Green White Cam

[DewCatTea-Bob]

" I've seen a number of cylinder heads damaged by using a metal bar to lock the camshaft. Usually, a chunk of the head casting comes off the top of the head. "

____ How very strange, as I've never heard of such a tale as that before, nor have I ever seen any such head-damage possibly caused from that ! _ (And how strange that anyone could come-across such results of more than one careless-mechanic! - Unless the same local forgetful-retard kept doing the same mistake over & over !?)
I suppose that such damage is possible if some dummy, who doesn't notice the LEFT-hand threads,, goes crazy with a sledge-hammer & extra heavy-duty impact-driver. _ (Especially if a bar that's too narrow is tried and without being extended fully inward over both rocker-arms.)
Also, I'm thinking that if over-tightening of the nut is attempted with just torque-strength, (no pounding), that the nut's threads will strip-out well before the head's top would crack.
__ I've always been able to get the job done (safely!) using a std.size breaker-bar (if not with just a std.1/4" ratchet-driver !)
And if Graham could not budge it while using an additional 2-foot extension-lever, without cracking the top of the cyl.head,, then that goes to show just how unlikely it would be to do such damage to the head while in the process of using a (suitable) bar to prevent the camshaft from turning along with it's nut !
__ Even so, it now seems that it may be prudent to exercise extra care when relying on the strength of the upper head-casting. _ And prefer the use of an as-wide-as-possible bar, as can be found.


" If using the proper Ducati camshaft locking tool doesn't allow the left hand threaded nut to come loose, it's probably better to cut the nut off.
I've had to cut a few nuts off like this. "

____ I have the Ducati-factory cam-holder/tool, but have always found it more convenient to do as I've instructed. _ (Since that factory-tool first requires removal of the left-side camshaft-bearing support-cover.)
__ I've done the camshaft-removal job from at least 50 DUKE-heads, and I've never had to destroy a cam-nut in the process ! _ (Although I have used a punch-tip on a couple of them [which already had punch-marks] before.)
So I really don't think it should ever be necessary to cut & destroy an otherwise good (& RARE!) cam-nut. _ (Not to mention possibly damaging the camshaft's threads, in the process of cutting it's nut.)


Hopeful-Cheers,
-Bob

[frankfast]

I've used a rather thin aluminum strap wedged between the bevel gears to remove that nut. I've always had success without damaging the gears or the bearings.

[DewCatTea-Bob]

" I've used a rather thin aluminum strap wedged between the bevel gears to remove that nut. "

____ I've seen a few hundred bevel-gears damaged by others using a thin metal bar to lock the bevel-gears...
JUST-KIDDING, fortunately! - (As those of you who've just read all of the above posts may have already figured.)
__ However, I actually have indeed come-across several upper bevel-gear pairs which had their teeth damaged anywhere between just being chipped, to completely massively destroyed,, mostly just on DUKE-engines which employed a (stock type) tach-drive. _ As it seems that the stock-type extension-cross has (relatively often) somehow gotten loose & between the bevel-gear teeth-edges and busts-off a piece of bevel-tooth that then also gets in-between the bevel-teeth and THAT then leads directly to the more massive-damage of the bevel-pair !
__ So I myself would never choose to allow a single-pair of bevel-teeth (alone), to ever be so unduly stressed by themselves like that,, for fear of possibly leading to later consequences, of the sort mentioned.


Bevelgear-Cheers,
-Bob

[frankfast]

As recorded earlier, my green/white cam and rockers are toast because of a broken shaft on the oil pump gear. I've now installed a pair of screw type rockers and a white cam from a 250 Scrambler. I took your advice Bob and can't wait to fire it up. I'm just waiting for my machinist friend to grind the scoring found on the inside of oil pump body. Since this bike was not a restoration project I tried to keep expenditures down but it still cost upwards of $500 to get it back to where it is right now. Ducatis are expensive to rebuild. Even though this is not a restoration, I'm sure that I've spent more rebuilding this bike than I could get back by selling it. It's definitely not for investment. I'll try a CB450 for my next project.

[DewCatTea-Bob]

" Then I can finally measure the lobes for ya. "

____ Which-ever the camshaft-model actually is, it ought to be a WideCase-type which all have cams that have base-circles which are only slightly larger in diameter than that of the main-body of the shaft itself. - (Unlike n-c model cams!)
The base-circles of the pair of cams -(a 'cam' is both the base-circle + the lobe) on the camshaft, may be almost exactly the same diameter,, while the cam-lobe's height (above the base-circle) may be up to 1mm greater for the intake-lobe than for the exhaust-lobe.
__ So when miking the pair of cams, try to find the smallest possible measurement for each base-circle, and also as well, the largest possible measurement (of the space) between the top-peak of the lobe and the base-circle (180-degrees opposite of the peak), for each cam.
Then subtract the base-circle measurement of the intake-cam from it's total-measurement, so as to get that cam's 'lift' figure,, and of course likewise for the exhaust-cam.
__ The results of this measuring of both cams will then allow specific identification of a (stock-DUKE)- camshaft-model.


