Blodg
12-11-2012, 06:51 PM
OK first off this is not my 400EX but I put it here because I have been reading this forum every day to research for some mods I am doing to the 400EX. Also there isn't really a section for a 350X and not many read the hybrid forum.
When I quit racing 10 years ago my 500RX (bored and stroked 350X) sat for 4 or 5 years. The last 4 or 5 years I have only ridden it a couple times a year. A couple weeks ago I got it out for the first time this year. I am getting back into riding and wanted to check it over in preparation for a trip to the Silver Lake sand dunes next spring/summer. This thing is always a bear to start even when ridden on a regular basis as it has no decompression mechanism. I was worried because it still had gas from last year and I didn't know if it would start at all. Well on the 3rd kick it started for a few seconds and then died. Another 2 or 3 kicks with it running longer each time and it was started! After warm up I took it for a few spins around the yard and it was running great! I was checking it over and noticed the spark plug was bouncing around so I shut it off. I found the plug was loose so I tightened it and it started right back up and I rode for 5 or 10 minutes around the yard again and everything seemed good. I never ride on the road but I decided to do a run down the road to check the jetting. I remember having a 185 in it from years ago but when I pulled the jet it was a 190 and I wanted to see if it was rich or if that was indeed the proper size.
After 5 or 10 minutes on the road I am heading back home (had been running great with no blubber on top) and it dies on me about mid throttle in 3rd gear. After it died the motor was making a "puffing" sound as I coasted to a stop and I guessed I had blown the head gasket. I looked down and the spark plug is hanging from the wire!!! I thought, damn, it must have loosened up again so I waited a few minutes and then started trying to hand tighten the plug while burning the sh*t out of my fingers. After several minutes of a few turns at a time I had it about threaded all the way in and then when I grabbed it to tighten again it pulled all the way out with my fingers! That was when I realized it had not loosened and backed out but it blew out stripping the threads completely!
Has anyone ever heard of this happening? I had the plug tight earlier and the threads were good but like I said the quad has mostly sat for the last 10 years and the motor is also 27 years old so there is metal fatigue. I just got my heli-coil kit in the mail today and may try to fix it this weekend. At first I had planned on pulling the head to tap and install the heli-coil but I have read of guys doing the repair as is on street bikes. They say to coat the tap with grease and it will catch the shavings and several people say they have done this with no problems. Has anyone here ever done that or would you guys do it without removing the head? I am thinking breaking off the tab at the bottom of the coil may be a b*tch and if it were to fall in then the head has to come off. Appreciate any advice.
When I quit racing 10 years ago my 500RX (bored and stroked 350X) sat for 4 or 5 years. The last 4 or 5 years I have only ridden it a couple times a year. A couple weeks ago I got it out for the first time this year. I am getting back into riding and wanted to check it over in preparation for a trip to the Silver Lake sand dunes next spring/summer. This thing is always a bear to start even when ridden on a regular basis as it has no decompression mechanism. I was worried because it still had gas from last year and I didn't know if it would start at all. Well on the 3rd kick it started for a few seconds and then died. Another 2 or 3 kicks with it running longer each time and it was started! After warm up I took it for a few spins around the yard and it was running great! I was checking it over and noticed the spark plug was bouncing around so I shut it off. I found the plug was loose so I tightened it and it started right back up and I rode for 5 or 10 minutes around the yard again and everything seemed good. I never ride on the road but I decided to do a run down the road to check the jetting. I remember having a 185 in it from years ago but when I pulled the jet it was a 190 and I wanted to see if it was rich or if that was indeed the proper size.
After 5 or 10 minutes on the road I am heading back home (had been running great with no blubber on top) and it dies on me about mid throttle in 3rd gear. After it died the motor was making a "puffing" sound as I coasted to a stop and I guessed I had blown the head gasket. I looked down and the spark plug is hanging from the wire!!! I thought, damn, it must have loosened up again so I waited a few minutes and then started trying to hand tighten the plug while burning the sh*t out of my fingers. After several minutes of a few turns at a time I had it about threaded all the way in and then when I grabbed it to tighten again it pulled all the way out with my fingers! That was when I realized it had not loosened and backed out but it blew out stripping the threads completely!
Has anyone ever heard of this happening? I had the plug tight earlier and the threads were good but like I said the quad has mostly sat for the last 10 years and the motor is also 27 years old so there is metal fatigue. I just got my heli-coil kit in the mail today and may try to fix it this weekend. At first I had planned on pulling the head to tap and install the heli-coil but I have read of guys doing the repair as is on street bikes. They say to coat the tap with grease and it will catch the shavings and several people say they have done this with no problems. Has anyone here ever done that or would you guys do it without removing the head? I am thinking breaking off the tab at the bottom of the coil may be a b*tch and if it were to fall in then the head has to come off. Appreciate any advice.