Green White Cam

[Bevel bob]

Sorry ,late reply, log in problems. My GW? cam has a bse circle 0.893 and O/A 1.244 in 1.226EX. Its up and running now but i did not get chance to check timing. Lift 8.915in 8.458 ex in mm. Started 2nd kick after a good kickback. last time i checked the valve timing it looked more like the GW figures than any other.

[DewCatTea-Bob]

" My GW? cam has a bse circle 0.893 and O/A 1.244 in 1.226EX.
Lift 8.915in 8.458 ex in mm. "

____ I've checked your results of your cam-readings, and it seems that you've correctly done all the math !
__ So if your cam shows no signs of abnormal-wear, (I much doubt it does), then your cam is not only NOT a G&W-cam, it's actually a 'Mach1-cam' ! _ Because with those particular lifts (of 9mm-intake & 8.5mm-exhaust), it can be no other DUKE-cam !! _ As the M1-cam is the ONLY Ducati-camshaft with that particular set of lift-figures !
__ You should be happy to find-out this info ! _ As (in my opinion), that 'Grey-cam' is the most desirable DUKE-cam that Ducat ever made !
Why did you ever believe that your DUKE had a G&W-cam, anyhow?
__ The G&W-cam (as well as all wide-case cams), has a Base-Circle that's ground-down almost even with the shaft-diameter itself ! _ While the M1-cam has a noticeably larger base-circle, (compared to the standard-size shaft-diameter of the camshaft).
So did you happen to notice whether or not your cam's base-circle was nearly flush with the shaft of the camshaft?
____ Also, you now have good reason to be concerned about what-ever your chosen valve-clearances are !
What did you set them at?


DUKE-Cheers,
-Bob

[Jon Pegler]

RE; orange and white cam.

The base cicle on my orange and white cams is 22.95mm.
Inlet lobe lift 9.05mm
Exhaust lobe lift 8.50mm
Whilst the actual lift is similar to quite a few other cams, the duration is considerably longer. One of Elderts graphs shows this.
The base circle is far from flush with the main body of the cam, as you mention with the green & white cam
.
I'm not certain but I think some of the Spanish heads had an enlarged camshaft tunnel machined into the head casting to accomodate the relatively large camshaft.It's only a couple of millimetres larger as I remember, although I'm not entirely sure. I'll have to dig out an Italian head to compare the size with a Spanish one.
The late Spanish singles also came with double coil valve springs. These are a sure way to destroy any camshaft and rockers fitted. Better to return to hairpin springs unless you like stripping your head down every 2000 miles.

Jon

[Bevel bob]

Thats good news!, clearances are set at 6 and 8 thou, the cam was only visually I D'd by another DUC nut who usually has a dozen or so bikes .Next time I set up the disc i'll get some figures.The previous owner also said it was a GW cam,.. The bike does not seem to have the mid range flat spot that the GW is reputed to create so maybee------ I do have a hesitation after being on the overrun, ---29d dellorto.

[DewCatTea-Bob]

" clearances are set at 6 and 8 thou, "

____ Your exhaust-clearance may be set a bit tight, as the factory-recommended RUNNING-clearances for the M1-cam are .006" for the intake & .012" for the exhaust ! _ (Although I think it's safe to go a couple-thou tighter.)


" Next time I set up the disc i'll get some figures. "

____ The preset clearances for checking the valve-timing of the Grey/M1-cam are required to be .010" for the intake & .016" for the exhaust ! _ Those clearances are needed to be set .004" greater than the running-clearances, so as to avoid getting your timing-readings contaminated by the clearance-ramps of the cam-lobe ramp.


" The previous owner also said it was a GW cam,.. "

____ If it was actually a real G&W cam (without obvious wear), then you would've measured it's intake-lobe to be a whole mm taller !


DUCATIly,
-Bob

[DewCatTea-Bob]

By: Jon...
RE; orange and white cam.

