Hello all,

I purchased a 2000 Honda CBR600F4 about a month ago and I've recently gotten it onto the road and have been enjoying it for the last 2-3 weeks.

The only thing I have not been enjoying however is the fact that while in second gear and revving the bike up around 6000-8000 RPM, the bike will suddenly pop into neutral all on its own. It does it whether you're hammering the throttle or if you're light on the throttle. It is a potentially dangerous problem if you were mid-corner and it did it to you...

I have tried adjusting the shift linkage in hopes of that holding the gear in better, but it seems to have little to no effect.

I have also tried holding my foot on the lever while in second gear enough to hold it in gear but not too much to shift into 3rd. And it helps I've gotten 2nd gear up around 10 000 RPM this way but its even more dangerous because the gear will still pop out on its own but not all the way into neutral so the neutral light doesn't come on and then the gear suddenly re-engages as long as you don't move your foot and creates another potentially dangerous situation.

So I have the bike manual and if no one has any magic solutions to fix this problem externally then it looks like I'll be diving into a transmission re-build over this coming winter season. And I was looking for suggestions of where to buy parts for such a job.

Is there anywhere online good to buy such parts from? or will I be hitting the dealer just for what I specifically need when I have it all apart?

Is there some sort of transmission internals upgrade you can do to the F4? like swapping in stronger F4i internals or something? I really have no idea thats why I'm asking..

Also where are good places to buy parts from in general? Because I need to get new bar ends, clutch lever, some other little stuff (all damage from the previous owners... sigh..)

The bike has about 45 000 KM on it currently.

 

I've had two things on my bike effect gears, the original linkage was warn, fitting a new rear set recommended by the local dealer, cheaper and better than Honda std ones worked well. The second was unexpected, when the water pump blow, replacing it made the gears feel a lot smoother. But unlike your bike the only issue I've had is the odd, say once a week at worse, false neutral, normally when going to second when really on it.

I would recommend having a chat to the local bike shop, that's what I did when I had a strange whilst. Turned out to be the water pump which I then changed. The mechanic was very informative and didn't mind having a quick look and listen for me. But my gut reaction, for your bike, the box has gone. sorry....

 

hmmmm thats some weird stuff that happened to you.

but yeah i've been reading through the manual a lot and there is 3 things i am going to check with the shift linkage that involves pulling the clutch cover off and if those 3 things are all okay then it looks like the problem is internal and i'll be pulling the engine and fixing it over this winter

i need good sources to buy new gaskets from and stuff and is there anything i would be an idiot not to upgrade while i'm in there if i have to go in there?

 

dogs are rounded from clutchless shifting. seems to be common on these bikes. heres pics for a visual



these are from my bike that had the same issur as yours. and it started with 2nd, then 3rd started also. see how one side of the first pic is rounded? the dogs on the second pic are rounded also, both should be machined flat so theres no tendancy to twist apart from eachother.

 

so some a-hole of a previous owner was clutchless shifting my bike eh, what a waste...

so does anyone know if there is any upgrades or modifications that i should for sure do while i'm in there fixing this? also where did you guys buy your replacement parts from when you fixed yours? and what all did you replace?

 

i got a set of used gears on ebay from a parts shop. just replaced everything. it requires taking the motor out though.

 

Be well worth servicing the rear suspension when the engine is out. I did mine when I had to whip the head off, makes a big difference, stop the rear from hopping about too much.

 

Sounds like the gear box to me. Had the same problem. Here's how I solved mine

https://cbrforum.com/forum/cbr-600f4...-118852/page2/

 

Install factorypro shift star to ensure gear engagement for next time around. My 99 has the same problem. Pulled the motor back in January but been too busy dickin around with my other scootahs to rebuild it....

 

Thanks for the advice guys I've been looking at new gear sets on eBay and I think I'm going to pick up a set soon because the colder weather is coming in and winter is approaching.

I will definitely be doing the suggested factorypro shift kit upgrade thanks for that.

And the other thread that was posted, that is pretty helpful thanks for that.

But what exactly is involved with servicing the rear suspension is it something I can do myself? I just got the manual printed yesterday so I'm gonna look into it.

Another question I have though is I seem to be having a problem with the battery not being charged properly what is a healthy voltage reading to have when doing the charging test by holding the bike at 5000rpm? Because the manual doesn't really say what is a healthy reading.

Thanks again everyone!