Joatmon
New member
A buddy and I both put Wiesco pistons into our phazers and BOTH run great but have a noticable "slap" or light "knock" sound. He disassembled his last night and rebuilt it with all new Yamaha gaskets and double checked everything without finding anything wrong....fired it up and still the same noise...we can't figure it out...anybody have any idea??
tedgoesfast
New member
does it change when motor warm what is your piston clearance ring end gap also
Yamaha Nutz
New member
too much clearance should be .004'' on the phazer with a limit of .0055 if not you will be taking a chance of the skirts breaking then you will have bigger problems wiseco pistons are never a first choice for me i thing they are over priced junk
Joatmon
New member
Thanks guys, it seems that the clearance is just a little too much. I bought a Y-1 cylinder from ebay and put it on a Y-2 phazer, and thought that might be a problem but it doesn't appear to be. I calipered the bore and it came out stock, but i never measured the wiseco piston. Same with my buddy. This appears to be a common issue. Thanks Yamaha Nutz, I'll bet thats it....junk...should have known better...
mrmaxman
New member
The "slap" does get less noisy as engine warms up.
tedgoesfast
New member
too much clearance