Hi guys
an update of the work in progress
I had a pair of hagon rear shocks that were usable but the springs were rusty.
So I decided to take them apart, remove the rust and the old paint and to respray them.
It turned out to be quite good and they were ready to be reassembled.
The ones I have turned out to be really easy to reassemble.
- the hagon rear shocks
as you can see I use tools that are used in the car garage business to compress car springs, they're just a bit adapted, the hooks are smaller in order to fit over the bike springs.
- the spring compressors on
When the springs are compressed you just slide the two half moons between the spring and the head of the shockabsorber and release the springcompressor.
- one done, one to go
Just keep in mind to be carefull, when one of the compressors jumps out of place and your fingers are between the spring and the head of the shock it will certainly be very painfull!
As you can see they look allright.
- the mounted shockabsorber
Once this was done I sprayed the cilinderhead with heat resistant paint.
I use an old camshaftcover and some old rubber caps to cover the upper side of the cilinderhead.
The exhaust ports and the rev counter hole are filled up with paper.
I allso mount old spark plugs to prevent paint coming in the spark plug holes.
The underside and the intake ports of the cilinderhead are covered with tape.
- the tape covered underside
- the newly sprayed cilinderhead
After a few days the paint cured and it was time to polish the fins.
I use a simple electric tool to remove the paint, the abrasive paper does the job, I start with a 120 grain and end with a 320 grain paper
- the fins before
- the polished fins
After that it was time to reinstall the valves.
The valve seats and valves were allready lapped and kept in a box so I don't mix them up.
- the box with the valves
Keep in mind that when you have an empty cilinderhead you start with putting the valve spring seats in first, then you put the oil seals on the stem guide. I use viton oil seals, I was told they last longer...
After that you put in the valve, the two springs and the spring retainer. I allways use a tiny bit of high temperature grease to put on the valve stems
- the high temperature grease
Compress the valve springs and put the slit keeper on the valve stem.
Don't mix Z900 valves with Z1000 split keepers, they're different.
After the valves are installed, I put the buckets with a small shim on the valves, install the camshaft and I shim them up, one at a time. Before putting the shims in, I measure them and I write the thickness down on a piece of paper. It's easier to determine the correct thickness of the shims to obtain the correct amount of play afterwards.
Do one set of valves at a time, don't install the two camshafts at the same time, when turning the camshafts, the valves could stick behind eachother.
And for those who have a shop manual: DON'T tighten up the bolts of the camshaft caps to 1.7 Kg/m of torque as mentioned in there. The maximum torque is 1.2 Kg/m!
You see, even in Japan mistakes are made when publishing a shop repair manual.
That's all for this week.
See you next time.
Philippe