R18 VIBRATION

[JAMUSAURUS]

Hi Friends,
I did the valve service myself. I set it at the high end of the clearance and the motor had more perceived vibration. Set them again at the middle of the spec and the vibration was less. YMMV

Is this the case of the 3 bears?

So theoretically, the lower end tolerance will be just right?

 

[BobW]

Is this the case of the 3 bears?

So theoretically, the lower end tolerance will be just right?

Mine got smoother with racking up miles while routinely running up and down the entire RPM range. By 4,000 miles it was noticeably smoother and just kept on getting better 2-3X that mileage. While not a huge difference from min-max clearance when adjusting valves it is possible that one may notice a change in the clatter and perhaps a more consistent clearance across the board v. go-no go that could contribute to being perceived as "just right" with Goldilocks v. 3 Bears standards being applied......

 

[Scott Semone]

Hi Friends,
I did the valve service myself. I set it at the high end of the clearance and the motor had more perceived vibration. Set them again at the middle of the spec and the vibration was less. YMMV

Do you recall the settings? Was the high end closer to .3 mm and you final setting closer to .25 mm or .2 mm?

 

[LCRC18B]

Do you recall the settings? Was the high end closer to .3 mm and you final setting closer to .25 mm or .2 mm?

Yes. The original setting I tried was right at .3 (bought four, .3 feeler gauges from Max BMW thinking it would be fine at the high end of the spec, especially since it was the first valve check). Noticed that is seemed to be vibrating more, thought it was in my head, but eventually decided to do it again at .25 to see if there was a difference. IMHO, it's definitely smoother at .25.

Since then, I've been wondering if that's why some people don't notice a lot of vibration and others do. I still have a really hard time understanding and believing why such a small difference would matter.