Damper tamper

Feb 2014 – issue 212. May I be so bold to make a few points? Speedos, an excellent article but a bit beyond most of us to do. I have had some success in adjusting the stiffness of the needle return spring by moving the soldered attachment point at the end of the spring nearer to the end. I suppose this compensates for the loss of magnetism in the spinning magnet. I then got the best calibration I could with use of SatNav at 35mph and 70 mph.

Page 52/ 53 ( Eric’s diary), ref Armstrong lever arm dampers. With an excellent comprehensive article on speedos the renovation of sludged up lever arm dampers was a contrast. It is actually very easy to adjust both bump and rebound damping when the valve assembly is out. The little washers/shims adjust the bump damping and the nut on the compression spring controls rebound damping. Although it is true that increasing the viscosity of the oil used will compensate for the typical leakage past the piston rings this is a bit crude. Quite good characteristics, for a lever arm damper, can be obtained by adjustment of the valves. I tend to increase bump damping until ride suffers over moderate bumps, and then adjust the rebound to control oscillation after a bump.

Page 108, "Worthy upgrades" on a Merc 230CE. And there was I thinking that stiffer dampers only controlled transients as one enters and leaves a corners so slows down the rate of roll and not as you suggest: "...cut body roll." The amount of roll in steady state cornering will be the same whatever your damper rate is of course.

Otherwise I love the variety of subjects you cover in one issue, glad to see another 'sliding pillar' suspension mentioned, even though it is the opposite of my favourite sports car - my Morgan of course.

Keep up the great work!

Peter J Ballard.

GS: Thanks Peter, in Eric’s defence, his diary was just that, not a tech feature. Next issue, however, you could be in for a lever arm-tastic treat.