EricV said:
@Dallera - I don't agree that the final drive compares to the shock in those terms. The shock is quite simple, piston, wipers, seals, disks, etc. The final drive is an assortment of gears with a much greater friction level and surface area.
As you pointed out, no one changes the oil in the stock shock. If it were that vital, it would be a user serviceable item like the air filter, engine oil, etc. I've seen the oil from shocks with 20k and 40k and there wasn't much difference unless a seal went bad and allowed contaminants in.
And yes, I have changed the fork oil. The first change is always nasty, but the next one isn't very bad. Something about that oil that Yamaha uses from the factory perhaps? I don't do it every 10k like I used to on the FJR for that reason.
Always love it how you insist on misspelling my screen name, ErOc... ErAc... ErUc... ErEc... ErYc... ::025::
Don't know why, but it never fails that you do.
As far as rear shocks, or any shocks for that matter... I guess I've just had a lot more of them apart and on the bench in front of me than you, and believe me, what can come out of there can be incredibly nasty - much more so than fork oil - and even so after very little use.
As for your lackadaisical suggestion about the rear shock maintenance that "If it were that vital, it would be a user serviceable item like the air filter, engine oil, etc....", one more time - you know better... ::005::
The only reason most manufacturers seal the rear shocks on their bikes and make them *throwaway* replaceable items, rather than owner serviceable ones, has to do with the high gas pressures contained within them. The manufacturers don't want owners trying to work on stuff with very high PSI levels for simply liability reasons, and they also know the average "Eric" out there doesn't have high-pressure inert gas bottles sitting in their garage's, much less a proper way to charge a gas-emulsion type shock like they provide on the Super Tenere. Of course, most of the good aftermarket rear shocks use a bladder or floating piston for gas separation not just for the performance advantage they provide but also for the ease of maintenance and re-charging they provide versus emulsion types.
Odd, too... The Japs use the same quality oil in their OEM shocks as they do in their front forks, and you seem to feel a need to change that - and early - yet you feel no compunction or reservation in ignoring your shock (as well as recommending that others do the same) despite the fact it has to work far harder than the oil in your forks and there is a whole lot less of it to handle that stress, wear, pressure, etc.
But go ahead... Bury yourself deeper. It's fun to watch!
Dallara
(that's D-A-L-L-A-R-A... ::025:: )
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