This blog has been created, in response to numerous requests, to document some of the stuff that I play around with. This will mainly be frames and engine parts for my own Aermacchi classic racing bike, but at times will also include the tools needed to make these parts. The initial posts will be looking rearward in time to lay the foundation for current and future work. There are more pix. on my Picasa page and web site at http://www.tonyfoale.com and http://picasaweb.google.com/tonyfoale
Saturday, 5 September 2015
Thursday, 9 July 2015
SEMINAR BARCELONA SEPTEMBER.
Over the past few years I have had a number of people asking me to give a motorcycle dynamics seminar within Europe. For various reasons this never happened. However, providing that there is sufficient interest I intend to give one during August or September in Barcelona. It will be a two day event and details of subject matter etc. can be found on my web site www.tonyfoale.com Email me on info@tonyfoale.com to express an interest and/or request more info. Also indicate any preferred dates and whether weekend or week days are better. Barcelona is a beautiful city with much to see and do so come and enjoy. BTW the seminar will be given in English. Please share this post.
Sunday, 21 June 2015
Friday, 6 February 2015
I have recently been contemplating the optimization of the performance of drum brakes for my classic racing Aermacchi. I have also been in discussions with a couple of friends regarding improvements to a drum brake for a road bike.
To put this work on a more technical but easy to use basis I have developed a small computer programme to evaluate the effects on braking torque of changes to the overall drum and backplate geometry and changes to the coefficient of friction.
As this software might be of use to others I have made it freely available and it can be downloaded from the freeware section of my web site at www.tonyfoale.com
It is a single standalone .exe file so just download it to a directory of choice and run it directly or make an appropriate shortcut to it. No installation procedure is necessary.
Wednesday, 24 December 2014
Why are dirt bike riders supposed to be tall?
Recently I lowered the seat height on my Honda XR400R. It was needlessly high, adding suspension movement on top of the tyre diameter still left a lot of excess space. Shortening the sub-frame down tubes would allow the bolted on sub-frame to rotate downwards from the top mounting lowering the rear of the seat by a considerable amount, although not so much at the front area of the seat. Dropping the rear makes it much easier to get on and off the bike and I later removed about 30mm from the thick foam to lower the seat overall. For a 1.75m high rider (me) subsequent riding confirmed the benefit of the lower seat.
Original subframe showing where it was shortened.
Lowered subframe.
If only things were that simple. The lowered subframe meant that the air filter moved closer to the carb, but that wasn't a problem, the flexible coupling easily accepted that. The problem was that the airbox now fouled the shock. For obvious reasons I didn't want to move the shock so I had to cut away part of the airbox which leaves an entrance for water ingress when riding across rivers. I think that I'll have to make a new box in CF.
Another thing to fix was that the relationship between the subframe and muffler and its mountings was changed. I had to modify the muffler pipe to align everything again, not a big problem.
I found a short piece of steel tube in the airbox, it turned out that a cross tube on the top of the subframe had fractured due to a lack of proper bracing by Honda, and had fallen into the air inlet. In other words the subframe was not sufficiently rigid in a lateral direction. Continuous flexing had lead to the fracture. To improve on this rather than just replace the broken tube I welded in a diagonal bracing tube as well as a new cross tube.
Welding in the bracing tubes.
Cross tube and diagonal brace.
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