More handbrake woes...
When I moved the guide tubes up to compensate for having dramatically lowered the back of my Vitesse chassis the following observation was made regarding the effect that might have:
andrewhush wrote:
You might have them a bit high. Ideally the end of the curved guide where the cable emerges to head off towards the wheel needs to lie on the axis that the lever end is rotating about as the wheel moves up and down. That is approximately a line joining the centre of the driveshaft universal joint and the front end joint of the trailing arm that is fastened to the chassis outrigger. A quick way to test is to take off the rear spring and raise/lower the wheel and see if the cable becomes slacker or tighter. As you have it at the moment I would expect one side to cancel out the other when the car rolls in cornering, slacken both sides when going through a dip and tighten when airbourne!
So, I reassembled everything this morning, adjusted the handbrake so it operated on four clicks of the handle and jacked the rear suspension up with it off. The cables tensioned and pulled the back brakes on solid.
After a bit of modification - lowering the guide tubes to half way between where they started and where I'd put them plus some extra strengthening here and there to stop the brackets flexing under tension I arrived at the follwing set up -
Adjusting the cables and jacking it up again, the back brakes locked solid again.
This time I had a really good look at what happens when the Herald/Vitesse swing axle suspension moves.
Weight on, tops of the brake drums are 110cm apart -
Weight off, tops of the brake drums are
113cm apart -
So, because the levers are at the top of the drums, jacking the car up tensions the compensator cable by 3cm no matter where the guide tubes are located, and this appears to be a flaw in the original Herald/Vitesse design.
This means either putting up with the rear brakes binding when you get some air under the back wheels or having the cables so slack you have to pull the lever up eight clicks to engage the handbrake.
Can anyone tell me if the car will fail the MOT if the back brakes bind when the back is jacked up?
Your thoughts please.