Curtis Racing Frames

Here is a picture of a completed Seeley Norton Replica started in 1972. It was about this time that I started making plans to set up a business manufacturing racing frames for all types of competition motorcycles.

Curtis Seeley Norton Replica

From 1973 – 1977 I operated a company called Curtis Manufacturing and Service Ltd. Based in Richmond, B.C. During that time I found there was little demand for Seeley 4-stroke frames. However, one of my employees, Lief Sorenson, wanted to build such a bike, and here you see the finished product – it was raced by Leif and ended up in the hands of Peter Gagan, founder of Canadian Vintage Motorcycle Group (CVMG), who sent me this photo in the late 80's. Thanks Peter.

The frame featured chrome moly 4130 aircraft tubing of 1” diameter, bronze-welded together just like the Europeans and Brits were doing with their frames. It differs from a real Seeley because Seeley used a larger diameter, round tubing for the swing arm where I used box section rectangular tubing.

The bike featured Betor front forks, Kawasaki brakes and Boyer transistorized ignition. It also had one of my first attempts at an aluminum gas tank. The Dunstall fairing and front fender, and the Hansen style seat were all products made by Curtis Manufacturing in Richmond B.C.

This bike was completed by Leif in 1973. The caption refers to the year of the engine.

Curtis Racing Frames started out by producing road racing frame kits then quickly added dirt track frame kits, which became the main demand item. Dirt Track or Flat Tracking was very popular at that time throughout Canada and the USA. We built some drag racing, moto-cross, and street frame kits, and also complete bikes.

Because of my close working relationship with Deeley Yamaha Racing department, I came into contact with Champion racing frames owner Doug Schwerma of Hayward California. This series of pictures shows an XL Honda single four-stroke in one of our race chassis. It looks like a Champion racing frame and in fact most of the geometry follows Champion's ideas of the time. But I always felt the frames sat too high for what they were designed to do, so I lowered the engine centre-line 1.5” to 2” depending on the engine, and they handled very well.

Worthy of note here: This bike features Curtis Racing fibreglass, Betor/Mulholland front forks, Honda XL350 single SOHC engine bored out to 412 cc. with Powroll racing parts and Mikuni carburetor. We used K and N air filters, Barnes wheels, Airhart rear brake assemblies, Boge rear shocks and Goodyear and Pirelli tires.

Note: these chassis were made from chrome moly 4130 aircraft tubing TIG welded. Our US racing customers preferred TIG welding over bronze welding, so we changed exclusively to TIG welding.

Next: Flat-Track

If you have any information or pictures of Curtis Racing Frames from the period please Contact Us. We would really like to feature as many frames and frame modifications from that period as we can here.

Curtis Racing Frames; a sticker from 1970's

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