" The base cicle on my orange and white cams is 22.95mm.
Inlet lobe lift 9.05mm
Exhaust lobe lift 8.50mm
The base circle is far from flush with the main body of the cam, "

____ I-don't-know, Jon,, normally, I'd quickly identify a DUKE-cam with those lift-figures as being the 'Grey-cam' !
And while I really don't know what all Mototrans has been up-to, I'm quite positive that if an Orange&White racing-cam came direct from the Ducati-factory in Italy, it would certainly then have some really impressive lift-figures ! _ Such as 12.5mm for the intake & 11mm for the exhaust, for instance.
__ I'm now much suspecting that you may have a counterfeit O&W-camshaft ! _ Where did you get it? _ And can you really TRUST the source for that cam of yours?
As I've heard tale of some really bad counterfeit racing-cams causing really sheotty running, much like you've described for yours !
Sorry to say !


" I'm not certain but I think some of the Spanish heads had an enlarged camshaft tunnel machined into the head casting to accomodate the relatively large camshaft.It's only a couple of millimetres larger as I remember, "

____ I can't confirm that but, I have heard of such before from some-where. _ It would indeed be interesting to know for sure !


" The late Spanish singles also came with double coil valve springs. "

____ I was unaware of that ! _ It would be very nice to see some pix of that set-up !


____ Hopefully, Eldert can confirm details concerning all the issues brought-up within this post !


Hopeful-Cheers,
-Bob

[Jon Pegler]

Orange and white cam.

The cams I've got have all come out of Mototrans engines. Most have done a very low mileage but show a small amount of wear. They still have the orange and white markings on them so I don't doubt what they are. They are certainly different from grey cams and green and white cams, with the valves open for much longer. Actual lift is dependant on a number of factors including piston and combustion chamber design. Duration can be more important. The Ducati singles never had the best combustion chamber shape to start with, so if the lift is limited due to the proximity of the piston to the valve head, duration of the valve opening periods is the way to go to increase flow.

The double coil springs in the late Mototrans bikes used the outer spring from the 750/860 and the inner spring from the 350/500 GTL or GTV, but used a different top and bottom spring retainer to the V-twins. Fitting hairpin springs only entails fitting the two small roll pins into the head to locate the hairpin spring retainer. The heads already have the holes drilled either side of the valve guides.

[DewCatTea-Bob]

" Orange and white cam.
The cams I've got have all come out of Mototrans engines.
They still have the orange and white markings on them so I don't doubt what they are. "

____ I've never had my hands on one of those cams, so I can't say much of anything about them !
I'd suspect that they were made (exactly as you seem to believe) they way they are by Mototrans themselves, and not actually as Ducati might have done. _ But I really can't say, and so I sure hope that Eldert can shed some light on just what all the specs are actually supposed to be for the (original Italian) Orange&White camshaft ! _ (Perhaps there's also a DESMO O&W cam, adding to the confusion?)


" Actual lift is dependant on a number of factors including piston and combustion chamber design. "

____ Well Jon, perhaps you didn't choose your words very well so as to express exactly what you actually may have meant to state here...
Because the only two factors which actually determine the 'ACTUAL-LIFT' at the valve-head from it's seat, is the peak-height of the cam-lobe in combo with the 'Rocker-Ratio' !
And for DUKE OHC-singles, that ratio is 1:1.04, so the actual-lift is actually just 4% greater than the cam-lobe's max-height ! _ Nothing more & nothing less than that amount, and nothing else matters concerning that !
__ The only concerns about 'lift' as you've brought-up, are that it's not left to be too high during 'overlap' TDC, which is usually never a real concern, (as the valve-pockets in the top of the piston can always be further deepened).

____ (With top DUKE-men such as Eldert watching-over what I state within my posts here, I have to be fairly confident that what-ever I state, is indeed actual fact ! _ At least I hope, [& expect] that Eldert will always correct or at least question any questionable-statements which I make .)


DUCATIly,
-Bob

[Eldert]

pictures of the late Mototrans coil spring setup coming up







the cilinderheads i have do not have the holes in it for the rolled pins that secure the hairpin spring holderplate

Eldert

[DewCatTea-Bob]

" pictures of the late Mototrans coil spring setup coming up "

____ Eldert, I was really hoping that you'd have some comments about some of the other things that were brought-up, as well !
Such as if the Mototrans cyl.heads which are stock with those coil-springs, have a larger camshaft-tunnel where the shaft's bearing-support/cover fits (snugly?) into.
__ And I was also hoping that you could tell us what the lift-height is of the cam-lobes on YOUR Orange&White camshaft !? _ (As I can't believe that the 'Megacycle 564 00' would have a lift of only 9mm!)


Thanks,
-Bob