Just doing some pre spring checks. Found the oil pump minimum stoke had dropped to zero, no gap at all. I tend to follow the service schedule on bikes anyway but I guess they really weren't overdoing it with this one, it might be wise to check it more frequently.
A 0.25 shim restored it to the correct 0.2mm min stroke.
After a oil pump rebuilt, you need to setup the stroke at idle.
I've setup the stroke to 0.1mm using a feeler gauge.
When the gauge gets stuck be the washer when the piston goes in your are OK.
0.1mm is the absolute minimum, and it only goes smaller over time...
I'm leaving it at the upper end of the range on 0.2mm and just checking it more often.
When I bought the pump new still sealed in the Yamaha bag the min stroke was 0.3mm, I found it odd that it was supplied not in spec.
Quote from: Arrow on January 30, 2026, 10:19:45 PM0.1mm is the absolute minimum, and it only goes smaller over time...
I'll check this over time ;)