hey guys. ive got an 1989 cbr 600 f1. its all types of held together but thats not the point. a few days back i had a small high side, max of 8 mph, leaving work. turns out that my boss had washed his truck and the water that had run into the street had frozen into a slick sheet of ice.

so i go off, the tail end slides towards the brake side, rear tire catches dry pavement and and slams against the ground on the brake side. so far i have a slightly sent brake lever, for some reason it actually improved the breaking power lol. a dent in the tank from where the bar end smacked it, and a broken bar end holder. im not sure what to call it but its the grey/silver tube inside the handle bar that you screw your bar end into.

anyway, after my crash and riding home, i quickly noticed that the bike didn't feel right at all. running rough, not sounding right, and just generally awkward feeling. after i got home i find out that my rear tire was slightly cocked causing it to rub on by rear brakes. after aligning that and taking it for a spin, it was much more comfortable since it wasn't dragging, but it still feels really down on power in the low rpm's.

before the incident my bikes average top speed was about 140, it wouldn't like to hold an idle at 1500 when hot, and was other wise great

now it can still reach 140ish, it feels under-powered around town, and doesn't get up and go very smoothly at all.

so here where i'm at. the two header tubes on the clutch side become warm but not hot like the brake side, i have spark on all cylinders and i have some pictures of the spark plug from cylinder one i just replaced thinking that it may be the problem.

other background, i just repainted the tank myself, my cooling system works 100%, and my fuel pump clicks like it should

anyone have any possible idea what my issue is? its looking like a carb issue somehow, i just had them rebuilt around July, but my mechanic said that the floats may be sticking for some reason or another. here the pictures of plug one. hope their not too big

 

looks like their burning hot, which further makes me suspect a fuel problem

 

It looks lean. Kind of hard to tell because of the deposits on the ground electrode/strap that seem to be fuel impurities. I would start by checking the air filters. After a crash you are critical of everything so it could have been sneaking up on you before. Problems like that happen slowly so that you may not notice them until you really pay attention.

 

If your still hitting top speed then its firing on the higher speed circuits. So it seems like your having an idle/low speed circuit problem. If it is fuel related and initiated by the fall my first guess would be that the fall may have agitated and freed debris in the tank or carbs that may now be clogging those those circuits (idle/low speed jets).

So I'd probably pull the carbs and inspect and/or clean them. I'd also check the needles to be sure they are still seated properly and havent lost a clip or anything that may have them sitting inproperly after the crash as well as the floats and float needles.

I dont think its electrical as the the inner and outer cylinders are paired and would likely be the way it would fail in that case, not lefts and rights.

So that where'd I start.

 

+1 on the low speed circuits and float level. I've seen float levels change from the shock of a crash.

 

ok, ill work with the carbs and see whats up. im not very good with them so the shops probably going to handle it lol.

 

Take a look through this thread, it talks about sticking floats. A mechanic that says they're sticking for "some reason or another" don't exactly instill a lot of confidence in his ability.

https://cbrforum.com/forum/cbr-600f3...5/#post1096494

 

Not sure what that comment refers too but anyway....

Float levels are most certainly adjustable and are meant to be set within a specific spec set forth by the manufacturer within about a 1/10 of a mm.

FYI.

If Im looking correctly, not knowing the range of years, the 600F1 requires the float level to be set at 13.7mm +/- .5mm

 

thats me saying something or another. hes more than qualified to work of any bike that i know of.