Jumping out of 4th gear

[Conzar]

Hello guys,

I would like to ask whether it sounds reasonable to you if only the 4 the gear on a 1998 CBR6 gearbox might be worn out.


What happens is you shift to 4th apply the gas and it will either jump immediately back to 3rd or hit a false neutral like the clutch is slipping, self select 3rd and then it will bang it back into 3rd.

I used to get this very occasionally before like i wasn't shifting into 4th hard enough, but now it doesn't want to stay in gear - except on downshifting and engine braking.

Only thing i have changed is the oil

Have i deaded the gearbox?
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Current ride: ZX6R 636 ------- Previous:KTM EXC 450 Supermoto --- ZX6R B1H --Hornet 600--CBR 600--SV650
11:05:35 Rob Fzs: i just wanna own an rd350 valve before they send us to war with durkadurkastan

[el_oso]

sounds like worn dogs if it's just that gear. If that is the case then yes. You could take it apart and replace, but it's probably cheaper to buy a new engine facotring in the cost of gaskets/seals and also time to do something like this.
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Duke 390
Previous: '05 XR125L | '96 XJ600S Diversion |'05 Suzuki GSXR1000 | '05 Honda CBR125-R | '97 YZF 600R Thundercat | '11 Honda CBR250
Car: Jeep Wrangler 4.0L

[RhynoCZ]

Do you shift gears firmly/strongly enough?

When you just stroke the lever, it'll jump down or into neutral on most bikes and older it is more easy it happens.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[Conzar]

I noticed it a few days ago and thought it maybe due to my chain being a bit slack, i then noticed it was just in 4th gear, new chain and sprockets are going on tomorrow.

I see this maybe a opportunity to slap a early Fireblade lump in it
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Current ride: ZX6R 636 ------- Previous:KTM EXC 450 Supermoto --- ZX6R B1H --Hornet 600--CBR 600--SV650
11:05:35 Rob Fzs: i just wanna own an rd350 valve before they send us to war with durkadurkastan