back firing

[Guest]

So after getting some electrical issues sorted out with a new set of dyna 3.0 ohm coils and an sspb from posplayr and oil leaks sealed up, i hooked up my bench bottle to tune the carbs due to a hanging idle, and got that sorted i went for a test ride. Not far into the ride (thank god it was just a mile or so out) the gs650g started backfiring quite loudly around 4k rpm and would stall if i pulled the clutch without any throttle applied either idling down the road or at a stop and running really rough. It back fired hard enough to pop the petcock vacuum line. Got home and checked the wires, all connected and on the correct plugs, but noticed the coils were quite warm, around 150° or so on both, is that normal? So what things should i look at for possible causes?

To rehash on the bike, it's an 81 gs650g that is mostly stock, minus the sspb, turn out 4-2 pipes, drag bar, and diy ignitor.

I had to drop out the motor to fix the trans last fall and got it back in frame i think around april or so and have been sorting through issues as time and funds allowed. While the motor was out, i did the valve adjustment so i'm good there. I also fully stripped and dipped the carbs as well as per the ever popular tutorial. And the manifold o-rings are brand new

[tom203]

Still got the stock mechanical advancer? Make sure it moves freely back and forth. Sounds like your timing is too advanced at times, but maybe your dyi is overheating . Have a another go and see if it behaves ok till things get toasty.

[60ratrod]

I did notice the housing on the diy was kinda warm. don't know why I didn't think that was relevant, other than maybe residual heat coming from the motor. I really wish I could just get a good working oem ignitor. every oem ignitor I have gotten has been crap. right now I have it mounted under my battery tray since that was about the best place I could find for it to fit and seemed like it had enough airflow

[tom203]

You already got the dyna 3 ohm coils, might as well opt for the dyna ignition and eliminate the stock ignitor and pickups. The dyna plate needs a touch of cutting to clear the oil sender unit- bunch of guys have done this recently.

[60ratrod]

which dyna s do I need to look for? dyna's site is very vague

[tom203]

You got the ND ignition , so this should be the Dyna you want. The 650 isn't listed because they did not think you could grasp notching the dyna plate!

http://www.z1enterprises.com/ItemDetails.aspx?itemDescription=Dyna-S+Ignition+DS3-2+GS+fours+%28w%2fND+ignition%29&item=DYDS3-2

edit: someone recently posted a pic of notched dyna plate, but I can't find it.

[60ratrod]

YAY (proclaimed in a sarcastic manor)! Another hold back to getting my beloved Shelah back on the road. Well, i may have spare funds from this paycheck.