Engine : Rebuild : Top end

The barrels have arrive from PJME with some nice new pistons.
Good Job.
Ports nicely chamfered in.
Everything went together nicely with no drama.

Next up… the reed cages and rubbers. this is all of the crap from the “parts box” accumulated over 30 years.
The YPVS and TZ cages and rubbers modded for 34mm carbs can go back in the box… I am going for a standard build here, and in any case, they won’t fit the unmodified barrels.
Ditto, the cages which have been filed out, again, standard build required.
I found a pair of unmodified cages, and some original reeds which I selected to do the job. they will need a bit of a clean up!
The rubbers are a little cracked, but not all the way through, and the area around the balance pipe fittings is sound on both.

Added the cylinder head reed blocks and carbs, then set the static timing.

I had marked the stator when I took it off by scribing a line on it where the case joins.
After finding TDC using a dial gauge, and backing off 2mm, (as per the Haynes manual), I found that the engine had been timed at 1mm BTDC by the previous owner. Deliberate? who knows.
I scribed a new line on the stator at 2mm BTDC and tightened it all up.

I added the carbs because I wanted to
a) Cut a piece of petrol pipe to the correct length to join the carbs.
b) Check the length of the oil feed lines.

Curiously, the oil lines which I had taken from various old oil pumps from the parts box, were the wrong lengths.
The shorter one for the RHS carb was about 3cm too short, and the longer one for the LHS carb, when routed under the carbs was circa 20cm too long.
I took the precaution of ordering a length of oil line/fuel overflow pipe from Norbo at RDLCCrazy, so I’ll cut that to length. It has the added advantage of being transparent, so I can see the oil flowing through when bleeding the oil pump.

There’s nothing left to do now but put the engine in the bike! Another milestone of sorts.

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