The only problem I am having with the NGK plugs is the CMR 10mm series. I had some pretty strange problems out them from misfires to completely shorted. I semi deconstructed one CMR6H the was shorted to find the short was occurring between the electrode and the insulator. It is like the porcelain had became conductive instead of insulating. I measure a 600kΩ on the one I took apart. I also had in a Stihl hedger that was causing dieseling shortly after start-up. That one even the dealer couldn't fix the hedger, just said it was fine.
But BB said v-belt are a problem right now with so many el cheapo on the market stating they are OEM spec'd when they are not even close. One vendor I use to use is getting them out of India. Rarely the sizes matched the stated size. With belts up to 2" short. So I switch over to Stens which sell USA made belts as I heard a lot good things about. Guess what even they screw from time to time as I got belt in that was to be 103" long and when I measured it before installing it was 104"; actually both belts were 104" as I had purchase two of them.
Now Kevlar and Aramid supposedly only have a 1-2% max stretch and should be used on any mower deck.
I personally I demand quality at a fair price. I really got to watch where I buy my parts now as too many vendors are simply lying about what they are selling. I even got strung by a couple Amazon third party vendors.The old saying "Buyer Beware" is even more true in today's market.
