So I bought a used CBR f4 about 6 months ago (give or take) she's been running just fine. I've done several 500+ mile trips on her. The only mechanical issue I've had is cam chain noise so obviously I need a new CCTV. Today I was riding to my wife's work to drop off a 'care package' and on the way to the freeway (about 3 miles) everything was great. As soon as I accelerated onto the freeway I noticed that the higher RPM range was feeling a bit weak and then as soon as I noticed, the bike started to bog down and die. Luckily I pulled over but she absolutely would not start. I called a tow truck and was waiting and decided to try and turn her on one more time a viola ! She turns on..... And she made it all the way to my destination as if nothing happened. Some things I noticed are 1.I felt some heat under my seat (but the thermo read fine and the engine didn't seem any hotter than usual when I put my hand near it) 2. A burning smell that dissipated quickly 3.I touched the heat sink in the tail section within 3 minutes (I think its part of the rectifier) of breaking down and it was cool to the touch and 4. Fluids all looked good. Oil was a nice color/level , coolant was as green as always (water wetter)....


So is my assumption on thinking it may be an electrical problem warranted ? Would a bad rectifier cause this ? The only reason I even assume that it may be that is because I have heard of bad rectifiers on cbr's and the burning smell/heat that was coming from the bike but the fact that the heat sink was cool kind of points me away from that..... Any suggestions or ideas ? Thanks in advance guys..... Help !!!!!


I forgot to add that the previous owner did drop her and she has some cosmetic issues but there was no major or engine damage. The reason I wanted to add this is because the slip on does need to be replaced. Currently I have it ghetto rigged at the moment (don't laugh) with a hose clamp and sheet metal near were the slip on and mid pip connect..... But that has been that way since I first got it and I really didn't think / don't think that it would be the culprit. I just don't want to leave out any detail. Thanks guys.

 

Yeah, I'd start checking voltages of your battery off and while running. I'd also test the R/R, depending on what I found by testing the battery.

There are a couple of very good write-ups on here on how to check and what to check. Sometimes, you can visibly tell an R/R is going bad by seeing the connectors melting or connecting pins in the connector showing signs of heat.


Glad to hear you weren't stranded!

 

Thank you sir. Sorry for the long reply time. I've been unable to ride or do much of anything due to sickness for the last month or so. I'll def check everything out today and see if that's the ticket !

Thanks again!