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Just bought, low cokpression, questions

Posted: 11:56 pm Feb 10 2016
by El Gran Jamon
Hi and thanks, new here
Just bought on Sunday a 1990 kdx200 e2 model. Has compression at 90 psi. Doesn't feel very powerful at all, this coming from a guy who rides an xr280 in the forest and occasional slow rocky desert.

Questions:
1. How much labor is involved in a top end? How many hrs, not counting having to send a cylinder out for plating, parts chasing, etc but including pulling the kips apart and replacing, cleaning, etc? I've done top ends on xr's, not too inept but haven't had a kips apart. Day job? How many hours if I was to contract it out to a reasonably skilled shop?
2. I figure if. I'm going to be in there,might as well do it right and do it once. Otherwise I'm not giving this two stroke thing a fair shake :grin:
I understand there are some cylinder or head mods and a special valve, reed kips or steel kips replacement doohickies that bring it up towards 36 hp? Also something called a "torque ring" which is essentially a fat washer between the head and the header pipe?

What I'm trying to get out ot the bike is a lighter, faster xr, low end torque as much as possible. Bike has an fmf woods header on it and a Powe core muffler, I understand I need the turbinator muffler with the spark arrestor for public lands, and probably should have all this in place b4 jetting so I don't waste my time. Can this bike be run Ata crawl on rocks and opened up for some 45-55 dashes or in some cases long desert roads without hurting it or am I asking too much of a two stroke? I'm getting mixed info from two stroke buddies.
3. Last wuestion, looks like the shock is leaking a bit of oil. Dunno how long it's. Een doing so, but seems a bit harsh on square bumps like curbs at 20 mph. Forks are kx and do ok. I weigh 190, seller was a 120 lbs woman. Has a blue spring on it, which I hear is stock. It's possible the shock is too low in its stroke, but I like the lower height.

Hoping to use this bike as a cross trainer on rocks, wheelie easier than a xr, so far not seeing it! It is CA plated, biggest draw.
Thanks,

Chuck

Re: Just bought, low cokpression, questions

Posted: 11:03 am Feb 11 2016
by Jaguar
be more adventurous in regards to the engine tear down. finding out exactly how long it takes robs part of the adventure of doing it.
JUST DO IT
replace the rings, head gasket, base gasket, KIPS valves, spark plug and it will go anywhere, do anything (except serious motocross)

Re: Just bought, low cokpression, questions

Posted: 02:19 pm Feb 11 2016
by Julien D
Top end on the KDX will be dreamy easy compared to your XR. Grab a manual (the cyclepedia version online is great!), and go at it. I expect you can get it done in a few hours. If the cylinder needs a re-plate, you'll have to send it off for that. Otherwise it's an easy do-it-yourself job.

Just bought, low cokpression, questions

Posted: 03:59 pm Feb 11 2016
by El Gran Jamon
Ok,
Thanks, I did download it, will give it a shot. Have a local guy thought I might try to save time,but... nobody takes care of your stuff like you, eh? I need to repair a couple small items, may run it this weekend briefly. Shock will have to be a first priority, as the internals will get damaged with no oil, kinda a catch 22 because I'd only like to open it once and safe money, but can't tell what it needs until I ride it :grin:

If I run into trouble or kips questions will post up.

I see a carb mod and a head milling job people are very pleased with. Should I just go ahead and do that since it will be apart?

Re: Just bought, low cokpression, questions

Posted: 04:25 pm Feb 11 2016
by Julien D
The head mod offers some small improvement for the 200, more so for the 220. The carb mod is excellent.

Re: Just bought, low cokpression, questions

Posted: 05:12 pm Feb 11 2016
by El Gran Jamon
Thanks,
What if after market reeds, or
Kawasaki KDX200 steel KIPS valves and idler gear with bushes? This looks like a 150 dollar deal in real money (British )

Also appears a kayaba shock, is there a recommended gold valve or shim stack mod for a 190 lbs guy? I want it safe for square edged bumps like a curb at 30 mph or more then firm up.

Last question, once this is done, can I run this bike like an xr400? Miles at a constant speed, say 45, 50 mph if on a long desert road? Neighbor was scaring me on that! Saying this is anon off ype bike for cooling, no chance at longevity unless run slow on slow trails wire changing speed..

Re: Just bought, low cokpression, questions

Posted: 06:40 pm Feb 11 2016
by Jaguar
obviously your friend has never owned a KDX

Just bought, low cokpression, questions

Posted: 12:06 pm Feb 12 2016
by sarrant
El Gran Jamon wrote:Hi and thanks, new here
1. How much labor is involved in a top end? How many hrs, not counting having to send a cylinder out for plating, parts chasing, etc but including pulling the kips apart and replacing, cleaning, etc? I've done top ends on xr's, not too inept but haven't had a kips apart. Day job? How many hours if I was to contract it out to a reasonably skilled shop?
Not counting pulling the bodywork, intake/exhaust, and assorted prep, I think your average somewhat-experienced garage mechanic can do a two-stroke top end for most bikes in less than an hour. Some bikes (say a PW50), less than 10 minutes. It's exceedingly simple compared to a 4-stroke.
Can this bike be run Ata crawl on rocks and opened up for some 45-55 dashes or in some cases long desert roads without hurting it or am I asking too much of a two stroke? I'm getting mixed info from two stroke buddies.
This sounds like ideal use for a KDX
3. Last wuestion, looks like the shock is leaking a bit of oil. Dunno how long it's. Een doing so, but seems a bit harsh on square bumps like curbs at 20 mph. Forks are kx and do ok. I weigh 190, seller was a 120 lbs woman. Has a blue spring on it, which I hear is stock. It's possible the shock is too low in its stroke, but I like the lower height.
First and foremost you need to rebuild the shock if it is leaking oil. Once it is damping properly, then you can make a judgement on it's harshness.
Last question, once this is done, can I run this bike like an xr400? Miles at a constant speed, say 45, 50 mph if on a long desert road? Neighbor was scaring me on that! Saying this is anon off ype bike for cooling, no chance at longevity unless run slow on slow trails wire changing speed..
No problem whatsoever. This bike is sold in many markets as a street/dual sport.

