A few things arrives today, the straighter chain guide design to replace the scored one, and a used chain from a 2011 roadster to inspect (not to use).
I stopped by the Yamaha dealer, knowing they're one of the few using Ti intake valves with high valve check intervals on the R1-M to discuss my clearances. Generally his advice was shim them, check at 2,000 miles for rapid wear, if rapid wear occurs, new valves are indicated because the DLC will be worn through. I have a quote for the seats, $30 a seat through millennium, not bad. They do tappet boring as well....hmm.
The conversation drifted into "but why", so I explained the scenario. He had some very interesting information, potentially why the chain and guides were changed when the Roadster was introduced.
Below could be a load of BS, but it certainly makes sense:
Part of EURO 3/4/5+... Standards as most of us know, is noise, but not just exhaust noise, all noise.
When he was recently at KTM they explained to the techs that one of the tests they do is a coasting, idling, ride by of a mic. Then they target the audible sounds for noise reduction. One of those areas they were able to reduce noise, was the cam chain, by notching/shrinking the outer plate on the chain, as we have in the Roadsters, like the one I snapped.
Coincidentally the roadster was introduced not long after EURO 3 cam in effect, but more importantly, it went into production knowing EURO 4 was coming. The tech mentioned, that he's seen a lot of the notched plate chain on EURO 4 bikes as a sound reduction measure.
He also asked if our outer clutch plate was rotated 1 notch, also a sound reduction technique.
Food for thought.
