Damn this bike still isn’t ready! Almost there just the exhaust, oil cooler, carb bellows and oil and we should be away.
Where did all the time go? Well first off I spent time grinding the shims some more. Settled on .15mm inlet and.20mm exhaust and got to this fairly quickly by holding the shims against a grinding wheel and then finishing on a wet stone. Time leaked away when I tried to get the cams to move smoothly.
The cam bearings are held in place by pillars that have a metal brace over them – these need to be fitted into ‘flats’ on the bearing or as you can see the ends of the bearing get mangled – no I didn’t do this someone in the past has…but I had to tidy it up with light emery. Eventually the cams ran okay but by then time was moving on.
Next hassle was joining the cam chain. First off the cam chain had become trapped between the front of the head and the frame. All bar the top rear engine mounts had to come out to cant the motor back and up to dislodge the chain. Next up the cam chain has to pass between a narrow gap beneath a bearing retainer. Using the LED light off the bike as a torch I eventually I found that the way to thread the cam is in through the back of the barrels with the cam chain adjust removed. The chain then drops onto the crank sprocket and can be fed down and out the bottom of the engine. Hook the end of the cam chain to some lock wire and thread it back up the front of the motor – oh yes with the cams removed…which you then have to check spin smoothly. If you just drop the cam chain down from the top then it goes the wrong side of the bearing retainer and seems to be a link too short (it isn’t).
Of course once this has been done the next pain in the arse is getting the wire back through the cam chain link. I reused the old wire as I couldn’t find my spare – lots of swearing and help from Mrs A.
I think decided to put in the cam chain adjuster blade – had to remove an HT coil for access and even then had to tap the blade past the top rail.
Progress was swift once the top end was built but became frustrating as I realised things had to go in a particular order. I remembered that the cover over the starter motor can only be removed with the cam chain adjuster bolt removed – that’s what I thought but found that with the cover on I couldn’t get the cam chain adjuster in to the rear of the cylinder so off with the bloody cover and start again.
It made me think that maybe you would be better off building the entire motor on the bench and once done hoist it in…next time huh!
Still almost across the line and with the reconditioned head, fresh rings, smooth cams and new allen bolts this is going to be maybe my best Atlas yet…