Hey guys I'm new here and got serious problems,I have a 1993 ex 300 with a new battery,cables,solenoid,starter,the quad will not turn over unless I have the sparkplug out,its driving me crazy,I jumped the starter direct off a car battery and still won't turn over,the quad was running fine before this,I need help please someone point me in the right direction

 

So what happened to start this off? was it running fine, then suddenly started turning over hard, then you replaced these parts, or did it start after you installed these parts? Does it spin over fast with the plug out, or just barely? with the plug in, does it try to crank and stall out the starter? What happens if you put your finger over the hole and try to start it?
Need more information !!

 

I changed everything because of this,yes it flies over when the plug is out and when I put my finger over it it won't turn over,it seems like a compression issue or timing,does anything retard the timing on these quads so they will turn over,and there's also no compression release like my old Honda trike I used to have,I'm completely lost here

 

And yes this is y I tried all the new parts because it started acting up

 

That is very odd you can stall it with your finger over the plug hole, there should be about 130 psi coming out of that hole, should blow your finger off the hole on compression stroke. To verify its not a timing issue, get the flywheel on TDC ( line up marks in inspection hole) and check you cam gear timing mark, could be you sheared a flywheel key and now it jumped time. But a healthy starter with a new battery should still be able to crank it over, even against the compression stroke, no matter what the timing, it just wouldnt run..... still having a problem with you being able to hold your finger on it and stall it out, trying to get a compression reading is going to be tough.

 

when the plug is out it does blow my finger off the whole if i crank it over and while cranking i try to do it so yes i believe the compression is fine,every once in a while it started not wanting to start and it seemed like the ground was bad but i changed everything,IT seems like it needs a compression release,im stuck and dont know what to do im so fustrated,is there anything that controls the engine while it cranks,i do mechanic work for a living an two other mechanics also looked at it but cant figure it out either

 

I would start with verifying it didnt jump time, see if the TDC mark and the cam gear timing mark are lined up, check valve lash while you got it there, and go from there.

 

Do a compression test. If it it really high, it could be carbon build up on the top of the piston. Easy to fix. Pull the head off and clean the top of the piston.

 

How am I suppose to do a compression test when I can't get the motor to turn over lol