Reply To: No spark – GT250 Carby
SOLVED!!
I put a stupidly low bid on a crash damaged 2008 GT250R on NZ’s equivalent version of ebay and somehow won the auction! I bought the bike back last night and swapped the CDI, and bingo! Spark against the cylinder.
The engine I put in was from a wrecker, so I still wasn’t entirely sure if there were any issues with it. After probably 20 attempts on the starter and a heap of fiddling with the choke slide by hand (the carb isn’t hooked up to cables or airbox), she fired a little burp. From here it took another few minutes of trying and she finally started and ran.
Still not sure what the yellow thing does. It is odd that it isn’t noted on the wiring diagram.
When testing the wires and looking at the wiring diagram, it seems the CDI deals with igniting the coils directly as well as sending signal to the tacho. Is this signal what tells the tacho what revs you are doing or does that come from the magneto signal?
That hint on the tacho and magneto is a good one, I’ll have to remember that for next time.
Yep, I think the black wires are for a horn as well.
Your assumptions are correct Marcel, the clutch, side stand and pick up sensor were some of first things I checked off when I started. The regulator rectifier I still felt wouldnt cause a non spark event so I left that off my list for the time being. The CDI was definitley on the list of things to try but it was the out of spec resistance readings on the secondary’s on the coils that led me to belive the coils were the culprit. Spec states the secondary’s should be 5.4 – 6.6 Kohm but I was getting around 14 Kohm. When I tried the replacement coils and they failed, I checked them, and they also tested to around 14 Kohm. Whether that has an effect on performance at the upper end of the rev range, I’m not sure, but I’ll find out.
Now I can progress putting this bike back together..