Normal 0 false false false MicrosoftInternetExplorer4 Style Definitions table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:"; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Hi,

I have a 1999 CBR 600 FX and whilst investigating an annoying little vibration so I thought I would start with tightening screws, balancing the carbs and cleaning the cam chain tensioner.
Using the Haynes manual as a guide it recommended that before balancing the carbs you should check the valve clearances.
I have checked the valve clearances and the exhaust valves are within the tolerance stated in the manual but the inlet valve(s) clearances are half that of what the manual says.
The clearance(s) are 0.08mm but the lower limit in the manual is 0.17mm - the reason I have posted is because all the inlet valves clearances are 0.08mm almost like they have been set that way! Would there be any reason why the clearance is so small or is the Haynes manual simply wrong for my model of bike?

Any help greatly appreciated!

 

The manual is correct. I think somebody in the Honda factory needs to be fired. I say this because i have an '01 f4i that is exactly the same way at 16k miles. Actually 4 of my valves are actually so tight they are open the other 4 are at .08mm just like yours. I just hope the valves arent burnt or worst seated harshly in the head. I ordered a shim kit and will be putting mine back together this weekend. then I'll keep an eye on for awhile. If it is bad seats then it wont be to long and it will be out of spec again. I'm glad you posted this because ive been looking at all the other posts that say you dont need to check them till 30k miles or so, and this proves otherwise.

 

valves can seat or walk...

 

Ya I know but I find it hard to believe that so many out there are just fine at 30k needing little or no adjustment at all and then just a slight few are way out of spec so early on. It would appear they were misconfigured at the factory. Anything is possible though.

 

mine didn't need anything still at 38K. was still on the border.
are you bouncing off redline often or anything?

but yea it's a bit odd for it to get so bad so fast.