Stainless Denco replicas for the Kawasaki H1

I needed chambers for a Kawasaki triple that I was restoring and decided to make my own after being disappointed with what was available for these bikes. The goal was to make exact copies of vintage Denco chambers to ensure good performance and stick with the period look.

A  few modern twists (improvements) were added to my reproduction Dencos though…

1) The pipes, manifolds, and mounting tabs were constructed from stainless steel so they could be polished to look like chrome and would never rust.

2) The manifolds were machined for a tighter fit on the head pipes then the original Dencos to prevent oil from constantly drooling down the front of the bike.

3) They would be fitted with adjustable-removable mounting brackets to make fit up on these old and slightly unique (from age) bikes easier.

First careful measurements are made from authentic Kawasaki H1 Dencos to make paper models and CAD files for precision laser cut stainless steel cone sections.

modeling daves pipes copy

Next more prototype parts are designed and fabricated including nice CNC mandrel bent head pipes. This produces head pipes of constant diameter with good resonate properties, not cheap draw bends that leave the pipe out of round!

working up parts copy

The manifolds are machined from quality 316 stainless steel for good high temperature corrosion resistance. All welding is done by hand using a “back purged” GTAW process to produce strong, nice looking welds, with good corrosion resistance.

Machining and Welding Manifolds copy

With manifolds and belly sections in hand the prototypes are fit up to a bike! fitting up Denco replicas copy

Satisfied with the fit of the prototypes it was now time to work up a bunch of parts seeing that my friends would want some of these pipes as well for their Kawasaki Triples…

working up parts 2 copy

At this point it is just welding, welding, and more welding! Each set of pipes has over 25 linear feet of seamless weld bead… Welding Denco Replicas copy

Then the baffles are installed (with glass packing), and the pipes are polished. Bafflels and polishing copy

Pipes on bikes!

H1 Denco Page Header

1970 H1

1970 h1 stainless denco

1972 H1

1972 Kawasaki H1 with Highwayman Denco Replicas

1976 KH500

1976 Kawasaki KH500 with stainless dencos

1976 kawasaki KH500 with stainless dencos 2

Rare factory grey 1969 H1 in America

Grey 1969 H1 with Highwayman Denco Replicas

Rare factory grey 1969 H1 in Japan


Late model H1 and KH500

Late model Kawasaki H1 500 and KH500 with Stainless Dencos

1972 H1B (a work in progress!)

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