I need to know the valve adjustment procedure and

VALVES NEED ADJUSTED

Factory assembled motors don't need as much breaking in as DIY overhauls. Whichever, the key things are

- don't lug the engine
- don't run at high revs for extended times
-change gears more often
-change engine oil and filter more often, say at 20 miles then 1000 miles then 5000 miles.

See also

http://www.popularmechanics.com/cars/how-to/a3113/how-to-break-in-a-new-car/
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Has something to do with you timing and valve adjustement. Get it tuned the way it supposed to. Or just get performance. Its hitting a flat spot because the valve are floating inside the case when it goes too fast and doesn't have the proper performance added to the inside components.Have to have the right components to fit together correctly for the exact way you want your bike to run.

I suggest a second opinion would be in order as everything he did for the tune up was not altogether necessary. I consider that as the car was running ok before I would not touch the carby other than to fine tune the idle mixture to emission requirements. Any problems with the distributor cap would have showed up as a miss and the rotor button would have to be really bad but again as it was running ok. My policy is don't touch what ain't broke.Power valves in carbys are there to give extra fuel when the vacuum falls off under acceleration and do nothing else. To accommodate a bigger alternator more adjustment on the idle mixture screw would be necessary at idle but as alternator barely charge at idle the adjustment would be little. The low compressions may be from pumped up hydraulic followers and I would discuss that with the original engine builder as to what hydraulic units he fitted. but again if it was running ok before what the hell. Yes get a second opinion for sure from the engine builder.

check your battery connections.

Spark plugs are carbon fouled black usually caused by leaking valve seals,bad oil control rings.The fuel flow, the fuel pressure, the fuel itself, the fuel pump, the fuel filter needs to be inspected.Also the oil needs to be checked.--------- If one of the valve is out of adjustment, it needs to be realigned, as it can cause the leak and this may cause spark plug getting black. --------- I agree that at present, motorcycle is running fine, but this spark plug getting foul black, is the indication to checked this above mentioned possibilities.--------- ---------- Get the valves and fuel system inspected by the local dealer or at local garages.They can inspect the valve and fuel system and do required tune up and adjustments.--------- This will help.Thanks.Helpmech.

Hello...from your comment it sounds like your bike needs a valve adjustment. The "hollow" sound in the exhaust and the powerband loss is usually a good indication of this. Have you had them adjusted lately? This first adjustment should be done at 5000 miles and then every 7500 miles there after.
The settings are:
Intake .003 - .005
Exhaust .007 - .009
Always set valves on a COLD engine.

I hope this helps...good luck with your bike.

The valve clearance is automatically adjusted be the hydraulic valve lifter. However Yamaha say there are times when the valve clearance needs to be adjusted manually. Basically to balance a pair of valves if they become misaligned (pretty dam rare) as they are operated by the one lifter. (eg Inlet pair has one hydraulic lifter and the Exhaust pair has one hydraulic lifter)

The recommend service / checking interval is 20,000 kms. (12,000miles approx) according to the manual.

I have 15800 miles on my 2008 and after speaking with a Yamaha service technician, he hasn't had one in yet that has required adjusting when he has carried out the 20,000km service. Infact he has had to adjust one as of yet even at 40,000kms.

It is a bit of a pain to do, as a lot of stuff has to be removed and the covers are a little tricky to get off.

Me, I am not going to bother until 24,000miles, as long as you change the oil and filter every 5000 miles my Yamaha guy recon it will be OK.

If you are going to do it yourself, you will need a manual as only one value has an adjuster and the other is a slipper, so they are not as easy to adjust as a pair of standard valves.

During break in, everything breaks in. Valves need to be adjusted,bolts loosen(check your engine mounting bolts),steering neck bearings need to be adjusted,carbs need tuning,etc. 600 mile check ups often include changing the plugs along with the oil. You need to go over the whole bike with a fine tooth comb, it's probably a motor mount bolt.

Try cleaning the rubber hoses associated with the idle speed stabilisation valve. If that doesn't help, try disconnecting the wiring plug from the same unit, if there is some improvement then replace the unit. You could also try checking the fuel warm up and cold start valves, these should give specific electrical readings on a meter at set temperatures, (I should be able to produce the relevant values and test procedures if you need them- let me know). It's possible that the injectors aren't opening at the correct pressure or that their spray pattern is poor. A fuel injection workshop should be able to service them for you. You could try running some injector cleaner through the system-you simply add it to the gas tank when you fill up.
Good luck, Bob.