I have a 91 F2 and rode it about 15 minutes with no issue. Riding through parking lot at destination some idiot blows a stop sign and I locked everything up and stalled. She wouldn't start after that. Start button did nothing but I noticed it did dim the dash a bit. Horn super weak and made sad little sound. Battery is new and fine BTW. I bump started it and it seems like it's missing a little now. WTF could have possibly happened that would throw timing off?!! Still wouldn't start. I'm sitting in my daughter's recital now and figured I'd post this since I'm stuck here for 90 minutes lol... And need to get the bike going to get home!

 

Rode home and it's dead as can be. Stalls at a stop and has no juice. I'll troubleshoot tomorrow and report back

 

Feels like I'm the only one reading this lol - I tested stator and r/r this morning and found rectifier bad. Swapped one from another F2 and bike started right up. Ran for 30 minutes and died again. #$@&!!!

So tomorrow I'll clean the R/R connections and try again... Hoping I didn't really smoke two rectifiers in one,day. The second was from a 93 with the heat sink fins.

 

Hi , sorry you haven't had an answer, could be you have a bad earth somewhere on your bike, as the horn is a direct 12vdc from the battery and you say that's weak, it sounds like a feed problem

Also Parasitic draw