200X Top End Help....(Updated Please Help ME)

[MPNX2]

I just rebulit the topend of my 83 200X. I havent gotten it ruuning yet but I have ran into a problem. I have the motor all assembled and back in the frame. The carb and the exhaust pipe are not installed yet so as you can see it is far from running. My problem is this. I decieded to gap a new spark plug and put it in that went well. Then deceided to check for some compression with the kick starter. I started moving the kickstarter slowly and then it froze. So I pull out the plug and I could see the piston through the hole. I then took off the inspection covers on the oppiste side of the engine where the timing marks are the crankshaft bolt. I rotated the motor clockwise and the piston fell. I kept rotating the motor and it seemed like the piston traveled up and then back down and on the second time back up it froze again. I am assuming that there is a vavle hitting the piston before it gets to TDC. I did install a new Webcam, new piston, new valve springs, the cylinder was bored 1mm over and the piston is 10.25 to 1 compression. My service manual is missing the pages on how to install the cam so I kind of did it by memory. Can anyone help me??

[BigRedRunner]

Set the timing mark on the stator to "T". Remove the sprocket from cam and be sure your lobes are pointing down. You do this so when you place your top cover on, the valves won't be open and make for a difficult time. Then all you do is see if the dot on your cam sprocket lines up with notch in your top cover. If not, then take apart and move the sprocket to another link and try again. Be sure your sprocket bolts are tight. I had mine about done and forgot to do that :oops: . Fortunately for me though, I was gently moving it over by hand. If something doesn't move freely, don't ever force it.

[jeswinehart]

hi MPNX2.
the info BigRedRunner said is correct .
if you'd like to read those pages ( 3 ) from my manual , i scanned them off and i'll pm you my e-mail address so you can send me yours. title it cam info please.
the info is the same for the 185 also ( you won't use the decompression lever info ).

i'm gonna be off line for a couple of hours,,, got stuff to do but will check back before i crash for the night.

john

[samster143]

From what I am hearing you should check to see if anything has fallen into either your exhaust or intake port. If a small item has gotten in there (small nut or bolt) it will lodge between the valve and the valve seat stopping engine rotation. If this has happened you will need a new valve and possibly need the valve seat to be reconditioned. This may or may not be your problem, but this can easily happen if you don't keep tape on those ports when nothing is bolted to them.

[BigRedRunner]

Did you put new valves and guides in? My genuine Honda ones actually had to be honed out in order to fit. That might cause things to catch. Crazy, huh? That deal I was talking with having the sprockets bolts tight will keep it from moving. I started to put my CDI together and one of my bolts wasn't in very far on the sprocket and was catching things up. I had it on and off so many times setting the cam timing, that it slipped my mind. Glad I was alert when I did the jug and everything else though.

[MPNX2]

I plan on pulling the rocker arm cover off here today and looking. I had a machine shop put in new valve springs and retainers and recondition the seats. I am using the same valves they said that they were fine. I will keep you all updated. Thanks for all the help.

[MPNX2]

ok I think that I have the cam right now. After I put the cylinder head cover back on it turns over well. Then when I put the generator base plate on and attempt to turn the crankshaft to align the marks it seems hard to turn over again. What could be causing this....I cant imagine that this could be so difficult.

[MPNX2]

The motor does turn over it is just not as easy as when the generator base plate is not on. After the base plate is installed it is harder to turn over... IS this normal??

[MPNX2]

I am going to take it into a machine shop today and let them look at it...I hope all is well with it..

[ATCMedic]

sounds like you don't have the right bolts holding the cam sprocket on and it's hitting the pulse generator housing. If the length is just a couple of threads too long it will space the cam out too far and it will cause interferance, same goes for the bolts having too thick a head on them. check to see if both bolts match, if they don't (one appears stock and the other is a hardware store replacement..)find a replacement to match the shortest/thinnest head bolt you have and it should fix your problem.