Cam sprocket Megacycle cam

[Hudriwudri]

I have two short questions,

Considering that there are two camshaft sprocket types is it possible to change the sprocket type from one cam to the other?
If so how much press force is needed? Doable on a small toolroom lathe, as I have no Shop press.
I unfortunately have currently no xs cam at home to have a closer in depth look, but would need to know as I might need to buy a used cam as a core to send it in to Megacycle.
I have a spare 880 engine that should be a later type european engine, but for personal reasons (family, porting jobs for friends and race colleagues etc etc) i currently don't want to open it to investigate to avoid the dreaded pandora's box phenomena else known as parts laying around still life.

Anyways thanks for your kind Info and second question:

In case one of you would have a good Megacycle 250-30 or even better a -40 for sale i would be very interested.

All the best and to everybody a hopefully happy and healthy new year.

Christian

 

[650Skull]

if you change a 447 Type, (74-84), engine cam sprocket to a 256 type, (70-73), or vice versa, then the sprocket at the crank has to be changed as well to match the cam sprocket. Come as a set.

 

[Hudriwudri]

Thanks
For the info!
I investigated yesterday a little bit, and was afterwards under the impression that the cam sprocket could be pressed off of the camshaft.
Is that not the case?
Other question, i highly assume one can pull off the rockerbox and count the teeth without risking that the chain slips?
Eventually I will take the head off anyways but at this point I do not want to open another barrel that might cause me delays or missing parts.

Thanks and kind regards
Christian

Edit: great info there, just found out sprocket can be slipped of:
http://www.xs650.com/threads/camshaft-sprocket-swap.29831/

 

[stinky78]

hi Christian, they can be pressed off, haven’t done it myself but numerous members here have posted about doing it, I think you’d struggle to do it without a press though.

 

[Hudriwudri]

Dear stinky,

First of all, happy new year to you and your dear ones and all the best for the coming year.

Im most likely gonna press it off with some heat on the lathe and if it comes hard to hard with some brass pieces and a lil hammer in-between lathe centers.
Now I just have to figure out if I take the -30 or the -40.

Anybody know maybe their overlap lifts?

The slotted sprocket and adaptor i most likely make myself on the lathe and mill as a way to save some money during these frugal covid days.


Kind regards
Christian

 

[Ratranger]

The sprocket will press off without a big problem. Getting it back on and oriented right takes a try or 2. Best way is to heat it until it slips on. Then install the cam and check how far out you are, mark it accurately and remove, heat and align the marks you made, then recheck to make sure you did it right. I've got a 256 cam in a 447 rephase.

 

[Hudriwudri]

Hi folks,

Thanks for the kind answers and help.
Regarding my decision on cam profile i will try in the next coming days to put some spare head with valves together and try to measure safety margin between valves on overlap as well as Imho almost more important kinematic rocker angles and see how it goes with pressure angles on the valve shafts, cuz as mentioned I would love the idea of some cam in the range of 0,5ish valve lift and reasonably short duration in order to open the barn door as much as possibly through the period of "let's call it" highest pseudo static demand.
Given that the tt500 rockers are a whole lot shorter I have a hard time to think that the wear out would be prohibitively high on guides and shafts with 0,48.
(Considering that I run 0,58 lift in my sr500)

Kind regards and thanks again
Christian