Green White Cam

[DewCatTea-Bob]

" I have noticed some numbers on the unmachined area next to the lobes. There is the number three followed by a dot then the number five. Under the dot is the number eleven. "

____ I don't know what that may mean but, I've seen the same on other camshafts from stock w-c 350s.


" Intake lift = 9.7mm
Exhaust lift = 8.28 "

____ These lobe-lift figures are (still) consistent with only a G&W-cam...
And the exhaust-lift is too low to be that of an (unworn) 'F1-cam' type cam-grind. _ So it seems that your particular G&W is the more useful (for a 350) 350Mk3-cam.
Even though it's not as wild as the F1-version, it's still not the best choice of cam for best overall-performance with stock exhaust or other restricted mufflers.
A stock/mufflered 350 with a White-cam will (very much) out-accelerate a 350 with the std.w-c 350-cam (even without muffler!), while below mid-range RPM ! _ And stay about even during high-range RPM (unless the G&W-cam equipped 350 is unmufflered).
__ So for anyone who appreciates the type of power that a single-cylinder provides, and expects to do street-legal riding,, the logical best-choice for a cam, would then be the 'White-cam' !
____ I'm confident that Graham has now done the measuring of his cam, as best as can be done with his measuring-tool. _ And the figures he has obtained are correct for an unworn 350Mk3/G&W-cam. - (Keep in mind that it seems the Ducati parts-books do not clarify which cam the G&W color-code actually belongs to but, top-sources [like John White] have always referred to the G&W-cam as being the very same camshaft as the '250F1-cam' ! )
__ Back before the '80s, I visited a number of DUCATI-shops (all east of the Miss.River), and never found anyone who had a Ducati parts-book which covered the pre-1968 wide-case models, but I was once told that such a parts-book existed. - (Supposedly Berliner had one and sent their own machine-copies of it to a few of their top-dealers.) _ If anyone still has that particular parts-book/copy, (I'd expect that DomiRacer should've HAD one!), it should tell what the color-codes of those unique-cams are !


Hopeful-Cheers,
-Bob

[joe46ho]

Its been a long time since my last post on here, I have had a lot going on, severely injured my leg, had healing and rehab to deal with... I am now back to working on my 66' Scr restoration..

Reviving this thread from the dead i suppose, but I just recently found out while cleaning and cataloging parts on my restoration that my 66' Scrambler has a "red" mark 3 cam fitted to it. Any opinions on keeping this or swapping it out, I am not really concerned with the power so much as this is a restoration, and will not be ridden much. I have two spare cams, both violet, I could swap in one of these, or I could find a white cam to install.

any help is appreciated, thanks, Joe

[DewCatTea-Bob]

" Reviving this thread from the dead i suppose, "

____ It's of-course always perfectly okay to place a (related) post on an old thread that's been left dormant for a long-time ! _ However, considering this thread's particular/specific topic-title, you certainly could've started a new thread since your somewhat unrelated camshaft-topic is considerably different and a more unique & specific topic-matter.
__ If you had chosen to post in this thread because you had (logically) assumed that a White-cam & a Green/White-cam must be reasonably close enough, then it should be noted that such reasonable-logic doesn't apply in this case, as those two cams are near opposite-ends of the cam/valve-timing spectrum-range -(of 'mild' to 'wild'), from each-other.
The Red-cam however falls on that scale nearly midway between those two others, although more-so in the same class as the G&W.cam.



" I just recently found out
that my 66' Scrambler has a "red" mark 3 cam fitted to it. "

____ What do you think is the explanation for that ? _ Did the previous-owner acquire the Red-cam for the Duke-project, or what ? _ Cuz otherwise, it could be that your entire cyl.head is a Mark-III item.
__ How about a pic or two of iyour Red-cam, so I can then possibly confirm your camshaft-model ? ...
It would be best to see it pic.viewed from the threaded-end shaft-face and also a shot showing it's ex.lobe's profile (from the oil-inlet end).



" Any opinions on keeping this or swapping it out, I am not really concerned with the power so much as this is a restoration, "

____ There's not actually a real big difference in overall power-output between the Red-cam & a White-cam, except during RPMs over 6-grand when there's also no restrictive muffler employed. _ And when there is such an actual muffler employed, then the White-cam would provide a somewhat notable power-edge (over the Red-cam [with same ex.sys] ), at the lower-end of the RPM-range, (thus nearly cancelling-out the high-RPM power-advantage of the Red-cam, which thus makes the overall power-output of both cam-models to be roughly comparable). _ And-so also,, an un-muffled 250 with the White-cam will out-perform a muffled 250 with the Red-cam, throughout the entire RPM-range. _ However that's really not claiming very much, cuz whatever particular combo of ex.system & cam-model happen to come to be matched-up together, a rider-weight difference of only 10-pounds will taint & tend to overshadow any actual performance-difference (between 250-DUKEs) on the race-track,, so the choice of cam-type doesn't (solely) make a greatly significant difference.
__ A disadvantage of the White-cam is that, (in comparison to the R.cam), it makes the compression a little more difficult to deal with during kick-starting (because there's then more CCs kept within the cylinder, to be compressed).



" I have two spare cams, both violet, I could swap in one of these, "

____ There's virtually next to no-difference between the Violet & White camshafts, as (I believe) the n-c White-cam is merely a 'reground' version of the Violet-cam... Meaning that the White-cam is an ever-so-slightly hotter cam.grind, and the difference in power-output of those two camshafts is next to non-distinguishable (in a 250-engine).



" or I could find a white cam to install. "

____ Unfortunately, there were 3 or 4 DIFFERENT (but fairly similar) camshafts which all ended-up the 'white' designation and the same part-number ! ...
The original/first one was of the pre-1967 250-Motocross/Scrambler-models, and then-later there were 2 or 3 newer versions of the White-cam produced for various WideCase 250-Scrambler models. _ Three of the four White-cams* have fairly similar valve-timing & valve-lift.
Most-all of the w-c.cams have a smaller base-circle (which would accordingly require thicker v.shim-caps when installed in a n-c cyl.head [that's not yet been readjusted since removing it's original/n-c.cam] ). _ And a n-c.cam (with it's larger base-circle) will possibly not work in a w-c cyl.head that's had it's valve-seats significantly ground-down, because v.shim-caps don't (standardly) come much thinner than 2mm thick.
So it's really too-bad that all the versions of the White-cam have the very-same color-code & part-number !
(* It may be possible that one of the four 250-SCR.cams could have been given another color-code other than 'white', (such as 'brown'), but it stands to likely reason that they all ended-up with the same [white] color-code.)



" any help is appreciated, "

____ If your Red-cam is already removed from your cyl.head, then I'd suggest trading it for other parts you may need.
(It's my good-opinion that a Red-cam is worth about the same 'value' as about 4 White (or Violet) cams, [due to the substantial rarity of & high-desire for the Red-cam].)



Duke-Cheers,
DCT-Bob