"g.daniels" <[email protected]
> wrote in message
> Paul! the Suntour derailleur threads through a steel hanger then fixs to the hanger with a thin
> nut on the side opposite the derailleur. the derailleur pivots on the bolt shaft whose head forms
> a broad bearing surface that locates the bolt/derailleur assembly 90 degrees to the hanger. the
> hanger itself attaches to the dropout with a rather small metric screw as the hanger is forged
> with a space for the axle in this hanger area. whew!
> that a new shimano deray bolts into this efficient antiquo design would be remarkable.an agreement
> exists of a manufacturers consortium specifying common lengths, widths, thread sizes- any idea if
> the text exists on the web?
> one design feature that escapes me are the two threaded areas, one on the hanger, one one the nut
> opposite. whazzit do?
The early Suntour rear changer design did not incorporate a top pivot spring. The top bolt is
screwed in (lube first!) and then adjusted so it can pivot without sideplay. Hold the top bolt with
an allen key and lock the locknut (behind the plate) with a 17mm wrench. Check for free motion, no
sideplay , and correct as needed.
Simplex used a similar system to adjust top spring tension.
Andrew Muzi http://www.yellowjersey.org
Open every day since 1 April 1971