Alright Guys.
I have a 1993 Honda CBR f2 600. W/ k&n ait filter, yosh pipe, stg1 jet kit. I was recently burning up plugs so I cleaned my carbs, checked coils. I had River city honda ( a shop in our town syn the carbs) bike ran 100% better. Now after 2 weeks it is missing horribly. When I first start it does fine, No missing after about 10-15 min it starts missing to the point I can't get the bike over 5k it just surges back and forth,It will free rev ok sounds odd Tho. I Swapped the coils and CDI box (Extras that came with the bike) same deal. I pulled the tank off the bike, to check the petcock under idle and starting. It dumps tons of fuel ( is this normal seems like a lot of gas for such a small motor, the spring in the petcock is really light almost no pressure at all to push it, I can not blow threw the petcock freely, without taking it apart again is that normal?? I started the bike after 5 min of being off, with out the tank to check some wires, again revved perfect all the way to 13K no issues). This is very aggravating for me, I am a Motor builder for a dyno shop in my town and I am good with motors. But all the normal things to check for a “car” are working fine. This is my first bike and I am new to this world. But for $70 an hour to look at the same things I can. I thought I would see what you guys thought. Thanks a bunch

 

I have read about the stator on these bikes causingproblems. I dont know much about it myself, but there have been some Q&A sessions on here on the issue. Do you suppose the plug wires could be breaking down under load or after getting hot? Seems strange to be fine for a couple of weeks and then go south again. Runs well until temp comes up makes me think something is getting too hot.

 

Yea thats what I thought gauge was off cause it shows fine, motor never gets to hot to burn u or anything. I change the t-stat just in case and put new anti-freeze in it. My lights flicker at idle but thats it battery never dies or anything. Could a battery do this?

 

Could this be the rectifer???? That piece it selfs gets Extremely hot the wires stay cool but the rectifer gets pretty warm. Could it be burning up and thats why it does so bad the longer I run it without letting it cool????

 

everybody as lost as I am???? put a new batt in today same thing.

 

I'm really not sure. I'm guessing that its something electrical related. I would try replacing the rectifier I guess. The headlight flickering at idle is interesting, pretty sure its not supposed to that. Basically all one can do is just start throwing money at it and see what fixes it, and I'd start with the rectifier since you've already traded out the coils and CDI box.

Something else I just thought of. If you open the tank immediately after it starts doing its bogging and stalling and whatnot, does it make a wooshing sound? If you're pinching a vent or vacuum hose it could be starving the engine of gas after the carbs can no longer overcome the vacuum.

I'll try to keep thinking of things that could go wrong, see what I can come up with.

 

I'll check that to cause if I let it idle for a bit it does fine as well, Just check my coil wires from the coils to the cdi box there good not getting hot I ran new ones anyway same thing. I unhooked the rectifer same deal this is a new batt so the volt never got to low hooked it back up same deal again I borrowed my friends rectifer of his 93 same dam thing I'll check that gas thing. I turned the tank sideways so i could watch the carbs work and they were spraying gas but I have no clue if it was missing at the time it only does it under a load. And each time its starts after a wot run threw the gears. hope that helps explain things. my rectifer is goning bad when i used my friends no flicker but the miss was still just as bad.

 

have you tried moving the needle up. I just put a dynojet kit on my 93 f2. It states in the troubleshooting that if you are surging to move the needle up(c-clip down), also said it wasn't uncommon to have to move the needle up 1 or 2 positions. If you want I can get a scan of the dynojet directions. Also I would replace that rectifier ASAP. I also just had to do that. It burned the wireing harness to. however it can also take out your battery and stator. It REALLY sucks being stranded![:'(] replace it before it goes, and save your semi good one as a spare. Just incase. Oh, also carry extra 30 amp fuses.

Shawn

 

u guys wont belive this. It was the dam plugs. I pulled them and they were lean and burned up. It was my fault I went with 2 steps up to a much hotter plug cause of the jet kit. Noob mistake new plugs stock ngk's bike ran fine again. I'm getting a new rectifier ASAP. I guess once it got up to temp and plugs got hot they burned to well cause it is doing fine now... I'll keep yall posted..

 

Haha, that sucks. Glad you figured it out and that it was something simple and cheap.