Is it really necessary to have the valve clearance checked on these quads? My quad never has any issues starting and runs nice (1500 km on it). Bike has to be torn apart to check the valve clearance and it seems like a very big job and not cheap to have a dealer do it.  How many of you have done this after the break in period as the manual suggests? If you did was there any adjustment needed? How necessary is this if the quad is starting and running just fine?

[2015 Z Force 800 53/Trail EPS]

One of the most critical things to watch and adjust on any solid valve train system is it's valve lash, which will change during break-in. If they loose enough lash to hold a valve open when hot, it will leak and burn the seat causing permanent damage. If they get too much the valve tops can peen or flat spots can form on the cam ramps or rockers. So yes, it's important that they stay in the listed range. After break-in if all is well they stay pretty much stable until the hard surfacing wears through but to start, all that is part of the break-in so...yes, it's easy...and it's just a 500 so it's also pretty fast once you expose the valve cover. My 800 had 1300 miles now but between new and 800 miles I checked them three times...and set them twice. The first time at 200 miles and it needed it. The second time at 500 miles it was in range but I was there so they were set then again. The third time at 800 miles they hadn't moved so I have left them alone sense. I'll check them again somewhere closer to 2000 miles.   

As NMK said you definately need to check the clearances as part of the break in service. I did mine at 500m and they have not moved since (at 3000) on 2013 C500.

Thanks for the advice! The bike is going in on Monday to check valve clearance and check clutch alignment and have a new belt put on (still puzzled as to why my belt exploded so soon).  A little late on the valve check (1500 kms) as break in service was done at 600 km, but better late than never I guess.