Monday, 6 October 2014

Fixing the cheap and nasty (or "Doing it right")

Production bikes are generally built down to a price rather than up to engineering excellence.  This means that there are plenty of areas where improvements can be made. Usually people only think in terms of those big modifications which invariably cost a lot of money, such as new suspension, wheels etc.  However there are many small detail features that are equally important but which only cost a little time.  Sometimes these small detail fixes are necessary in order to provide a sound base on which to add the fancy bits.  Of course there is rarely any Bling benefits to be had from the small oft hidden changes.  We are all familiar with the term "blueprinting" when it comes to engines, but "blueprinting" the chassis is equally important.
The pix. illustrate just what I am referring to.  The Suzuki SV650 internal swingarm axle spacers cum chain adjusters are terrible bits of sheet metal poorly tack welded to a spacer. The external spacers are of too small a diameter and when the assembly is tightened, pressure is only applied to a very local area of the flat swingarm sides instead of the whole vertical face.  In combination with new larger diameter external washers/spacers the pictured chain adjusters provide a more rigid connection between axle and swingarm.

On the left is the original chain adjuster, the witness marks above and below the axle hole clearly show the limited area of contact with the swingarm.  The new block is shown to the right.

Front and rear of the replacement blocks.

Fitted block.  Note how the upward force from the axle is passed to the top piece of the swingarm section, also how the sides of the swingarm make full contact with the block.  Larger axle spacers and washers are needed as well to ensure a more rigid connection when the axle is tightened.