FUN-Cheers,
-Bob

[DewCatTea-Bob]

" Intake = 9.67mm lift
Exhaust = 8.31mm lift
Wear doesn't seem to be an issue. "

____ With those figures, I'd expect there to be some wear (if your cam is a G&W/F1-cam, and especially if it was a 350M3 version). _ And in such case, the unworn edge of the lobes is where the readings should actually be taken from, (in order to obtain the original/intended cam-lobe lift-figures).


" From the limited cam data I have, it falls into the range for a Green/White cam. There seems to be quite a range of measurements for the G/W cams. "

____ Yes, it must be one of the so-called 'Green & White' camshaft-models,, however as I've long been trying to inform everyone, there are TWO different camshaft-grind versions which both seem to have ended-up with that same "Green/White" designation.
The original Green&White-cam first employed in most-all early wide-case 350s, have lobe-lift figures which are about 1/3rd.mm -(.013") greater than those of the 250F1-type G&W.cam -(which was also employed in later w-c.350s imported into the USA, by early 1969).
__ Directly below is a comparison-listing* of the valve-timing factory-figures for each of the two G&W camshafts...
* Intake: 65-BTDC till 76-ABDC ; Exhaust: 80-BBDC till 50-ATDC, for the 350Mk3-cam
* Intake: 70-BTDC till 84-ABDC ; Exhaust: 80-BBDC till 64-ATDC, for the 250F1-cam .
(For comparison, the M1/(Grey)-cam has corresponding-specs of: 62 - 76 / 70 - 48 .)
__ Since you're sure that there's no wear on the peaks of the cam-lobes, it then seems that your particular G&W.cam must be the F1-type, (which in my enlightened-opinion, is the G&W.version with the least preferred cam-grind !) ...
__ I was once told by another source long ago, that the intake-valve's lift by the G&W.cam is an even 10mm,, and incidentally, when the 1.04 rocker-ratio is applied to your intake cam-lobe's lift-figure, it then results in the expected 10.0mm figure !


" I'm sure with a bit more fiddling I can get the base circle measurement down below 21mm, "

____ So I gather then that you didn't find both cams to have the exact-same reading for their base-circle ? _ (Wasn't the intake-cam's base-circle any smaller at all?)


" Anyone have a White cam they don't want? "

____ While the 'White-cam' is a pretty-good choice for a street-legal 350-DUKE, the overall BEST-choice (from ALL of the stock DUKE-camshafts) for any 350, is the 'Grey/M1-cam' ! _ As while in a 350, it doesn't give-up much of anything, to either the White-cam's low-end torque advantage or the G&W-cam's top-RPM power advantage.


" If anyone is interested I can send them photos of the lobes. "

____ It would be quite nice if you would post your pix of such, added-on right to your above posting ! _ (Or within another [new] post, if you also have more text to add as well.)


DUKE-Cheers,
-Bob

[frankfast]

I'm very interested in your Green/White cam. I just purchased a very good white cam from and installed it in the bike but have yet to run the bike. It's in excellent condition. I would like to see pix of yours. You can PM if you want.

[DewCatTea-Bob]

" I just purchased a very good white cam from and installed it in the bike but have yet to run the bike. "

____ First I must finally say, it really kills me how all the new-boys (seemingly purposely) over-use the term "bike" ! _ And also seem to refuse to raise their DUCATIs out of the crowd -(of mere bikes), to the status of 'DUKEs'. _ That tends to make me think that the owner/member would just as soon have a Harley or a Honda, as their Duc-single. _ Thus it seems a fair way to separate those of us who just happen to have a Duc-single from those of us who actually prefer to choose to own one.
__ Bringing this up now doesn't have anything to do with this thread,
I've just been holding-back this out-burst until now. _ Sorry, I'll move this rant out to a more suitable place, later.

Anyhow.....

____ It would then be a real crying-shame to not also go-ahead & try-out your 350 while the White-cam is still in it, so that you can also become enlightened as to the substantial difference in compression and power-characters provided by that cam !
__ At least it's seeming that you may be trading for the G&W-cam version that's most like the Grey/M1-cam, and thus even more suited for use with your non street-legal exhaust-system.


Hopeful-Cheers,
-Bob

[frankfast]

It's too bad that the term 'bike' offends you as you seem to regard Ducatis as a motorcycle that transcend that description. I, for one, don't regard the term as derogatory. I've had many brands through the course of my forty years of motorcycling and have referred to them all as 'bikes'. I've also marveled at the engineering behind every one of them. Especially the older ones because they are usually the result of the genius of a single person. For that matter, I've had the privilege of meeting and shaking the hand of Dr. T himself during a tour of the Bologna factory. So I don't think that I shouldn't be lumped into a 'newby' category as regards Ducati motorcycles. After all I purchased my first one new in 1975 and have had many since then, including the three that presently reside in my garage. The older I get, the more I've become aware of the fact that Ducatis are not the only motorcycles on the planet although I still regard them as one of the best. They are just not sacred anymore. Enough said.
My effort to acquire a green/white cam is only in the interest of returning the motor to its original form. I don't doubt that the white cam would provide an improved lower end performance. That seems obvious given the specs on both. But since the bike is no longer a Scrambler but has evolved into a 'Roadster', perhaps the green/white cam may be more suitable.

