77500Xs Posted September 8, 2008 Share Posted September 8, 2008 Hey guys! I am a new member with a recent purchase of a 1977 Yamaha 500 xs with 15000 original miles and unfortunately have my first issue with the ignition. After a nice weekend of riding I washed and waxed her up only to find that it now will not start. I have juice up to the ignition switch as the neutral indicator lights up but the start button doesn't work assuming some relay or other switch has failed in between. I cannot kick-start or compression start the bike either. I checked and rechecked all fuses and connections; battery level is fine. I started testing the smaller ignition components with a tester light not really knowing where to start nor their functions. I don't know if the water from the wash fried something or not. I have the technical manual but unfortunately doesn't provide diagnosis with starting issues. If anybody has any ideas on where to start it would be greatly appreciated, thanks. P.S. The bike has the upgraded ignition box for the points but no power is leading into it. Link to comment Share on other sites More sharing options...
JimR Posted September 8, 2008 Share Posted September 8, 2008 Hey guys! I am a new member with a recent purchase of a 1977 Yamaha 500 xs with 15000 original miles and unfortunately have my first issue with the ignition. After a nice weekend of riding I washed and waxed her up only to find that it now will not start. I have juice up to the ignition switch as the neutral indicator lights up but the start button doesn't work assuming some relay or other switched has failed in between. I cannot kick-start or compression start the bike either. I checked and rechecked all fuses and connections; battery level is fine. I started testing the smaller ignition components with a tester light not really knowing where to start nor their functions. I don't know if the water from the wash fried something or not. I have the technical manual but unfortunately doesn't provide diagnosis with starting issues. If anybody has any ideas on where to start it would be greatly appreciated, thanks. P.S. The bike has the upgraded ignition box for the points but no power is leading into it. Hi there, I know it sounds well silly but is the kill switch in the run position ? that would stop the 'electric shoe' from working and also kick starting and bump starting would fail also. Perhaps you knocked it off when cleaning ? Link to comment Share on other sites More sharing options...
77500Xs Posted September 8, 2008 Author Share Posted September 8, 2008 Hi there, I know it sounds well silly but is the kill switch in the run position ? that would stop the 'electric shoe' from working and also kick starting and bump starting would fail also. Perhaps you knocked it off when cleaning ? Haha...Yes it is. It does seem as though it is something as simple as a switch. I was questioning if power was getting up to the switches on the right handlebar but my headlights do work along with the control switch. Not sure how to start eliminating some of these factors as far as their sequence in the ignition cycle. Thanks for the response Jim. Link to comment Share on other sites More sharing options...
JimR Posted September 8, 2008 Share Posted September 8, 2008 Haha...Yes it is. It does seem as though it is something as simple as a switch. I was questioning if power was getting up to the switches on the right handlebar but my headlights do work along with the control switch. Not sure how to start eliminating some of these factors as far as their sequence in the ignition cycle. Thanks for the response Jim. Hi There is the kill switch in its central position ( not to right or left) If so do the following Check that you have a spark from the HT leads If not remove the points cover (small one on the r/h side of the motor), you may have filled it with water. but from a going concern to a starter motor not turning the engine over by a press of the button smacks of kill switch. You could also short the starter soleniod out to see if the starter motor turns the motor over. But on repeated attempts to start the motor with no spark it will be full of fuel. regards Jim Link to comment Share on other sites More sharing options...
77500Xs Posted September 8, 2008 Author Share Posted September 8, 2008 I am aware of the kill switch as it is in it's correct position. I have power going into the starter solenoid but do not have any power coming out; could this be a switch not allowing power out of the solenoid down to the starter or the solenoid itself? Something is faulting the loop before powering the starter and I'm only assuming the kill switch has this control. I also had a continuous problem in relation to this too: while driving for a while and come to a stop, if I tilt/turn the fork and handlebars to the left the engine would cut out. I could get the bike running again by kick-start only; the electric start would crank and crank but for some reason would not allow the engine to fire until the bike cooled down... I have no clue.. Link to comment Share on other sites More sharing options...
