SByota
New member
I just got the valve cover off my newly acquired 2005 R1 and checked the valve clearances. I have checked/adjusted the valves on several different moto’s (CBR 600, FZ1, YZ426) and have never seen this situation before. The center intake valve measured at .37mm, WAY bigger than the spec (.11-.20mm). All the other intake valves were .15mm and all the exhausts were at .23mm.
I pulled the intake cam and it looks great. I measured the cam lobes and it also measured all to spec. The bucket and valve tip looked fine and the shim I pulled out was a Yamaha 2.00 mm. I replaced it with a 2.20mm to bring the valve clearance back into spec. I ran out of time to measure it with the new shim, but I have no doubt it will be good. I also looked down into the intake and the valve/seat didn’t look any different than the other intake valves.
I must have spun the engine around 10 times and rechecked that intake valve over and over again. It measured the same every time. I have never seen a valve that out of spec in the “wrong” direction. I know that the valves/valve seat generally wear in the valve seat area and the clearance gets smaller over time.
Has anyone seen anything like this? Is there something I might be missing? The bike has 13.5K miles and an unknown service history. I wasn’t been able to ride it, but it started up fine, idled good, and revved freely with no strange noises. The bike sat for three years near the beach before I got it. It has rust/corrosion some of the outer surfaces, but the inside of the motor is unremarkable. Maybe just a bad day at the R1 assembly line?
I pulled the intake cam and it looks great. I measured the cam lobes and it also measured all to spec. The bucket and valve tip looked fine and the shim I pulled out was a Yamaha 2.00 mm. I replaced it with a 2.20mm to bring the valve clearance back into spec. I ran out of time to measure it with the new shim, but I have no doubt it will be good. I also looked down into the intake and the valve/seat didn’t look any different than the other intake valves.
I must have spun the engine around 10 times and rechecked that intake valve over and over again. It measured the same every time. I have never seen a valve that out of spec in the “wrong” direction. I know that the valves/valve seat generally wear in the valve seat area and the clearance gets smaller over time.
Has anyone seen anything like this? Is there something I might be missing? The bike has 13.5K miles and an unknown service history. I wasn’t been able to ride it, but it started up fine, idled good, and revved freely with no strange noises. The bike sat for three years near the beach before I got it. It has rust/corrosion some of the outer surfaces, but the inside of the motor is unremarkable. Maybe just a bad day at the R1 assembly line?
