Ran these pistons for 2 years in my modified RD 350. Never had a problem. Before these pistons I broke 2 sets of cast pistons running up to 10,000 rpm. Wossner's could take 13,000 rpm's without a sweat. I'm porting another set of cylinders and will use these pistons again. I like that they cost less than Wiseco's and come with coated skirts. Wiseco's don't.
8075 Assembly // Yamaha YFZ350 BANSHEE-RD400-RD500 '73-'06
First time ordering or using Wossoner pistons.. promt service, excellent looking product.. will have to get to you about performance