First no question is stupid, it would be stupid to not ask and use the wrong spark plug.
We advice a NGK DR8EA, you should keep the gap between the electrodes of the spark plug at 0.7 to 0.8mm. Clean the spark plug at the first 1000km with a small metal wire brush and again at 4000km. The spark plug should be replaced every 8000km or when the electrodes of the spark plug are damaged.
You say that the spark plug is a NGK DR8EA I see D7EA in the book provided with.
Why the difference?
What is the best?
The NGK DR8EA and the DR7EA are very similar spark plugs, both have a 12mm thread size, 19mm reach, 18mm hex size, gasket seat and both are resistor based.
The main difference between the NGK DR8EA and DR7EA is the heat range, the DR8EA has a heat range of 8 and the DR7EA has a heat range of 7. More about the heat range classification can be found here The Spark Plug Myths Busted.
Both spark plugs are what you can consider as traditional plugs and are constructed for longer life and performance. The ceramic top prevent flashovers, and for both spark plugs NGK uses pure amina silicate for its ceramic insulator. The spark plug are equipped with a solid copper core and are triple sealed to aid in heat removal and preventing leakage.
Another question, is it possible to increase the maximum speed of this bike?
If yes, how?
It is a 200cc, I barely reach 110-115 km / h, I'm faster with my 125cc.
The simplest way to improve some performance is by making the engine breath and exhaust easier, so you can experiment with the airbox / air-filter and exhaust system. Of course you cannot expect much performance gain without spending some money.
Much better performance will you get by replacing the camshaft with a more aggressive one, and increasing the size of the carburetor... of course all this will make you Keeway RKV200 much less fuel efficient. Also changing the camshaft and the carburetor will be not cheap, and most people will just upgrade to another motorcycle if they need better performance.
Je pense bien que ça va me couter un peu d'argent, mais je ne pensais pas atteindre 160 km/h non plus.
un petit 120-130 km/h serrai déjà un plaisir.
Le magasin où j'ai acheté la moto me dit de changer le CDI, mais en fesant ça je perds la garantie. Par contre, aucun souci de garantie si je change tout autre pièces ( pot d'echappement, carburateur,...)
I think though it will cost me some money, but I did not reach 160 km / h either.
a small 120-130 km / h already shook a pleasure.
The store where I bought the bike told me to change the CDI, but by causing it I lose the warranty. By cons, no hassle warranty if I change any other parts (exhaust muffler, carburetor, ...)
Yes, it's true. By modifying your motorcycle you're likely to lose the warranty. For that reason most people modify there motorcycle after the warranty expires. What can be a bit long with a Keeway as I believe it comes with 3-years warranty....