KDX noob

[edgeman68]

Dear sirs. I just acquired a 1990 KDX200E last night. It had been sitting for some time and the kid who had it was unable to get it started. I knew it had to be clogged jets as it would fire with starting fluid. I brought it home, took the carb apart and cleaned the jets, reassembled and it fire 3rd kick. Seemed to run great. Upon closer inspection however there appears to be something missing off of the right side of the engine cylinder. I know absolutely less than nothing about 2 strokes, but I know enough to know something doesn't seem right here. There are 3 bolt holes for some kind of cover that is missing. The cover would be over some sort of roller wheel assembly. Just behind it sits a shaft of some kind with a hole for a pin near the top of it. I have pics I could show, but it appears I cannot post a pic in this forum. If you message me I will gladly email or text a pic either one to help someone identify it. Can someone please tell me A) what is missing, and B) will it harm the motor if I run without it. I bought the bike to teach my stepson to ride and he is dying to take it out this weekend. Is it safe to ride in its present state with this whatever it is missing?

[Tenmag]

I think the part your missing is listed as the governer cover, I wouldn't ride with it missing just because it would let so much dirt and contamination into the innards of the engine. Looking on rocky Mountain atv website they list it as part number 14024-1786 and it's about $10 the gasket is part number 11009-1934 and about $4 the bolts are M5x25 which you can probably find locally or they're like a quarter each on that same site.

[edgeman68]

The lever arm is broken off the top of that shaft. Without this governor being actuated it won't hurt the motor?

[Julien D]

You need a rebuild of the KIPS valves, most likely. It's a weak spot on the E bikes. There are steel replacements available from a member here. It will not hurt the engine, however performance will be way down without the valves working. Do a search here on KIPS and you will find loads of pics and info.

[KDXGarage]

You can post pics from photobucket or other sites.

[bufftester]

Yes, sounds like someone tried to take the KIPS shaft off not knowing its left hand threaded and broke it. You have no exhaust valve as it sits. Not hard to fix. Definitely would advise against riding it until it's sorted out, which will give you time to sort through the rest of the bike. In my experience, if you find something that glaring, there's probably a half dozen other gems not as easily visible.

[edgeman68]

No exhaust valve? That doesn't make any sense as it seems to run pretty good, idles well, power doesn't seem too bad. Granted I have only run it up and down the street a few times, but it seems solid enough I could teach him to ride on.

[bufftester]

Clarifying, you have an exhaust valve (3 actually) but they are not working. Sure the bike will run, just not as well as it could. The valve only comes into play above ~6000 rpm, below that you won't see a difference. With that KIPS cover missing dirt has an ingress point into the head (never good), and if the pawl at the top of the shaft is broken, I would really check the bottom of the shaft to make sure the pin is still attached and not rattling around the cases.

This is what it should look like:


I assume this is what it does look like (minus the lever and nut at the top):


So to actually answer your questions:
A. parts 130, 14024C, 11009, and maybe 92143 and 482 from this Parts Diagram, and 49006, 92015, 13168, and psossibly 49114A (if the shaft is broken at the top where the left hand threads are) from this Parts DIagram

B. Probably not, assuming the rest of the KIPS shaft is intact. It's also probably safe to ride, though I would advise fixing it first.

[edgeman68]

You nailed it bufftester. The top of the shaft is broken off where the threads should be. If it's safe to ride at low speed I guess I will give him a lesson or 2 on it while I wait for parts to come in. Sounds like a have a crap load of work to do on my little $400 find. Knew it was too good to be true.

[bufftester]

Lol, they always are. Though for an initial $400, you won't have to put much more into it and they are basically bulletproof.

[david]

No exhaust valve? That doesn't make any sense as it seems to run pretty good, idles well, power doesn't seem too bad. Granted I have only run it up and down the street a few times, but it seems solid enough I could teach him to ride on.

They aren't exhaust valves of the same function as a 4 stroke engine. These are called Power Valves and they alter the size and shape of the exhaust port, which moves the power band to a different rpm range.