Quiet on the blog but it has been busy in the workshop with a number of projects progressing. My VSCCS application has been approved in NSW and I am just waiting on a response from the WA Department of Transport. And the picture? Well one of the projects in progress is a rebuild of a 1974 Honda QA50. This is the engine casing after a quick bead blasting.
This makes it very difficult to bleed the brakes but worst of all it is down right dangerous!
I was recently tasked with reconditioning a Honda CB-500 Four that had been left in the weather for a few years. When I saw the bike one of the first things that I noticed was the “front brake reservoir delete” or in simple terms a piece of Tygon tubing with a plug in it. I wasn’t impressed but had seen something similar plenty of times on the motorbike blogs and on race bikes.
Then when I went to bleed the front brake I had one squeeze of the lever (with the bleed nipple open) and then nothing. No brakes. No pumping. Nothing and the tube was still full of fluid. Continue reading Please Don’t Ever Do This!→
As mentioned previously on this blog, this is a motard style conversion of a Honda CRM 250 using a 2007 model Aprilia RS-125 wheels, discs and front brake caliper.
A custom bracket was designed in Solidworks to adapt the radially mounted caliper to the original brake caliper mounting holes. Designing in 3D allowed the part to be simulated (FEA) with heavy braking loads and calculate the factor of safety, stress, strain and distortion.
The APRILIA RS-125 caliper has finally been installed on the Honda CRM-250. The brake system has been bled with a quality DOT-4 brake fluid. It now has a solid feel (though there is some sponginess due to brake hose expansion – this may be replaced with a braided line) and no leeks in the system. So far low-speed testing has been carried out with further testing to come.
A recent project was figuring out how to adapting a YZ-125 motorbike engine to a go-kart frame.
A kart usually has two parallel tubes to mount an engine to sometimes a flat plate that is welded into the frame. A motorbike on the other hand has a frame that encircles the engine or even uses the engine as a stressed member forming part of the chassis. The kart for this engine had a flat steel plate with a few slotted holes to bolt the engine in place and was situated behind the axle close to the centerline. Continue reading Adapting a Motorcycle Engine to a Go-Kart→
The calipers have been dis-assembled and inspected. The castings of the inner and outer caliper halves are symmetrical, front to rear, and could be machined to suit either the left or right hand side fork of the motorbike.