CANTILEVER SUSPENSION SYSTEM

Press, Volume CXV, Issue 33803, 27 March 1975, Page 24

CANTILEVER SUSPENSION SYSTEM

The search fo” greater movemer' rear suspensions motocross Cc.upetition machines has resulted in some rather ingenious shock absorber layouts. One of the most impressive of these is at present being tested by the former New Zealand scrambles champion, David Burns (Christchurch), on his Jean Machine CR2SO Honda Elsinore.

The new suspension system, which is of the cantilever variety but uses stock Honda parts, has created tremendous interest throughout New Zealand and already copies are starting to appear on the racing circuits. “The bike tracks dead straight and the power gets down on to the ground a lot better than it did with the original suspension,” Burns said.. “It is quite outstanding.”

All that has been necessary since the suspension made its first public appearance at Teddington during a South Island gold star scramble meeting earlier this year is the fitting of stronger springs. The new suspension is

the product of Burns's desire for a more competitive mount and the engineering talent of another former national scrambles champion, Alister Sabiston, also of Christchurch. Burns originally approached Sabiston, well known for his ability to manufacture complete motor-cycles of a high quality, and asked him to move the rear suspension units forward.

However, Sabiston suggested trying something entirely different — a cantilever system using standard components. Burns and his sponsor agreed to hand the Honda over to Sabiston. The result was the very efficient but relatively simple rear suspension Burns now uses.

The beauty of the new system is that, it utilises, in the Honda’s case, ordinary Honda parts which are easily obtainable. The standard suspension units are fitted to a small frame welded to each swinging arm. These are angled forwards, inside the frame. A 7in section had to be cut out of the sub-frame of the Honda and some pipe bending was necessary to get the units inside the frame but it was, relatively speaking, a simple operation for a skilled craftsman.

“The average person might not be able to do the modification but any major firm could handle it,” Burns said. He estimates that the total cost of the modification is $2OO. He feels that this is quite reasonable when it is considered that it lifts the Honda into the same class as the YZ Yamahas, which are produced with cantilever suspension.

The total movement of I the rear unit is now Bm, compared with 4Jin of the original. This is about an inch better than most modified units being used in Europe.

Burns is one of the most; experienced motor-cycle racers in New Zealand. He ; spent eight years racing; moto-cross in Britain and! on the European Continent.! Before that, he gained no less than 60 placings in New Zealand and South Island championships. He has lost count of the number of titles he has won.

He has also made his mark in road racing. When he was only a teen-ager, he won the New Zealand senior and junior grand prix titles on a pair of Nortons at Cust. He later dropped out of road racing to concentrate on scrambling. Since returning to New Zealand two years ago Burns has raced only as a

form of recreation. However. the new Sabistoninspired suspension might well re-kindle his enthusiasm for serious racing. The picture shows the degree of inclination of the rear shock absorbers on Burns’s Honda. These are normally out of sight behind the side covers.