Having a little Trouble.
I recently purchased a 1987 650sx that has been bone stock since it was new. I purchased it from a guy who had it sitting in his garage for 1 1/2 years without being started or anything. I cranked it and after about 10 seconds of cranking it caught and would consistently fire the back cylinder but the front was intermittent.
Now I have..
-removed all of the old gas
-put new gas and a good additive in
-removed the oil injection system and mixed a high quality TCW3 oil in the gas
-put two new NGK B7ES spark plugs in (gapped to spec).
Taking the front spark plug out it will run on the back cylinder like a champ. Both spark plugs are parking in the same manner and color when grounded on the head. I did cut the spark plug wire and re-thread it into the boot to see if that was the culprit. I also cleaned inside both of the boots with electrical contact cleaner and Q-tips.
First I was thinking it was a carb issue, but then why would one cylinder be running good? Could it be the reeds are damaged to that cylinder? Or could it be that something in the CDI box is worn out and not providing a good spark under compression?
Thanks for reading and I look forward to some advice.
Last edited by JC_1992; 06-09-2012 at 04:28 PM.