Camshaft advice

[veloduke]

Hi

I'm assembling a 450 from a mix of parts (all 450) and I was looking at the camshaft. No markings or paint on it. All the engine parts came from the US I believe.

After (doh!) I had the cam refurbished I realised that this might be quite radical in its profile.

IMG_0486.jpg

IMG_0485.jpg

Is this going to be unsuitable for a road bike?
It also has solid rockers, which I'm assuming means changing shims to adjust the clearances.
The cylinder head came in one lump already assembled with these parts.

I apologise for my lack of knowledge, I'm still on the (expensive) learning curve.

[ranton_rambler]

I’m far from expert but have found a load of cam data on a website. Will find a link later when I’m at my PC.
A simple thing to do first is to measure the lift.
Ian

[veloduke]

This thing has 10mm approx. lift inlet and exhaust (!).

Phil Joy said he thought it was an aftermarket cam, and in Jim's cam data, Syd's is mentioned, referring to a cam with 10mm lift in and ex.

Too extreme for a road bike?

[graeme]

Looks to have lots of opening duration
Should be ok for a 450 that needs extra time to fill the cylinder.
10mm lift isn’t that much.
Eldert, Nigel or Ducwiz will know more.

Graeme

[Eldert]

Hi Max

looks like a race camshaft to me . what diameter is the base circle ?

in order to fit a high lift camshaft into the cylinderhead the tunnel has to spindelt out .

did someone do this to your head ?

the only way so find out what camshaft you have is to put a degree wheel on the engine and take readings .

i use smal springs i put in instead of the heavy hairpin valve springs to make taking readings easyer .

Eldert

[veloduke]

Elders

The base circle diameter is about 19.9mm. The cam has been cleaned up so this could be different from new, although not by much. There wasn’t much scoring before I sent it away.
Can’t see any machining done to the head, the cam goes in ok.
Unfortunately I have no history for the head.
I believe the engine parts came from someone in the USA who used to race bikes.
I am not going racing, so am concerned that the cam may be unsuitable.

[ducwiz]

I agree with Eldert - unless you do not record the timing curves you may not identify the camshaft.
I linked "Jim's cam data" for reference https://www.dropbox.com/s/hhqkk3ubpqo2v1q/JimsCamData.pdf?dl=0. The list contains no camshafts with 19.9mm base circle diameter.

cheers Hans

[themoudie]

Aye Max,

I'll no comment on your cam, you have Phil Joy and Eldert offering advice and guidance. Phil Joy certainly has long experience with Duke single cams and associated rockers and Eldert knows his Dukes.

As for your query "It also has solid rockers, which I'm assuming means changing shims to adjust the clearances."? The answer is yes, you will need shims. Personally, I would stick with shims, rather than looking for the alternative screw adjusting, lock nut, pivoting type of rocker. On my '74 450 MKIII head once shimmed, they have rarely require adjustment in the 44 years of ownership and with over 75,000 miles under the wheels.

Good health, Bill

[veloduke]

Thanks Bill

I was not really trying to find out what cam it is, but if the general profile gave some clue as to whether or not it would be suitable for a road bike.

Whatever, I have decided that it's going in, and I'll find out when I try to start/ride the bike .

If it's unsuitable, it's not a great job to change it.

[Eldert]

Hi Max

this being a aftermarket camshaft putting everything on the timing dots very seldom works .

to make the most of this camshaft you have to put a degree wheel on and take timing figures and adjust the timing if needed .

Eldert