Hi fellow bikers,
When I say CB450 Racer, I do mean racer:
I used to campaign this in the Belgian Classic Motorcycle Racing Championship until a crash in Chimay put me off racing. No major damage was done to me or the bike, but I didn't want to take the risks anymore.
Anyway, the bike was dismantled and boxed up for a few years. About a year ago, I had figured out that it was going to be changed into a hardtail bobber, with a racing twist.
Put the frame in a jig with the rear swingarm to locate the rear axle plates, cut-off the rear section bit-by-bit to be replaced by 25mm x 2.5mm seamless steel tubing. Before anyone wants to comment, I know the headstock should be held in the front of the jig. As Mr. Sinatra said: "I did it my way", checked the trueness of the frame and welded the downtube and bottom rails to the jig. Trueness was checked throughout the building and welding of the frame.
As I am not a professional welder, I only tacked the tubes together. This was then TIG-welded professionaly by a friend.
The simplicity of the design showed when it came out of the jig.
Time to get it back on its wheels, so a pair of old CB450 wheels were fitted.
The frame needed more strengthening, so two tubes in front of the rear wheel (top ans bottom) were put in:
A mock-up engine went in and it was time to see where the seat was going to go. Note the position of the original footrest... Way too high!
So the footrests were lowered, the sidestand shortened, the rear brake-mechanism was build (from some CB500Four and CB350K4 parts I found), the rear fender (aka original front fender) was tweaked to closely follow the radius of the tire and fitted.
Time to go back to the welder and get it all welded up professionally. First the top:
... and then the bottom:
A lot more work has been done since, updates will follow shortly. Enjoy!
When I say CB450 Racer, I do mean racer:
I used to campaign this in the Belgian Classic Motorcycle Racing Championship until a crash in Chimay put me off racing. No major damage was done to me or the bike, but I didn't want to take the risks anymore.
Anyway, the bike was dismantled and boxed up for a few years. About a year ago, I had figured out that it was going to be changed into a hardtail bobber, with a racing twist.
Put the frame in a jig with the rear swingarm to locate the rear axle plates, cut-off the rear section bit-by-bit to be replaced by 25mm x 2.5mm seamless steel tubing. Before anyone wants to comment, I know the headstock should be held in the front of the jig. As Mr. Sinatra said: "I did it my way", checked the trueness of the frame and welded the downtube and bottom rails to the jig. Trueness was checked throughout the building and welding of the frame.
As I am not a professional welder, I only tacked the tubes together. This was then TIG-welded professionaly by a friend.
The simplicity of the design showed when it came out of the jig.
Time to get it back on its wheels, so a pair of old CB450 wheels were fitted.
The frame needed more strengthening, so two tubes in front of the rear wheel (top ans bottom) were put in:
A mock-up engine went in and it was time to see where the seat was going to go. Note the position of the original footrest... Way too high!
So the footrests were lowered, the sidestand shortened, the rear brake-mechanism was build (from some CB500Four and CB350K4 parts I found), the rear fender (aka original front fender) was tweaked to closely follow the radius of the tire and fitted.
Time to go back to the welder and get it all welded up professionally. First the top:
... and then the bottom:
A lot more work has been done since, updates will follow shortly. Enjoy!