This thread will not be to everyone's taste.
It's contents will provide a comprehensive strategy to improve the handling characteristics of a twin-shock air-head ÔÇô
a not entirely my own and not-so-secret "BMW Road Kill Cafe Recipe".
A plethora of information, mis-informatiom, and idle after-market advertising hype exists regarding this topic,
and together, maybe we can sort it all out.
All discussion is welcome, but please note:
My recipe, after all, is not intended to be THE definitive menu but rather just an example of one rather tasty "dish" ...
an inexpensive dish that would suit my taste, may suit yours, but will still prove too spicy for many.
So, if "spicy" ain't your style ... perhaps best to pass this one up ...
for the rest, let's get on with it then ...
The twin-shock air-head chassis was designed by the factory with then available technology
to be flexible in order to cope with a variety of road surfaces and conditions,
to be fairly competent in all possible riding situations, albeit extremely proficient in none.
As good and well received as this marketing strategy was,
it remains a compromise intended to appeal to the largest number of potential customers / riders most of the time.
The truth of this statement will be witnessed by the extensive chassis modifications that altered the Butler-Smith / Udo Gietl 1976 R90S
in order for it to be a successful competitor and Superbike championship winner.
The first point to note, then, will be that
modifications here are intended to improve chassis behavior when ridden fast on paved roads,
and that performance on dirt roads and marginal surfaces will likely suffer.
The resulting chassis will be more focused ÔÇô and less versatile.
Next, THE FIRST & ONLY PLACE TO START WITH CHASSIS IMPROVEMENT
WILL BE A STOCK CHASSIS THAT IS OPERATING AT 100% EFFECTIVENESS.
If your riding skill and style does not approach or surpass the limits of stock chassis design capability,
any improvements to the system will prove moot.
And finally, improvements will be relegated to stock components as if we were considering building a bike
to (loosely) satisfy AHRMA Vintage 750 Sportsman Class rules relative to chassis modification ÔÇô
i.e. no late model forks system transplants, custom frames, or mono-shock conversions.
Why do I emphasize "twin-shock chassis" ?
Because the factory effectively dealt with many, but not all, of the issues we will address here
with the introduction of the mono-shock platform and improvements continued
throughout the rest of the air-head model run.
The motorcycle chassis and chassis dynamics must be considered as an INTEGRATED SYSTEM.
Having said that, I will attempt to order this recipe in hierarchical terms of (my perceived) importance.
I will deal with these three sub-systems individually ÔÇô
Part 1, forks system and front suspension,
Part 2, main frame, and
Part 3, sub-frame and rear suspension.
stay tuned ... Part 1 to follow ...