[DewCatTea-Bob]

" It's too bad that the term 'bike' offends you as you seem to regard Ducatis as a motorcycle that transcend that description. I, for one, don't regard the term as derogatory. "

____ Nor do I myself think of the word 'bike' in any negative light, either ! ...
Back before the term "bike" became popularized by Harley-people, everyone referred to their motorcycle as a 'cycle' (rather than 'bike'), even myself,, as I bought my very first cycle -(bike) because it was a motorcycle FIRST and that it was a 'Ducati', was then a SECONDary consideration (at the time).
(After that point, every cycle I bought was a DUCATI because it was a DUCATI.)
So depending on who I would run into back in those early days, my DUCATI was either a 'cycle' (like I myself would always say back-then), or a 'DUKE', (which I back-then thought was kind-of a corny thing to say). _ I didn't adopt the term DUKE until sometime back in the '80s, after many of those who used to ask me why I don't refer to my DUCATIs as "DUKEs" instead of "cycles", began dying-off.
the __ I do think that DUCATIs are worthy enough to stand-out/transcend outward from the mass-crowd of motorcycles/bikes in general, to earn the term/name 'DUKE',, just as devoted Harley-owners feel that only Harleys deserve the use of the term 'BIKE' . _ (Certainly most of us have ran-into old Harley-types
who scoff at those who refer to any non-Harley as a 'bike' .)


" I've had many brands through the course of my forty years of motorcycling and have referred to them all as 'bikes'. "

____ Well that view-point sure does seem to make/back-up my exact-point for me ! ...
THEY were all indeed mere bikes, while any Duc-single within that collection should not be considered to be just one of the same, but rather, a 'DUKE',, that is to say, at least for those of us who notice and really care about THE difference.


" So I don't think that I shouldn't be lumped into a 'newby' category as regards Ducati motorcycles. "

____ First off here, it's quite clear to me that my wording did not intend for you yourself to be thought of as any kind of "newby" at all ! _ And besides that, I had mentioned that my rant really had nothing to do with any post within this thread, and thus you should not have jumped-to-conclusion that I may have been referring to yourself any at all, directly or even indirectly !
__ A 'new-boy' is not a newby/newbie, anyway ! ... Whenever I state "new-boy", I'm referring to those of us who are at least a generation out of sink with those of us who were old enough to be able to ride DUKEs back when they were still being NEWly sold on the market,, that's pretty-much all there is to that.
From that which you say about yourself, it's fairly clear that you're not a new-boy amongst the rest of us, and probably (like most others), just use the term 'bike' due to peer-pressure within the area you live in and what everyone-else says.
But it's still notable that the new-boys of us here, way over-use the term 'bike' ! _ (As I'm sure any old Harley-man would much agree.)
And I therefore tend to over-use the name 'DUKE', so as to help compensate for that, (in a seemingly lame-attempt to bring a more normal/in-line balance to this w.site).


" The older I get, the more I've become aware of the fact that Ducatis are not the only motorcycles on the planet although I still regard them as one of the best. "

____ Let's not kid ourselves, our old DUKEs are no-where anywhere near being one of the best of motorcycles ! - (Except perhaps, before 1968.) _ And all level-minded motorcyclists/bikers no doubt wonder what-the-heck us Dukers are so intent on, concerning Duc-singles.
But there are others here besides myself who at least have a grasp of the true-lure that the old DUKEs certainly have for those with the perception to realize it ! _ And we know who we are and we FEEL that unique-mystic that only the OHC-DucSingles -(DUKEs) possess, and we really LIKE-IT !!
I suppose that the wives of any of us who are loosing that FEELing of ours, are sort-of becoming relieved that their husbands seem to be getting cured of our common-desire. _ But I myself really don't want to loose mine ! _ The wife can go first, (as far as I'm concerned) !


" They are just not sacred anymore. "

____ That statement makes me think that you've lost it.


" I don't doubt that the white cam would provide an improved lower end performance. "

____ That's not only very quite true but it also doesn't give-up any notable loss to the wilder cams, for normal street-legal/muffler-equipped 350s !


" But since the bike is no longer a Scrambler but has evolved into a 'Roadster', perhaps the green/white cam may be more suitable. "

____ If I didn't seem to agree with that conclusion before, let me now make it clear that the particular G&W-cam which you now want is EXACTLY the cam for you & your DUKE ("Roadster"), as it is in the process to become !
I had never meant to suggest that you were in pursuit of the wrong cam for your particular project, only that the almighty G&W-cam is not all what it's been cracked-up-to-be.


DUKE-Cheers,
-Bob