Timing and rebuilding Skootamota engine.

Hi.
I’m in a position to start rebuilding the box of engine bits I have for my bike.
The engine had already been taken apart. The single tappet and rocker were seized.
Does any one have information regarding setting up the timing for the tappets in relationships to TDC?

I am missing the drive sprocket for the magneto so I can’t set that up yet!

Has anyone got photos of the engine with the fly wheel removed as I am missing the plug that covers the magneto drive sprocket and the nut/ cover of the main bearing cover? I’m not to sure what covers the external bearing set in the brass casing as all posted photos show the fly wheel in place.

I need help!

Cheers Neil. 07718146938.

Hope this helps with the pictures, let me know if you need anymore

As I remember, on Giovanni's engine rebuild the inlet & exhaust cams were engaged to be equal about TDC. The assumption being the inlet and exhaust overlap are equal, which worked for Giovanni's engine.You also need to be careful about the adjustment of the pushrod and tappet so that the relative angle of the two parts ensures the pushrod clears the barrel throughout its travel. We timed the mag (which has no adv/retard) at 35deg BTC. This seemed to work; however playing around with the timing may well find a better balance to ease of starting and full speed running. I will look out if we have any photos taken during the build. There is also an operational Skootamota at Brooklands where I can take some assembled engine pictures if needed,
regards
Ian

Hi thanks for the pictures.

The external crank shaft bearing , looks as if there are rings covering the bearing???

How are the rings/ plate held in position? Is this detail original or an engineered solution to keep the bearing clean and dry?

Regards Neil.

I also noticefrom thebpicturs that the brass cover plate does not have a small inspection access port for taking off the magneto drive sprocket to enable the magneto to be removed without taking the main cover off???

Is that detail evolution or didn’t the early engines not have this ?

Think its just a metal shielded bearing, if i am looking at the right part. The inspection for the magneto came for later engines as far as i know, well the later engine we have has one, this one doesn't, not the engine on the running Skootamota, it was a right faff changing the mag!