do under load..

I'll take a better video tonight 

[Gwbarm]

I thought your video was good, except couldnt see what the exhaust looked like, i heard the bog a little bit, but didnt see any backfire, i thought it ran fairly well for an old engine, i thought the blow back seemed excessive but Mech thought it was normal and im not that expierenced on your age King Quad. How does it do when you driving it ,is it worse, or does it die. or is that when it backfires, also if you take it up slowly to the revs is it better worse or the same.

[JustRandy]

1 hour ago, Gwbarm said:

Thanks Randy , i really enjoyed watching the video, it has all the bells and whistles and the controls are so convienient, and mechanical A+, with diff lock and super low gear is handy. Dont see those in my area very much and when you do they are really abused and trashed, even worse than the Eiger i got. 

They are worth restoring should you take a notion to.  I always say it's the most fun you'll ever have at 1 mph lol

Super low 1st and 2nd are lower than 1st gear low.  I think 3rd gear SL is the same as 1st gear low.

It will pull my truck with the hubs locked in 4x4 and truck manual transmission in 2nd.  It turns the truck engine over.  It won't pull it in 1st gear though.  It just digs 4 holes.

Super low is really nice.  It's fun putting through the woods off the trail, crawling over logs real slow and not worrying about jostling stuff off the racks.  It's handy for backing a loaded trailer real slow.

And I can shift ranges on the fly.  So from 2nd SL I just shift into low and it feels pretty natural.  From there I can either shift into 3rd or shift into high if I don't want to use my foot.

The only thing I wish it had is reverse from any gear like the yamaha warrior.  Too often I'm in 3rd or 4th SL and it's a long way to find neutral to engage reverse.

But I wouldn't trade it for anything.  If someone came over with a Can-am 1000 wanting to trade I'd send them away.  I could always save up to buy a can-am but I don't want to go through all the work again to build another king.

[Mech]

I'd put the inlet hose back on and ride the bike to test it 97.. If it backfires then it will be as I say, if it doesn't then you should check the valve clearance and even possibly the valve timing, but a lot of single cylinder engines puff out backwards like that and I wouldn't consider that a major symptom on it's own.

 

[Mech]

Your slide needle should be sprung loaded downwards. There's meant to be a small spring pushing it down, and the spring is held down by a plastic bit with an O ring on it. The O ring is all that holds the plastic bit from pushing up. If the O ring isn't on the plastic bit, or if it's old and hard, or if the plastic bit can be pushed up and out of place by you pushing the needle up slightly against the spring, but without actually pushing the plastic directly with the needle, they you should change the O ring.  The needles always wobble around sideways in the slide, that's ok.

[JustRandy]

Sometimes needles wear from vibrations.  You can see worn spots on this one.  The needle jet would also be worn.

[97kingquad]

5 hours ago, Gwbarm said:

I thought your video was good, except couldnt see what the exhaust looked like, i heard the bog a little bit, but didnt see any backfire, i thought it ran fairly well for an old engine, i thought the blow back seemed excessive but Mech thought it was normal and im not that expierenced on your age King Quad. How does it do when you driving it ,is it worse, or does it die. or is that when it backfires, also if you take it up slowly to the revs is it better worse or the same.

It really isn't drivable, it will bog at different times as it warms up 

3 hours ago, Mech said:

Your slide needle should be sprung loaded downwards. There's meant to be a small spring pushing it down, and the spring is held down by a plastic bit with an O ring on it. The O ring is all that holds the plastic bit from pushing up. If the O ring isn't on the plastic bit, or if it's old and hard, or if the plastic bit can be pushed up and out of place by you pushing the needle up slightly against the spring, but without actually pushing the plastic directly with the needle, they you should change the O ring.  The needles always wobble around sideways in the slide, that's ok.

What would happen without the o ring 

[Mech]

So it won't even move ?  Not even if you just give it minimum throttle ?

Is it that bad with the carb to airbox hose on as well ?  The CV carbs are fussy about their air-cleaners.

If it idles nicely, then it should run up to about 1/4 throttle, and you should be able to get it moving like that.

[97kingquad]

6 minutes ago, Mech said:

So it won't even move ?  Not even if you just give it minimum throttle ?

Is it that bad with the carb to airbox hose on as well ?  The CV carbs are fussy about their air-cleaners.

If it idles nicely, then it should run up to about 1/4 throttle, and you should be able to get it moving like that.

It will move but I cant go more than quarter throttle and if I'm slow on an incline it Boggs and won't go up. Then I can let it sit for a minute and put it back in gear and take off a bit then it Boggs again 

[Mech]

Without the O ring the needle jumps up and down and fuel gets chucked in there in a completely random fashion, and generally far too much of it.. And that doesn't look like any part I've ever seen in there for the job. It normally is about 20 mm long, has an O ring on the bottom then a flange and a flatter part that's serrated so it can be grabbed with a pair of pliers..

Find a bit of rubber hose about 6mm diameter and use that to jamb down on top or that spring temporarily and see if that fixes it. If it's held down by the spring it will move up, but against the spring pressure, not completely freely.

[97kingquad]

19 minutes ago, Mech said:

So it won't even move ?  Not even if you just give it minimum throttle ?

Is it that bad with the carb to airbox hose on as well ?  The CV carbs are fussy about their air-cleaners.

If it idles nicely, then it should run up to about 1/4 throttle, and you should be able to get it moving like that.

Yes I can move it like that but like I said before it Boggs on an incline 

[Mech]

Well I must have missed that bit about the incline..

There are two versions of carb, one with a steel cover and one plastic.. one has a diaphragm spring about 10mm diameter and the other diaphragm spring is about 14mm diameter.

I'm thinking yours is the plastic cap and the 14mm spring, and on that one there is a tower that comes up around the needle that has four slots in it.. Is that right ?

[97kingquad]

2 minutes ago, Mech said:

Well I must have missed that bit about the incline..

There are two versions of carb, one with a steel cover and one plastic.. one has a diaphragm spring about 10mm diameter and the other diaphragm spring is about 14mm diameter.

I'm thinking yours is the plastic cap and the 14mm spring, and on that one there is a tower that comes up around the needle that has four slots in it.. Is that right ?

Yes but when you say cap do you mean the cover concealing the needle because it is metal an I'm not sure what piece you mean for the spring, mine doesn't have anything but that flat plastic part