The rear suspension

Unique suspension of the HPF C&J monoshock chassis

Checking the swingarm with a magnifying glass, I found no less than 11 micro-fractures. These were beautifully weld-fixed by a specialist shop. The main pivot bushes were of course replaced.

Microfracture on the swingarm

When I got the bike, it looked quite tired at the back. It turned out that the custom made suspension mechanism was tired: all the bearings and pins were shot, and the funky suspension lever was stretched.

Broken needle bearing

I decided to toss the needle bearings that I found in there and replace them with solid steel bush bearings. What is needed for these pivots is strength and endurance, not rotation speed.

Old and new suspension levers

It took me a while to find the proper hardware from McMaster Carr.

All new parts for the suspension crank.

The Fox TwinClicker was due for a service. I got all the service parts for the Fox TwinClicker from Thor Lawson of course, and sent the little clicker wheels to be reanodized. 

Looking all new almost complete

Servicing the shock was a pleasurable experience, but... back on the track, the rear of the bike was as stiff as a log, pretty much impossible to ride.

All new bits for the suspension.

One year went by.... the bike stayed in the garage (for multiple reasons)

I was saved by meeting Phil Douglas of Aftershocks Suspension a real pro and artist of suspension (and also veteran silver medallist of the ISDE!!)

Shock on the dyno, hooked to the computer.

In a couple of hours at his shop, Phil put the shock on his dyno, connected to his computer, established that there was too much of this and not enough of that, replaced the spring with a lower rated one (8.5 kg/m vs. 10.4 kg/m), removed some of the valve shims inside, educated me thoroughly on the inner working of a shock absorber, et .... voilà, tuned for middle range on 14 out rebound and 4 compression.

The before and after readings. Near perfect curve after tuning.

I cant wait to have Phil work his magic on the Factory Forx with the emulators...
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