paulrever Posted January 19, 2013 Posted January 19, 2013 Spark plug cap is in good state i.e. no tears or holes, but now and then sparks are jumping across between the engine and plug cap. I noticed this today checking the electrical connections as the bike has been stalling. I thought the stalling, particularly when at low revs, was caused by water as it seems to happen after I wash the bike, or if soaked in the rain. This is what happened on Thursday, bike got soaked and stalled 4-5 times on the way home from work. Never used bike on Friday (had a day off work ), so back to top; discovered the sparking! I figure there should'nt be sparks jumping, so how do I stop 'em? Hopefully if this is fixed it might cure the stalling????? Thanks for any replies. HTR
Moderator DirtyDT Posted January 19, 2013 Moderator Posted January 19, 2013 On the YBR? Often caps are a screw fit into the HT lead and these work a little loose or a couple of stray HT wires become exposed. Electricity will always go to the easiest earth. See if the plug cap unscrews. Check any rubber for perishing. Cut 10mm of the HT lead and re-screw in the cap. Before you cut make sure that there is enough HT lead left to still reach the spark plug. If you want to be pedantic, run a little silicon around where the HT lead goes into the plug cap.
Moderator drewpy Posted January 19, 2013 Moderator Posted January 19, 2013 try a new spark plug too, as it might be fouling up/insulation breaking down
paulrever Posted January 19, 2013 Author Posted January 19, 2013 yep it's the YBR, does'nt seem to be any damage or perishing so i'll try cutting 10mm as you say. Thanks DT.
paulrever Posted January 19, 2013 Author Posted January 19, 2013 Thanks Drewpy, the spark plug looks good but if no fix from cutting lead i'll buy new spark plug. Process of elimination.
blackhat250 Posted January 19, 2013 Posted January 19, 2013 Carry a small can of WD40, When on runs , untill the problem is sorted,
paulrever Posted January 19, 2013 Author Posted January 19, 2013 Yeah gonna wait for to dry and spray wd40. Jumping spark now sorted, screwed plug on good and tight as it was very loose. Was about to test ride when started to hailstone, weather now set in don't think i'll be on road for a few days. Many thanks Guys.
Speedshop Posted January 23, 2013 Posted January 23, 2013 Once a lead or plug cap has broken down once, its scrap. There will be a microscopic trace of carbon left and it will only get worse and worse. New leads and caps are the only sure fix
paulrever Posted January 24, 2013 Author Posted January 24, 2013 Many thanks SpeedShop. Having got out again due to weather improving, you are absolutely right! The bike seemed to be O.K but........ New cap and HT then! Is copper HT the better option?
129crossplane Posted February 1, 2013 Posted February 1, 2013 This is a common factor when buying cheap boot/wires. I would just replace the wire/boot that is arcing. Im guessing this problem gets worse as the bike gets warmer or wet. As stated before electricity takes the path of least resistance and if it happens to be through the boot rather than through it than there ya go. I'm not much for "rigging" but rather fixing so thats why i say replace the boot. You can tes the others by either using an ohm meter to measure the resistance or a simple way is to warm the bike then spray water on them (one end to the other) and watch for arcing. Plug wires will tend to arc too so be sure they are away from or protected from heat sources. Watch for a gray ash looking area on the wire and boots as well
Speedshop Posted February 11, 2013 Posted February 11, 2013 Copper, we don't mess about with carbon film type as it degrades with use.
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