JimR Posted September 8, 2008 Share Posted September 8, 2008 I am aware of the kill switch as it is in it's correct position. I have power going into the starter solenoid but do not have any power coming out; could this be a switch not allowing power out of the solenoid down to the starter or the solenoid itself? Something is faulting the loop before powering the starter and I'm only assuming the kill switch has this control. I also had a continuous problem in relation to this too: while driving for a while and come to a stop, if I tilt/turn the fork and handlebars to the left the engine would cut out. I could get the bike running again by kick-start only; the electric start would crank and crank but for some reason would not allow the engine to fire until the bike cooled down... I have no clue.. Ok you did not say that the machine cut out when the h/bars are turned left ! that indicates a wiring loom problem. you are trying to over complex nwhich I guess if you want help you should return all symptoms rather than what you wish to release. Regards Jim Link to comment Share on other sites More sharing options...
77500Xs Posted September 8, 2008 Author Share Posted September 8, 2008 Ok you did not say that the machine cut out when the h/bars are turned left ! that indicates a wiring loom problem. you are trying to over complex nwhich I guess if you want help you should return all symptoms rather than what you wish to release. Regards Jim Thanks Jim, I'll have to recheck my connections in the headlight assembly to my h/bar switches. Hopefully its as simple as a connection in the loom. Link to comment Share on other sites More sharing options...
JimR Posted September 8, 2008 Share Posted September 8, 2008 Thanks Jim, I'll have to recheck my connections in the headlight assembly to my h/bar switches. Hopefully its as simple as a connection in the loom. I guess not the turn left thing produces a break in the wiring under the bottom yoke not in the headlight assy. check the wires from the section h/l bowl to frame. I guess the outer plastic is broken and some wires are broken .. black with white trace stands a chance Regards Jim Link to comment Share on other sites More sharing options...
77500Xs Posted September 8, 2008 Author Share Posted September 8, 2008 Thanks again Jim, I'll check that out. Link to comment Share on other sites More sharing options...
Ttaskmaster Posted September 8, 2008 Share Posted September 8, 2008 The water possibly hasn't helped either. Check for loose connections, which by their nature are problematic, but which also may have allowed water, displacement/cleaning fluids in or anything else which may block the connection. It's worth cleaning out all the block connectors while you do this anyway and adding a little silicone* lube to keep them clean/help the connection. *I think this was the stuff. Mind is a bit blurry today as I was at the sauce last night Link to comment Share on other sites More sharing options...
77500Xs Posted September 9, 2008 Author Share Posted September 9, 2008 UPDATE: Got her back running! After hours of tracing and testing I finally came across the problem; a faulty fuse connector. I went over and over that fuse and connector not thinking to test it because the appearance of the fuse was fine. I then tested the input/ output and there was no power coming out. Reconnecting a new on one and she fired up! The connector was actually bad. This was the red/orange wire with a single fuse loop off the main fuse block underneath the seat. Engine still cuts out when turn the h/bars fully to the left. Jim, I tried tracking the wire loom checking for breaks or tears; nothing visually stands out. How come I can still start it via kick start but after it cuts out I can't start it electrically even though it turns over? Link to comment Share on other sites More sharing options...
77500Xs Posted September 16, 2008 Author Share Posted September 16, 2008 Well after some more hours of tracing and testing I still have not found my electrical issue with the ignition cutting out while running. I even replaced the ignition switch with a used one hoping it was faulty but no such luck. I can kick start it right back up after it cuts out but for some reason the electric will not start the bike; it will crank and crank and sounds like it wants to fire but doesn't. After it cools, or about ten-fifteen minutes later it will fire up. Is there anything on the bike that once over heated will not allow you to restart via electric start? I did notice that while idling and trying to diagnose the cut-out some of the wire harnesses were getting really warm (ignition switch harness and plugs under the left side cover)...is this typical? This weekend I was cruising and twice had to pull over because the bike just cut right out. I really enjoy this bike being a first time owner of a classic Yamaha; good power and great handling, I just wish it ran better. She runs great at 1/2 to 3/4 throttle when the mains kick in but at 1/4 throttle she surges, hickups and pops only out the right side muffler. After a while of riding it stops popping for the most part but then gets the infamous high rev when trying to idle. I did notice the carb boots are worn with some cracks in them. Previous owner says the carbs were just rebuilt. It also has a new electronic ignition and almost seems like the timing is off by the way it runs; is this possible with the new ignition? Could the new ignition also be causing my starting problems? I truly love this bike and want to get it running correctly.....I just don't know where to start. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted September 16, 2008 Moderator Share Posted September 16, 2008 sounds like coils are heating up and failing. check your manual for the OHM readings Link to comment Share on other sites More sharing options...
