blowback with green white

[Bevel bob]

Thanks Dct-Bob, From the earlier posts we know that the lift on my cam (measured) is 8.915in(1.244) and 8.418ex(1.226) with a base of0.893, and (without timing figures) you considered that it was a Grey Mach1 cam. However I thought that the cam had suffered wear and been cleaned up.I have not been able to reconcile the Mach1 timing and what I have found and I certainly did not suffer blowback when running a Mach1 many years ago. Perhaps this cam is an aftermarket grind,or a worn 250F1 profile,You can see why I thought it may not be able to be re-profiled to a Mach1 ---unless the base circle is also reduced.

[DewCatTea-Bob]

[quote= Bevel bob ...
" From the earlier posts we know that the lift on my cam (measured) is 8.915in(1.244) and 8.418ex(1.226) with a base of0.893, and (without timing figures) you considered that it was a Grey Mach1 cam.
However I thought that the cam had suffered wear and been cleaned up. "

____ Ohh, right,, I had forgotten about that, but I now recall us discussing your cam before !
__ Going by your lift-figures alone,, if your cam is a stock Ducati-factory camshaft, then I still maintain that there's no-other DUCATI camshaft-model that it could possibly be, other than a Mach-I cam.model.



" I have not been able to reconcile the Mach1 timing and what I have found
Perhaps this cam is an aftermarket grind,or a worn 250F1 profile, "

____ Your found timing-figures are quite-likely considerably off-mark, since (I gather) you took your readings with a set lash-gap of merely-just 6 or 7 thousandths...
Without checking with a trustworthy workshop-manual,, I believe that in order to find the actually-intended valve-timing figures of a M1.cam, the lash-slop (between rocker & valve) has to be set at .012", (as less gap will result with exaggerated timing-figures [as you've "found"] ).
__ So before reaching any related conclusion, you really should double-check your cam's timing with the PROPER-amount of lash-slop. _ (Otherwise [with less lash-gap], you'll be including the cam's 'clearance-ramp', [rather than only the real starting-point of the actual lobe-ramp], which doesn't count as part of the cam-lobe's actually-intended lift-ramp & valve-timing !)
Also, it would be interesting to also try checking your cam's timing with the (NON-factory) 1mm lash-slop standard, so as to see how it compares to that which Eldert & Nigel have found.


Hopeful-Cheers,
-Bob