I will give you all the details summed up. 1993 CBR 600 F2 with 43,000 on it. In good running shape, new plugs, air filter cleaned, carbs cleaned, new V & H exhaust, etc. Here is the problem....

1) First gear...Bike runs good and strong all the way through first gear every time.
-Second Gear is the Problem-
2) Second gear...Will jump out of gear and into neutral around 5,000rpms if you are really getting on it.
If you shift out of first and into second and calmly ease the gas on you can make it all the way to red line in second gear.
So another words...in second if you ease onto the gas you will be fine, if you gun it coming out of second gear it will jump into neutral at 5,000rpms and you have to shift up and it can be forceful to do so at times.

3) Third gear...runs great all the way through.

4) Fourth gear...runs great all the way through.

5) Fifth gear...runs great all the way through.

6) Sixth gear...gear...runs great all the way through.

Any ideas that could lead this to a better diagnosis than it could be your clutch or tranny would be much appreciated? I am about to fix it myself, at least attempt too, it would help if I had somewhere to start once I get inisde.

 

sounds like a bent shift fork seems common for sport bikes to not like 2nd

 

Thanks, that will be one of the first places I check. Nice bike by the way, looks just like mine

 

If it makes you feel better I agree. My dirt bike did this, but it was due to an excessively worn shift fork, which as far as the geometry goes is pretty much the same thing, and has the same symptoms. Don't forget to check the oil sump screen for little 'presents' your transmission may have left you in your oil pan. Also, check 2nd gear's engagement teeth, because I'd bet they're looking pretty shabby after a few hard slip-outs. Of course those could be the cause as well, but shift fork problems are more likely I think.