77500Xs Posted September 16, 2008 Author Share Posted September 16, 2008 sounds like coils are heating up and failing. check your manual for the OHM readings Thanks for chiming in Drewpy! I've been spending most time reading your replies from related posts; awesome dedication. Sorry but I forgot to mention that they're new coils. Something makes me think the previous owner did not install the CDI correctly and now I'm trying to research that. I just don't know where to start. I know the carbs need some attention too but right now I'm just trying fix this damn electrical issue, or so I think... Link to comment Share on other sites More sharing options...
Moderator mervin Posted September 16, 2008 Moderator Share Posted September 16, 2008 Hey post some pics so i can see this bike please, for $19 ech coils from partsnmore are good i have em on my RD,s i believe mikes Xs sell them as well merv Link to comment Share on other sites More sharing options...
Moderator drewpy Posted September 16, 2008 Moderator Share Posted September 16, 2008 Thanks for chiming in Drewpy! I've been spending most time reading your replies from related posts; awesome dedication. Sorry but I forgot to mention that they're new coils. Something makes me think the previous owner did not install the CDI correctly and now I'm trying to research that. I just don't know where to start. I know the carbs need some attention too but right now I'm just trying fix this damn electrical issue, or so I think... I think you need to get back to basics in order to eliminate the cause: fully charged battery (and is charging), valves adjusted; timing adjusted, fuel flows into carbs freely, check all connections (use contact cleaner or ACF50) try pickup coil it should be 700+/- 150 ohms The high revving is due to a weak mixture on pilot jets/air leaks; check by spraying wd40 on the manifolds and listen to the engine revs. make sure the new coils are for electronic ignition, I'm sure that the ratings are different as its in the way the power to the coils are delivered. you really need to get the loom sorted, try a secondhand one off ebay would be the easiest option!! Link to comment Share on other sites More sharing options...
77500Xs Posted September 19, 2008 Author Share Posted September 19, 2008 Wow, am I getting lucky with this bike and troubleshooting! Tonight I tore her down, tested the whole charge system = check, spark plugs = check, coils = check. Good spark and plenty of fuel (def too rich) and she fires right up; turn the handle bars to the left and she cuts out. I started checking the juice at the switches (ignition and handle bar) and got consistent power while racking the bars back and fourth. Tested power at the coils with same technique and got alternating current levels, cutting out when racking the bar back and fourth. Culprit = bad connection plug AGAIN on the red hot wire which splices into brown coil wire and routes back down to ignition. Spliced a new one and we're finally free of the ignition cutting out!! Yes, finally! One problem down and a dozen to go! While I had everything tore off I siliconed my carb boots to hopefully seal off any cracks. They were pretty dry-rotted on the outside but nothing penetrated on the inside, so it seemed. Carbs were a litte dirty; looked like they were synced pretty damn well though but the intake ports were really filthy! Carboned and extremely dirty; not sure what I can do about that. Assembled everything back together and took her for a ride. Idle and throttle is still a little rough on the low end but she runs like hell when those mains take over. I no longer have those pops from the right muffler too! Seems to run alot smoother (not sure what I did) although it STILL CANNOT RESTART BY THE ELECTRIC START after it has been running for a while. One kick and she fires up; electric start will crank forever but will not fire. No idea.... Well at least I got the most important issue diagnosed and fixed without replacing parts; the additional tuning will hopefully get refined with experience. I can now TRUST the bike enough to enjoy on the road for a while. BTW has anyone heard of using seafoam to clean out an older engine? My buddy seafoamed his bike and got incredible results; hopefully this would help clean my valve ports and carburetors? Thanks for all the help and advice guys; drewpy and jimr. Link to comment Share on other sites More sharing options...
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