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XR500 HPF C&J monoshock

The 4 stroke unicorn of the early 80's

XR500 C&J HPF monoshock 1.jpg

For me this is the Holly Grail. I am told only 14 (or is it 28?) were built in the early 80's but there is some controversy about this with possibly copies being made, originals being transformed and re-transformed, exported to the UK, re-imported to the US etc. I know of 2 that have been converted to twin shock (a shame in my view since twin shock C&J frames are still available).

This one comes directly from its birth area, Southern California where I bought it in December 2011. I am now the third owner since December 2011.

The previous owner told me that Don Vesco put his fingers in it back the day. The cylinder shows the remnants of a "Mugen" sticker.

It even has a California title!

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Some time in 1980/81 (?), being built.Note the Fox Factory Forx. Why the black rocker cover?

For sale, Dec 2011. Looking suitably tired. The Fox Factory Forx is gone but the main bits are there.

Delivered by its former owner (Bruce on the left), back to its creator, Jeff Cole on Dec 31, for some minor frame repairs.

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I never liked the 79 CR250R seat. It looks antiquated and leaves a goofy hole near the fuel tank. So I experimented with a 1983 CR125 seat base. After some adjustments, it went pretty well.

The original 44mm Fox Forx had been replaced with a later Honda disc brake fork before I bought it. Thankfully, there was a Fox Forx lying around in a box (as they do...).

The Fox Forx is now on after getting an aluminum steering stem turned and pressed in. It is just perfect.

Rim is 1.85" Sun from 1982 that was also waiting patiently in a box. Spokes are new Bucchanan's.

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The Fox scutcheon was an almost perfect immediate fit for the Honda 1983 CR480R back plate and hub. The cable bracket on the back plate was snapped (as very often on these CR480R). JP Morgen in San Francisco did a great fix with a screwed in aluminum bracket. Perfect.

I had a timid shot at building an airbox (missing when I bought the bike).

A couple of kind folks have offered me a period or newly built box, but I am still considering the options.

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When I bought it, the suspension looked tired, slumped, a bit like a Dachshund. Much better now.

And in this configuration I finally have found a bike that is right for my size! I am 6'4".

Tackling the "pièce de résistance", the rear suspension.

It is all rather well made, with the only issues being a broken top roller bearing on the crank lever and bolt pins worn all around.

Shock and spring were set-up by the famous Phil Douglas. What a treat!

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