Re: Just bought, low cokpression, questions

Posted: 10:27 pm Feb 12 2016
by El Gran Jamon
Ok, got a good 40 miles on it out at randsburg. Seems to be coming back to life. More I use it better it runs, probably sat a bit, carb gummed, does the kips system gum up then start working? Seems limited in high rpm like the secondary chamber (I believe that's what the power valve does) I did replace the air filter, which was flaking apart. Suspension seems better than my xr250r, this bike has a lot if fun potential, and Damn light! Screaming in first at the top of some hills tho, needs a few more beans.

Thabks for the tips. Will pull it down, do a top end, figure out the kips and send out the carb. Very flick able bike.

Re: Just bought, low cokpression, questions

Posted: 02:05 pm Feb 13 2016
by TheRadBaron
You might already know this but there's a very good chance that the KIPS valves aren't working. I'd budget some money and shipping time for the BDK steel valves. If your bike doesn't need them now, it will someday (probably soon).
Anyway, welcome and enjoy your KDX. I think it will be very much to your liking. I've done a lot of mods to my '89 and it really rips. Totally different class than an XR. I'm not knocking XRs, though. I'm fond of 4-stroke Hondas, but my KDX would eat one for lunch on the trails.

Re: Just bought, low cokpression, questions

Posted: 02:53 pm Feb 13 2016
by Chilly
I just sent my cylinder off for plating and found 2 broken pieces in the kips. Total cost 434.00 to fix it right. Got to pay to play is how I look at it.

Re: Just bought, low cokpression, questions

Posted: 04:17 pm Feb 13 2016
by Tedh98
Chilly wrote:I just sent my cylinder off for plating and found 2 broken pieces in the kips. Total cost 434.00 to fix it right. Got to pay to play is how I look at it.
What pieces broke? You have an H-series correct?

Re: Just bought, low cokpression, questions

Posted: 05:07 pm Feb 13 2016
by Chilly
The small gear to the left of the kips cover. They call it a gear, LH valve rod. And the rod on the left hand side that slides up inside the cylinder.

Re: Just bought, low cokpression, questions

Posted: 06:39 pm Feb 13 2016
by Tedh98
Wow, that must have been some good damage to total a couple hundred bucks. Glad you were able to get it fixed up.

Re: Just bought, low cokpression, questions

Posted: 10:04 pm Feb 13 2016
by TheRadBaron
In the first post he says it's a '90, so E-model (with associated KIPS problems).
And $434 isn't too bad of a deal at all if that includes the plating job, piston kit, and KIPS parts. I did the same thing to my '89 when I got it. I spent a bunch of money on a replate, piston kit, KIPS parts, RB mods, etc., etc. Lots of money up front but now I have a bike that I know is fresh and everything operates properly. And, oh, does it run so good. :cool:

Re: Just bought, low cokpression, questions

Posted: 10:16 pm Feb 13 2016
by Tedh98
TheRadBaron wrote:In the first post he says it's a '90, so E-model (with associated KIPS problems)
Right, but I was asking about the other members situation not the OPs. Just surprised that an H series would have that much damage from broken KIPS parts.

Even E-series dont suffer much other damage than just the broken valves.

Re: Just bought, low cokpression, questions

Posted: 09:07 am Feb 14 2016
by Chilly
Yes the 434 included the kips parts replating. I had the dealer take the kips out and put it back together. So 60 dollars in labor. The kips parts was 130. I bought the bike for 600 and I figured I would go through it while its winter. I have put a new seat cover, clutch lever, front wheel bearing and front tire, and rebuilt the whole top end. I think I'm close to 1600 now bike and all. Not bad considering I will have a new motor and a old frame pretty much. I'm just glad I didn't pay 1200 for it then have to do all that work to It.

Re: Just bought, low cokpression, questions

Posted: 09:32 am Feb 14 2016
by Tedh98
Chilly wrote:Yes the 434 included the kips parts replating. I had the dealer take the kips out and put it back together. So 60 dollars in labor. The kips parts was 130.
$240 for the plating isn't too bad. I assume some welding work was needed for the repair.

Just bought, low cokpression, questions

Posted: 10:08 am Feb 14 2016
by El Gran Jamon
Yeah, quite possible my kips valves r stuck, and possibly damaged. My smart 2 stroke buddy rode it yesterday and said power valve is stuck. He's a yz guy, but got a little tear in his eye when he saw the plate. Little older than me and said these are some great bikes from back in the day, he's always been a Yamaha man, but lost to a few of these years ago.

Anyhow, queston, the steel kips maker in Britain, does that kit have all the needed parts? Will the steep shafts, valves not damage anything?,I assume Kawasaki made the originals of alloy for a reason, to preserve a drive gear further down from damage in the event of a jam or something seizes, strip the alloy not the deep in engine gear. The kit is a lot of cash as well.

Anyone with experience? New product..

Re: Just bought, low cokpression, questions

Posted: 10:10 am Feb 14 2016
by Chilly
Yeah and includes shipping both ways. I'm going to clean everything tomorrow like we talked about and then put it all back together.