Development
The Panther sloper engine designed by Granville Bradshaw remained unchanged for 25 years and the 650 cc 'heavyweight' had many of the Model 100 components. The increased capacity was achieved by boring out the Model 100 cylinder by 1 mm and increasing the stroke by 6 mm. As well as increased low speed torque this improved acceleration and top end cruising speed.
This put additional strain on the main bearings and crankcases, leading to reliability problems. The 120 also suffered with lubrication problems from the large sump cast into the front of the engine. Oil was pumped to the top of the sloper engine but return was erratic and oil consumption very heavy. The main shaft was redesigned with larger ball journal main bearings, A smaller exhaust valve combined with a larger Amal monobloc carburettor gave the Model 120 28 bhp at 4500 rpm, an increase of 4 bhp over the Model 100.
Motorcycle sidecars were popular at the end of the 1950s, so the Model 120 was provided with a purpose built sidecar chassis, connected by a three point mounting which provided minimal alignment problems. The sidecar wheel was interchangeable with the motorcycle wheels and had swinging arm suspension with an Armstrong shock absorber. A trailer with a towbar was also provided as an option.
Read more about this topic: Panther Model 120
Famous quotes containing the word development:
“Other nations have tried to check ... the fulfillment of our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions.”
—John Louis O’Sullivan (1813–1895)
“For decades child development experts have erroneously directed parents to sing with one voice, a unison chorus of values, politics, disciplinary and loving styles. But duets have greater harmonic possibilities and are more interesting to listen to, so long as cacophony or dissonance remains at acceptable levels.”
—Kyle D. Pruett (20th century)
“I could not undertake to form a nucleus of an institution for the development of infant minds, where none already existed. It would be too cruel.”
—Henry David Thoreau (1817–1862)