It's weird - BMWs of ALL kinds have always had this bar-vibe issue, even going back to the old air-head boxers. The old story used to be that the Nikasil cylinder bore liner (very, very hard material) was hitting a resonant frequency at 5-6k rpm. Not sure if BMW still use Nikasil on all the bores, but it wouldn't surprise me.mikeycee wrote: ↑Tue Nov 03, 2020 10:47 pm Yes - The Evotechs certainly did the job. On the 2017 onwards they fitted damping pads on the bar clamps in an effort to stop the issue but it really didn’t do the trick.
When I took mine out on the test ride, I didn’t particularly pay attention to, or notice any problematic vibes however I was just batting it about some back roads and just trying to adjust to the bike. Once I took ownership and got some proper miles on it I found out about the serious vibe issues around 5-6k revs. Numbing is the perfect term, IMO Almost intolerable for any long motorway distances as max resonance is at 5-6K revs - exactly at cruising speeds. My RR Was buzzy at 70mph, But this was on another level - I’m talking white finger territory.
The evotechs did the job perfectly.. Still a very tiny amount there, But hardly noticeable - It’s spot on now
Ohhh..... New Bike Day!
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Rockburner
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Re: Ohhh..... New Bike Day!
non quod, sed quomodo
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Rockburner
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Re: Ohhh..... New Bike Day!
My RR Was the same.... I’ve only owned that and this one though so not really had that much experience but that could well explain it!Rockburner wrote: ↑Fri Nov 13, 2020 4:59 pm
It's weird - BMWs of ALL kinds have always had this bar-vibe issue
I’m not even going to pretend to have the answer, but putting my logical hat on - It’s either a cheap cop out alternative to bearings, Or I think perhaps more likely to allow some tolerance maybe if the two arms are not adjusted 100% the same as each other. If someone let their adjustments drift a little from one side to the other on a pair of fixed bearings or similar it would likely knacker the whole job once load is put on it I would think.
But... Not really sure to be honest!
Re: Ohhh..... New Bike Day!
Actually ignore all that.... Just been out with the verniers and there is a taper on the linkage. The Arms must be either universal or fit certain types of linkages I guess and the rose joints allow for tapers & some tolerances I guess.