According to this User Manual on Page 53 (section 6-3) a Valve Clearance check should be carried out every 26,600 miles (42,000km). It also highlights any other maintenance that should be done and at what intervals.
I think checking is relatively simple (assuming you are handy with a toolkit.
I found a site that gives this method of checking your valve clearances, see if you think its within your skillset
- Remove plastics
- Drain oil (not required but less messy)
- Drain radiator (not required but less messy)
- Remove Seat, tank
- Remove air box
- Remove throttlebodies
- Remove radiator (if drained) or move down out of the way.
- Disconnect ignition wires leading to your coils
- Remove ignition coils
- Use a 5mm allen wrench to remove the value cover bolts and then remove the valve cover.
Checking Valve Clearance
You are now going to need to remove the rather large circle cover on the pickup coil cover.
To check the valves you are going to need a feeler gauge to measure
the distance between the cam lobes and the valve bucket. Try to find
one that is based on the metric system, in fact we are going to keep
everything in metric; because trying to figure out .005in is equal to
.127mm is a pain. Also have and sheet of paper out and a
Attach a 12mm socket the bolt that was behind the circle cover. With
the ratchet turn clockwise to rotate the cams.
NOTE: Never turn counter clockwise, this direction is against the
natural rotation of the engine and can do something really really bad;
I don’t know what exactly just don’t do it.
Rotate the cams until the two cam lodes closest to you (cylinder #4)
are facing up, and the value is completely closed.
With your feeler gauge check the valve clearance, by trying to cram
that piece of metal in-between the cam lobe and the valve bucket.
NOTE: you are measuring the exhaust side currently and the clearance
should be 0.21mm ~ 0.30mm so start with a 0.25mm feeler and go from
Find the largest feeler that will fit in-between. It is possible to
cram a larger feeler then that of the clearance make sure you don’t do
this! The feeler should just slide nicely in-between.
Now write down the measurement on you sheet of paper, make sure you
write it down corresponding to each value and cylinder.
Rotate the crank again, clockwise! Until you can check the valve
clearance for cylinder #3. Repeat the clearance checking procedure
then continue to cylinder # 2 and finally #1
Once you’ve finished the exhaust side more over to the intake side and
record the clearances there.