21 replies to this topic

[Paul Minnaert]

Pete,
I just looked at the servicemotoguzzi site to be shure, it seems they didn't change it to roller tappets, When I look now it is just like the old ones. The parts catalog that everyone refers to, was downloaded from guzzi when bikes weren't even in production, so last minute they changed their minds and kept the old system. Only tappets for all engines from 2008-2011 have a new number: B014603.

[Skeeve]

What do you think that means? Just natural evolution – or did the tappets need a redesign because the current system isn't working or lasting well enough?

Natural evolution, most likely: noise standards putting pressure on MG for compliance, ZDDP being phased out of motor oil to keep catcons functioning. I think Pete has pretty much made clear that flat tappets function just fine, but may not make the regulation compliance goal(s) achievable going forward...

[pete roper]

My guess is that the roller tappets are coming. Perhaps the parts manual was leaked by mistake and is in fact for the MY 12 bikes that will no doubt be being built from about now? Who knows? I certainly can't see it being a *Hoax* of any sort, it looks like an official parts site link.

Pete

[luhbo]

On second thought: why should roller tappets be a quieter solution as the actual harmonic cams?
Maybe something like combined roler/hydraulic tappets. But then don't mention the weight of such parts.

Hubert

[gstallons]

The roller lifters are to stop cam lobe / lifter heel wear.

[luhbo]

No need for that.

[gstallons]

And less resistance since the it is rolling friction instead of rubbing friction.