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R1 is AWESOME, but has issues
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39 Posts
Discussion Starter #1
In pursuit of why my bike refuses to start when slightly chilly, and per the suggestion of the service guy at the dealership,I followed the directions in the factory service manual, and this post: HOW TO: Check Compression, Valves, SYNC Throttle Bodies & Tune-up to check the valve clearance. I got the measurements, removed the shims and headed back to the dealership.

Never having adjusted shim-under-bucket valves before, I had no idea that I needed to keep track of what shim went to which valve. As such, the shop could do nothing for me, aside from offer a bit of advice.

So I reassembled my bike, placing the old shims randomly, so I could re-measure the clearances and keep track of what went where. That way I could actually replace any shim with the correct one.

All of the intake valves measured correct and proper - just the same as last time.

The exhaust valves, though, this is where it goes of the rail. I get no clearance at all on almost every valve. (Last time, most were 0.008.) I checked each one at least three times (rotated the crank between), but was only able to get (tight) readings on two valves. Not even the 0.002 gauge would fit. This leads me to think I pucked the fog somewhere. No clearance at all seems beyond the pale of tight valves.

Is this totally uncommon? Will I need to replace the errant, no-clearance shims and re-measure?
 

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“Rhinestone Cowboy” MF Doom
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11,031 Posts
Exhaust valve are usually the valve that go out of spec first. They get tight over time and this doesn’t allow the bike to breath properly.

I would highly recommend using somevery very good feelers.

Once you feel very confident with the measurements, just go ahead and replace shims as needed.

Be competent. You got it.
 

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R1 is AWESOME, but has issues
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39 Posts
Discussion Starter #3
I had an epiphany this morning on where I went sideways. When I pulled the shims, I removed the shim and bucket with a magnet, then picked the shim out of the bottom of the valve lifter bucket. To re-assemble, I put a spot of grease on the bottom of the valve lifter, then put the shim on that.

If I had been smart enough to read a bit more, one is supposed to place the pad (shim) first, then put the bucket in/on.

My plan at the moment is to re-align the K mark on the pickup rotor on the compression stroke, zip-tie and pull the exhaust cam, re-install the shims properly, then re-assemble and re-measure the clearances. I'll verify my several feeler gauges with my calipers, and maybe get the Yamaha ones if they're at the shop.
 

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52 Posts
I don't know if you're past that phase or not, but for valve clearances that I can't get my feeler gauges into, I automatically replace the shim with the smallest shim size allowed. Then I reassemble, remeasure, and then figure out the proper shim size and redo the job. If I still don't have clearance after going with the smallest shim, I just stop because that head needs to be rebuilt.
 
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