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If my timing chain is loose, is it possible for it to jump timing while cruising at low rpm's? The reason I ask is I have this issue with my bike that it runs great for the most part but every so often it will mis or backfire when I am at 1/4 throttle and then when that happens the engine will start popping and backfiring from the right cylinder only. This only seems to be evident though when I am off the throttle coming to a stop; it seems like a timing behavior. After a few starts later, it will run fine again. If this is possible, how can I check and adjust my timing chain? I have a CDI ignition on my bike btw. Thanks.

Z1 Enterprises had the correct size. They special in vintage Japanese bike parts for any one that didn't already know.

Thanks for the response Drewpy like always.

Well guys, after doing some thorough research on the forums I think I may have adjusted my clutch too tight which is making my kick start not catch correctly. I rigged up what was left on the end of my cable to the clutch so that I could operate the clutch good enough to get into the garage. In the process I am assuming I may have adjusted it too much which is affecting my kick start now...? I hope so.. Does any one know if a 74-78 xs650 clutch cable will fit my xs500? I'm hoping to buy one off of mikesxs.com.

After putting about a 40 mile trip on my 78 XS500 today my clutch cable snapped as I shifted into 5th gear! Luckily I was only about a mile from home and was able to get back without stopping and a couple hard shifts without the clutch. I took off the right side cover to find the end piece of the cable broke away from clutch lever assy to the engine. Once I order a new cable it should be a simple fix. Now my issue is when I tried to start it back up via kickstart it wasn't catching! Could I have ruined the kickstart from the few hard shifts I made without using the clutch? I still had the right side cover off and foot peg while attempting.

Thanks a lot!! A response finally!!

77 500 xs: tried siliconing the intake mani's with no such luck. The bike idles great and has awesome throttle response when cold (no backfiring too) but as soon as she warms up I'll get the infamous high-idle and awfull low-end throttle response; also starts popping. I do have cracked and dry-rotted intake mani's. Will 650 Mikuni BS38 carb boots off of Mikesxs.com fit my Mikuni BS34's? I do believe mine are 38mm (not sure) diameter openings. If they will not does anyone else know of a reference or site I could get some new ones from? Thanks.

Should I be leaning for the turns during lower speeds and at take-offs or actually turning (the handlebars) for them?

Wow, thanks for all the great advice guys and gals. Ttaskmaster that was a great write-up, thanks. I have the clutch and throttle combination down pretty well as far as recognizing the "biting point". I'm still using the two feet approach when stopping and taking off; I would still like to break that habit though. Most times I take notice of putting my feet down too early when coming to a stop! It probably looks hilarious from behind as I probably look like the road runner trying to keep my feet up to the pace of the bike! Lol. I guess practice makes perfect... I normally do not have a problem when taking-off in a straight line, it's usually when making an immediate turn left or right from a stop. That also probably gives great entertainment to others! Lol. I don't think I'm using the handlebar steering properly yet at slower speeds as that gives a totally different feeling/control. Last night I was practicing a lot of this in an empty parking lot just trying to get more comfortable with the bike's actions and reactions. There's actually an inclined intersection on my daily route that I'm extremely paranoid to use because I already stalled once from a go on it. I had to push the bike off to the shoulder and re-start it; talk about an embarassing experience!!

Is there anything I can do to improve my balance when stopping and taking off? It always seems as though I need to go back and fourth when slowing down and taking off to keep secure balance on the bike. I was using one foot to balance but now am starting to use both feet when coming into a stop for better balance. I guess I am asking what most people are using for the best combination of braking and balancing when stoping and taking off. I have been riding for a couple months now and am trying to refine the smoothness in this process; it's a lot harder then what most non-bikers think! I have a 77 500 xs with vertical controls. Thanks guys.

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.

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...

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.

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?

Thanks again Jim, I'll check that out.