I bought a 78 650D a couple weeks ago and I have been working on getting it running. It hasnt run in about 10 years. So far I have replaced the points, cleaned fuel tank and petcock, cleaned the carbs (float, main jets, and float valve pretty well.) I havent adjusted the air screws or anything yet. The ignition is pretty good now. It has spark on all 4 cylinders. I worked in starting it today and i got it to run with full choke for 15-30 seconds, but as soon as I gave it gas it would die. I am thinking that the next steps would be to get timing right on ( I have it pretty close now) , clean up the advance mechanism ( I havent touched it yet, it is probably froze up), and probably rebuild the carbs. I tested the compression and they numbers were decent, but not real good. It is enough to run and if I get it warm, I will test them for real.
Does it sound like I am on the right track?
I also took the airbox off so I could work on the carbs easier. I figure I will have to rejet the carbs eventually, but is their anything else you have to do when switching to pods?
Post edited by: CombatWombat, at: 2005/10/24 10:03
Just bought an '83 KZ650 CSR the first of Sept. It had been in storage for several years. I had the exact same problem at first. It would run at full choke but would die if you gave it gas. I just kept disassembling the carbs and cleaning them and making sure everything was free (nothing sticking) and then putting them back together. Each time it ran better. I did this about 5 or 6 times, with a manual. I never touched the timing, valves or anything else. I had already changed the oil and filter tho. After the last time I put the carbs back on I started riding it to work. I just cleaned it with spray can carb cleaner because I didn't have any of the stuff to soak the carb in. I'll be doing that this winter.
If you follow the steps IN ORDER as outlined in a shop manual for engine tune up, the ignition tune up would have followed valve clearance adjustment and cam chain tensioning. It is a waste of time to adjust carburetors if this stuff wasn't done first. I would also consult a shop manual before adjusting a "needle screw" as I don't have a clue as to what a needle screw is.
When you do get done adjusting valves, cam chain, settting ignition timing, adjusting or replacing points/condensors/plug wires/plug caps, then do your carburetors.
FIRST... synchronize the carburetors at idle. Then set idle mixture for each carburetor and finally idle speed. Let the bike warm sufficiently before trying to take it off choke. There is a VERY good possiblity that the choke pick up tubes are clogged and/or the pilot circuit is clogged in one of more carburetors. Make sure these are free and clean.
wiredgeorge Motorcycle Carburetors
Mico TX www.wgcarbs.com
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