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chris_drover
06-07-2013, 04:23 PM
My 84 big red is blowin smoke out the exhaust. I just assumed that if I changed the rings that the problem would be solved but according to someone I was talking to there's a lot more to it than that. He told me that I would probably have to do the valves, get the head honed and bore the cylinder and get a new piston along with the rings. As well probably have to get a new timing chain. Is this actually the case or am I correct in assuming that doing just the rings will solve my problem of burning oil? There is a tick coming from the motor as well but was told on here that the 200 motors pretty much came from the factory with a tick.

NeverLift
06-07-2013, 06:52 PM
You need to do a compression test. You should be able to find the factory spec on here somewhere with a little searching.

If your compression is good it's probably just the valve guide seals.
If the compression is low than you might be looking at new piston, rings and a bore job.

6speedthumper
06-07-2013, 08:53 PM
A comp test is only going to tell you that you have compression (good or bad), not that you will have blow-by. Sure, if you have low comp it will be shown on the comp guage, but, that's it. A cylinder leak down test is the best way to get an assement on the condition of the rings.

If you are only experiencing smoking on start up (especially when cold) and it clears up after a few seconds, it is valve seals. If it smokes continuously and never stops, it's rings. Many people get the impression that if you have good comp then it shouldn't smoke, which is not true. Any engine that can start under it's own power (meaning it doesn't need to be pull started or other method to turn the engine over) and run, has adequate comp. (an engine can have enough comp to start and run, but not enough to produce good power. However, that does beyond the scope of my reply). Said engine can have adequate comp but may smoke because the oil control ring(s) are too worn to properly seal against the cylinder wall, and thus oil gets past the oil rings and gets forced past the comp ring(s), where it is burned in the combustion chamber (which makes it smoke continuously because oil gets past the rings on every revolution).

Then there is the opposite side of the spectrum; and engine has comp so low it cannot start on it's own. But, pull start it with another quad, and the engine turns over so fast it "developes" enough comp to start it, and once running it doesn't smoke. Seen that many many times. This is due to the compression ring(s) being too worn to seal effectivly against the cylinder wall, but, the oil control rings are still good and doing their job (keeping oil from blowing past the comp ring(s) and into the combustion chamber, hence the term "blow-by").

Now, on to your problem. If it smokes for a few seconds and clears up, it is your valve seals. To replace them, the head is best to be rebuilt. This intails removing the head, and having a shop do a valve job, install new seals, and replace any other worn componants (to do it right). If you go through that effort, you may as well just do a whole top end, and pull the cylinder off, take the piston out, have it bored and honed if need be, and install a new piston&rings. You've already gone so far to take the head off, another couple fasteners and you can take care of the piston/rings in one swoop. I make it common practice to install a new timing chain, but, you don't "need" to do it. Best to take the tensioner out and see how much further the tensioner has to travel before the chain starts to make noise or jumps timing.

If it is smoking the entire time it is running, it needs rings, and you are better off to have the head rebuilt anyway to be thorough. Hope this helps.

chris_drover
06-07-2013, 08:59 PM
It smokes from the time I start it to the time I shut it off but it pulls like a train. So I need the rings done for sure. I have a spare head, could I rebuild it myself or should I have it done professionally?

6speedthumper
06-07-2013, 09:28 PM
Yup. Needs rings. The valve seals would have to be about gone for them to leak bad enough to smoke like that.

You can do the head yourself, but, you will need a valve spring compressor to do it. However, unless you can re-grind the valve seats and lap the valves, it is best to have a reputable shop do it for you.

You MAY have to have the cylinder bored and honed to fit a larger piston, IF the cylinder is beyond the wear limit. You won't know this until you have the cylinder miched to see how out of round it is. If it is within the wear limit, you can get away with a re-hone, and just install new rings onto the piston (have to do your ring end gap first) and call it a day. If it were me, I'd just replace the piston as well, even if you don't have to bore it. New is better then old, Imo, and there is no sense in trusting a near 30 year part when a new one is probably dirt cheap for that bike.

kb0nly
06-08-2013, 01:17 AM
Just did this on a 84 200ES last month, and doing mine also...

Time to pull the motor out and get to a top end rebuild.. Let me tell you, the 200ES is a PITA to get the motor back in, getting it out is not a problem but reinstalling thanks to the driveshaft u-joint spring is a bugger that will make you swear til a blue cloud hangs over.. I have done it enough times to tell you its just a battle you have to fight until you win.

