sarandro Posted June 28, 2016 Share Posted June 28, 2016 Hi Everyone, This is my first post so be gentle!!! My 125 Virago blew a fuse...melted main fuses, all lights went off and it stopped. Trusty husband (with my help) replaced faulty fuses, checked all wiring for connections, put on new reg/rec, new TDI? We've checked the coils, the carbs have been cleaned, new fuel pump installed, new plugs, topped up battery. Horn works! (so not battery) lights all good, it wants to start, but spark is delayed ie I hit start button and about half a second later there is a spark. We are stumped and would be very grateful for any and all assistance Cheers, Sarah Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 28, 2016 Moderator Share Posted June 28, 2016 Clarify " it wants to start, but spark is delayed ie I hit start button and about half a second later there is a spark." what's the fine detail of this statement? wants to start? how do you know it sparks at all...is the plug out and resting on the engine? Link to comment Share on other sites More sharing options...
sarandro Posted June 28, 2016 Author Share Posted June 28, 2016 Hi Airhead, Thanks for your time...plugs out on engine, I press start, release starter button...one spark but delayed, like just after it should?? Then nothing It's a mystery to us!! Thanks Sarah Link to comment Share on other sites More sharing options...
neversaydie Posted June 28, 2016 Share Posted June 28, 2016 Its a v twin so there are two cylinders. Have you got the right leads to the right plugs? What do you mean by "then nothing". Does the motor cycle once then cut out? Link to comment Share on other sites More sharing options...
sarandro Posted June 28, 2016 Author Share Posted June 28, 2016 Hi Airhead, Yes all leads are in the right place, starter motor fine, I get one small spark,but engine won't run Hi, Never say Die I mean! Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 28, 2016 Moderator Share Posted June 28, 2016 did you try a push start AKA 'Bump Start' ? should be easy enough with a 125 twin Link to comment Share on other sites More sharing options...
sarandro Posted June 28, 2016 Author Share Posted June 28, 2016 Hi Airhead, Yes tried that also, nothing doing, anyway can't bump start every time (I'm only little) (I keep having to change my password every time I log in so sorry for the delay in getting back to you Thanks, we've also tried everything in manual twice as well, still no joy A bit of a strange problem it seems....S Link to comment Share on other sites More sharing options...
Noise Posted June 29, 2016 Share Posted June 29, 2016 When you say you changed the TDI do you mean the CDI (brains of the bike?) this "could" have blown in the power cut. Do you know what made all the fuses pop in the first place? Id say take both the spark plugs out and rest on the engine and see if they both spark, as if you only have the front one out it may seem to be delayed as it might be because the rear cylinder has only just finished its ignition stroke when you press the button. If your getting sparks on both cylinders then your starting issue could be down you fuel but im leaning more to electrical fault (worth a ceak tho). Make sure the HT leads are pushed right down onto the plugs and you feel good resistance on the HT cap as you push it onto the plug. Also does the battery sound strong when its turning over? if not then you may have a warped cell in there and be best to replace it. I know you say you toppe dit up but if it was killed in the power cut then your never going to regenerate it. Link to comment Share on other sites More sharing options...
sarandro Posted June 29, 2016 Author Share Posted June 29, 2016 Hi Noise, Thanks for the reply...(him indoors was in the 1st RTR, has a divvy and likes metal etc!!!) Don't know what made the fuses pop in the first place... We've changed the CDI unit, battery seems fine,, put in new plugs and tested against engine and checked the HT leads and caps Maybe I should get a new battery and see what happens Today we're going to try coils from another bike even though the ones on the 125 seem OK It's baffling!!! Thanks, Sarah 1 Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 29, 2016 Moderator Share Posted June 29, 2016 Battery. Has enough grunt to turn the motor but not for a spark. You give up. Let off the button and the coil finally gets enough energy to discharge. (Spark). Batteries can be tricky buggers. Lights and horn is no guide to battery health. 10v will turn the motor as well as lights and horn but the cdi will sulk and wait for 11, even 12v before doing anything. See what the voltage is cranking. And immediately after cranking. 2 Link to comment Share on other sites More sharing options...
sarandro Posted June 29, 2016 Author Share Posted June 29, 2016 Thanks Cynic, going to try a new battery and see what happens This is my first bike and I'm learning all the time...finding it very interesting but frustrating Husband says what makes a proper biker is knowing as much as you can about your own machine Hey ho here I go!!! 1 Link to comment Share on other sites More sharing options...
sarandro Posted June 29, 2016 Author Share Posted June 29, 2016 OOOOOHHH!!! Not battery, tried a new one off husband's divvy, no difference. Still stumped, any more ideas very welcome!!! Going to get bacon now as it is always better after bacon! Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 29, 2016 Moderator Share Posted June 29, 2016 Ok. This is more out there. Crank the engine externally without the starter. Pull the plugs and with the rear wheel off the ground spin it and see what spark you have. No load on anything then just cdi dont use the starter just ig on and spin the wheel. Idealy in a lower gear. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 29, 2016 Moderator Share Posted June 29, 2016 why did you change out the cdi? Link to comment Share on other sites More sharing options...
sarandro Posted June 29, 2016 Author Share Posted June 29, 2016 Hi Cynic, No spark,we think it's probably the replacement CDI and have sent it back the lad, he said he would send us a different one to try. We tried doing all our tests in the dark and noticed an errant spark from the coil to the earth at top of frame when we switched on the ignition, which shouldn't happen. I noticed an old post from Design?? which showed how to fix the CDI unit yourself, but don't know how to test the diodes with a multimeter. Seems the back cylinder isn't working (was always dicky, now we know why!) Hi Airhead, We changed it because we thought we had tried everything else Anyway, if it's not the CDI what else could it be?? Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 29, 2016 Moderator Share Posted June 29, 2016 What else could it be? I have been on this forum long enough to have seen that question followed by. 'Doh found it it thought i had (insert something simple) but didnt.' A lot more often than you might think. 4 Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 29, 2016 Moderator Share Posted June 29, 2016 I'd investigate the HT coil sparking to ground some more...do some more in the dark tests to see how much it's doing that...it shouldn't happen...ever! Try cutting a centimetre off the end of both HT leads where they join the plug caps 1 Link to comment Share on other sites More sharing options...
KevtheRev Posted June 29, 2016 Share Posted June 29, 2016 4 minutes ago, Airhead said: I'd investigate the HT coil sparking to ground some more...do some more in the dark tests to see how much it's doing that...it shouldn't happen...ever! Try cutting a centimetre off the end of both HT leads where they join the plug caps And make sure the coil is getting a good earth , scrape away paint if you have to . Link to comment Share on other sites More sharing options...
sarandro Posted June 29, 2016 Author Share Posted June 29, 2016 Hi Guys, Thanks so much for your time....just remember that this is my first go at sorting out my bike, I'm probably going to ask a lot of stupid questions in the future too!!! Done all the HT leads this afternoon...coil is getting a good earth.... Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 29, 2016 Moderator Share Posted June 29, 2016 have you got a workshop manual? Link to comment Share on other sites More sharing options...
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