Hi I appreciate you looking at this. I recently acquired an 85 xl600r. after cleaning the carbs and making all the adjustments oultined in the service manual, the bike sarts and runs good...with the choke on. also seems to run ok in the mid range and high range. I am sure that all the passages are clear and no air leaks clean filter. Without choke it seems to pop and backfire. The carb has PH64AA which is supposed to be on an 84 model year. Also I did notice the slow jet was a 45. I am almost positive this is my problem but would like some reassurence. Also would it be better to buy all new jets for this(PH64AA)carb, or can I buy the jets that are supposed to be in the PH68A-B and they will work fine? Thank you for any input you may have on this subject.
Welcome to 4strokes, The #45 slow jet is way to small it is supposed to be at least a #65 with a #112 or #115 main. Did you reset your valve clearance? .002 on the intake and .005 on the exhaust. Can you take a compression test a let me know what you have? I have the same bike and wondering if they are close.
I could probably due a leak down test, if that would suffice. I did adjust valves to .002 intake and .004" exhaust. Why would someone even have put that 45 slow jet in there? Also still need to know if I can order the jets for the 85 model year carb...I mean i know I can get them but should they work?
Alright ordered my 65 jet from honda marysville, put it in and guess what? No pop or backfire at idle! I am a little curious how a 45 slow jet got in there though. I looked at my primary needle jet and it is a 120. I think when i had them both apart some time ago they were both 120's. I haven't read my plug yet but to those of you who are experienced...with a stock bike will this combo be rich?