The new TR1 engine - fixing some older faults and headwork (part 25)

Sometimes you have to accept defeat and start moving on. The whole cylinder fixture was a nice idea, but it just shifts around too much. I have an idea, that I will give a try on the wrecked cylinder, but for now I want to crack on and finally reap the rewards of more than a year's work.

As you can see, I painted the bottom of the cylinder and took a very light cut (0.05mm) and it just wouldn't work. If you increased the RPM on the lathe whole lot would start to oscillate and twist itself into a pretzel.

Time to get back to work on the engine itself. I installed the lower camchain sprockets the wrong way round, i.e. front sprocket on the rear and rear sprocket on the front cylinder.

An M6 bolt, will make the perfect plug for keeping the sprockets under tension and this makes installation tons easier.

If you mark the two teeth adjacent to the "peek-hole" on the rotor with some paint and the single tooth that should go between them on the sprocket, it's totally doable to install the camshaft sprocket without removing the rotor. (Getting the pin out is impossible without turning the crank though.)

And for future reference: the front cylinder, which has its primary gear on the RIGHT is marked "R".

If you followed this blog for more than 5 minutes, you might have worked out, that I am not one massively into shiny paint and polished metal. It's an entirely different story, when valves are involved.

In order to achieve this finish (and lighten the inlet valves in the process), I put some old fuel hose over the valve stem and clamped each valve in my lathe and then went through 120, 220, 400 and 800 grit sandpaper always making sure that none of that touch the actual mating surface of valve and valve seat.

As you can probably make out in this picture, the inner valve springs are the softer Virago 1100 kind. They are being swapped in as the stock blue springs are way too heavy and actually overstrain the valve train and cause premature rocker and cam-failure.

If you have a rather limited understanding of port-work, it's best if you only touch up on obvious mistakes, i.e. casting flaws and ridges and steps in the ports. As these are going on an everyday engine and the overall port design is actually pretty sound, there's only very little that absolutely HAS TO BE touched in those larger ports.

As a matter of fact the only real area of concern I found on these was a step, where the original casting had been undercut to fit the valve seats and a few casting flashes on the inlet port sidewalls. Both were maybe 30 minutes work (per head) with a small flapping disk on a rotary tool.

In this picture you can see where I blended the seat into the port. Also notice the stock exhaust valve in the picture. 

And shiny bits installed. 

Next up: a frame and fork swap for unbent items (did you know forklegs don't usually jam in yokes - weird I tell thee...) and painting the cylinder heads silver.