Unfortunately there is no way to pull the top end without pulling the whole motor out, just how it is on them. And if your going to go through all that trouble don't skimp out on it!!! For a couple hundred bucks depending on the cost of machining i would tear the top end off, buy a top end gasket kit, have the cylinder measured up to see what you need for piston size, get a new piston and rings and have it bored and honed. Get a new timing chain and a tensioner and guide set for it, trust me, the last thing you want to do is have to do this ALL OVER again to save a little money, because the amount of work to pull it a second time and also buying another gasket set will make you want to kick yourself in the butt.

Have the head gone through, get the valves inspected, lap them in if they are ok, new seals, clean out the intake and exhaust ports, etc. I had atc007 on here do the machine work for me on my last rebuild for another guys 84. I have a cylinder and head all rebuilt and waiting for my 200ES that i bought this past winter, its finally time to stop procrastinating and get it done, i will get it done in an afternoon probably this weekend. If you need a step by step for pulling the motor i can tell you from memory how to pull it, i have done mine and a few others, one i did three times because of the owner beating on it, it got more expensive for him every time i had to do it, mainly because i was running out of swear words to use on it.. LOL

If you have good basic mechanical knowledge you can do it, but your going to need a good shop to do the machining and such. I have a valve spring compressor made for these 4 strokes and have done that part myself before, but if you got to have someone do the cylinder machining might as well get the full meal deal and have them do the head to.

If you need the service manual its on my server, link in my signature below.

The 200's do have an inherent tick to the valvetrain, if you ever get one quiet it won't last long. But a stretched timing chain only adds to the noise. So installing a new chain and adjusting the valves correctly will get it pretty quiet, but in my opinion you will never get one totally quiet its just due to the valvetrain design.

chris_drover
06-08-2013, 05:23 AM
Thanks for the informed replies! I have a spare motor in the garage, maybe I'll take my time and and get everything done and ready to install trailprotrailpro I take my bike out of commission. I'll just use her as is and keep the oil to her. Gets expensive using ams oil tho...lol

chris_drover
06-08-2013, 10:46 AM
I have been thinking about the bore. Could I bring it up as big as the 250 big red and just get a piston from an 85 or 86 big red and bolt my rebuilt 200 head back on or would going that big cause more problems or need the components in the head to be changed as well?

6speedthumper
06-08-2013, 12:38 PM
No you can't. Two completely different engine families. You are talking different stroke, bore, cylinder wall thickness, overall design, etc... Idk if the wrist pin would even work in your rod, let alone if the valve reliefs in the piston would match the valve layout of your head. You'd also have deck height issues that would have to be solved with a cylinder spacer, then you'd probably need a custom timing chain made up. The most you can do is get the biggest piston for it (I'm guessing .040" for this ole gal?), and if you can find one, a higher comp piston will add a good "punch" to that little engine. That's about it for performance far as pistons go.

FST does make a big bore stroker kit for the 1st gen 200x. If I'm not mistaken, that share the same BxS and top end as your bike (but I could be wrong, I haven't wreched on both those bikes), but the crank is going to be different because you have a centrifugal clutch AND multiplate clutch. The X only has the MP clutch. They most likely stroke the customer's crank, so you SHOULD be able to send them yours and they can stroke it, then send it back with the matching piston. Again, I do not know the ins and outs of this engine, or the difference between the the two bikes. Either way, this COULD be your only option for more displacement/power gains.

Here is FST's link to the 1st gen 200x page: http://www.fourstroketech.net/#!__products/honda/vstc1=atc-83'-85'-200x . Also, just saw they offer 11.5:1 pistons up to .080" over stock (18cc increase). Just do a little research and see what can be had.

kb0nly
07-16-2013, 07:36 PM
I would stay stock compression ratio unless you like buying high test gas to go along with it...

I run mine on plain old 89 pump gas no issues but i rebuilt it with a stock type piston, just overbored, i have put premium in it, runs kinda rough and hotter believe it or not.

6speedthumper
07-16-2013, 08:46 PM
Most engines tend to need race fuel when the comp ratio hits 12:1. Not all, but, most do. I'm running 11.4:1 on my Warrior with a 39mm FCR (among other mods) on 93octane. For the couple gallons most fuel tanks hold, 93 is not that expensive. I personally don't like to go more then 11.5:1.

shadam
07-20-2013, 05:04 AM
85 200 of mine blows smoke big time ... I joke its a 2stroke ...
she holds her owm with the quads ... just not the long high speed legs of rides

shes got enough power to get thru the deep swamps ... and she makes it ...

forget the $20,000 quad ...

just keep running the old girl with minimal $$$

she apreciated the 94 gas I was running in her,
but don't tell her it was the dregs out of my sled gas cans ...