toetoe Posted June 2, 2014 Report Share Posted June 2, 2014 i cleaned my bike today and as always after i have finished i start the bike and run it for a few minuets but today it ran for about a minuet and then started to pop and just cut out, i thought i could of got water in to some where with using a pressure hose but i have done the same thing every week and it has always been ok, after cleaning the carb, filter and air box i let the sun dry it out for a while but still no luck i then took the plug out and swapped it for an old one i had and it started on the first kick so i need to know a few things about spark plugs, first the plug i had in is about 3 months old so is that about the life of a plug in a trials bike, my bike is about 14 years old and here comes the silly question, can i kill a plug by water getting in from some where or was today just one of those coincidences, i took a photo of the plug almost as soon as it came out but it was wet with petrol and not dry like it is in the photo. Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 2, 2014 Report Share Posted June 2, 2014 The plug in the photo is carbon fouled. Do you leave your cold start enrichment on for some time? If not the carburation is a bit rich. Quote Link to comment Share on other sites More sharing options...
toetoe Posted June 2, 2014 Author Report Share Posted June 2, 2014 thanks for the reply but you will have to simplify it for me, (Do you leave your cold start enrichment on for some time) does that mean the choke and if so i can leave it on for about 10 seconds when i first kick it up and then after that the bike will start up first kick for the rest of the day and how do i alter the carb settings. Quote Link to comment Share on other sites More sharing options...
mokwepa Posted June 2, 2014 Report Share Posted June 2, 2014 Start up sounds fine but your bike is running rich. Fuel/oil ratio? Oil brand? And if thats fine then its carb ie: jets, needle hight etc. Quote Link to comment Share on other sites More sharing options...
toetoe Posted June 2, 2014 Author Report Share Posted June 2, 2014 i put about 12 ml per litre but i have just realised that that is about 80.1 which could be a bit rich, i think i read it on this site when i first started and thought it would be better being a bit rich with it being an old bike, do you recommend putting less in. Quote Link to comment Share on other sites More sharing options...
mokwepa Posted June 2, 2014 Report Share Posted June 2, 2014 NO...I personally dont. I personally run 66:1. Lets not start a huge debate. 80:1 is fine, its not that. What 2t oil are you using? Please dont say mineral? Quote Link to comment Share on other sites More sharing options...
copemech Posted June 3, 2014 Report Share Posted June 3, 2014 I think plugs often die that way. Allways replace mine at the first signs of hard starting as well. I recommend getting some heat into the motor and revving it out completely at least at some point during your ride, drag race style! Blows out the exhaust and burns the crap off the plug! Can't do that just putting! Quote Link to comment Share on other sites More sharing options...
lineaway Posted June 3, 2014 Report Share Posted June 3, 2014 You can foul a plug in minutes or less. If it is three months old not to worry. But on modern bikes correctly jetted they can last years. Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 3, 2014 Report Share Posted June 3, 2014 Cold start enrichment, this is the device that lets a rich mixture get around the throttle slide to enable cold starting. It is not a choke (although some people mistakenly call it a choke) The fouling on your plug is dry, ie it is excess petrol. If it were excess oil the dark parts would look shiny not matt. 10 seconds of cold start enrichment should not do this. Check your air filter is clean, then check the float height. Then give the bike a good hot run with a new plug. Only after that start to change the jetting if the plug is still dark. You can't rule out a failing HT coil, source coil, poor connection or other fault in ignition circuit. Try disconnecting kill switch first. 1 Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted June 6, 2014 Report Share Posted June 6, 2014 So many people confuse gas/oil mixture with being "rich." Being rich is the condition of having too much fuel in the air mixture. This can be caused by many things: incorrect jets, needle position or improper air/fuel screw setting, dirty air filter, plugged exhaust, etc. Adding more oil to the fuel actually makes the fuel/air mixture more lean. Dadof2 is correct in saying this plug is fuel fouled, not oil fouled. That plug can be reused after a good cleaning. When riding 2 strokes, I clean the plug before every event. I also carry a spare plug and a small wrench on the bike in case it fouls. That doesn't happen often but a fast plug change can get you back riding and finishing the event. Quote Link to comment Share on other sites More sharing options...
copemech Posted June 7, 2014 Report Share Posted June 7, 2014 I'm not telling you how to keep a plug working, but the VX plug I put in my "07 bike was in it when I sold it in "12. The Denso that came in my "12 bike is still in it, and it is nothing special, must be a decent plug, otherwise I would consider back to NGK! Do a syou like! Quote Link to comment Share on other sites More sharing options...
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