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Default Does a tyre change its CIRCUMFERENCE when underinflated?

"Rod Speed" wrote in message
...
Yes, but doing that clearly didnt see my Golf need a new one in
more than 45 years of daily driving, or even see the grab point
change as far as the pedal position changing is concerned either.


I won't say outright that I simply do not believe you when you say that you
drove a Golf for 45 years and in that time the bite point didn't change,
even though auto-adjusting clutch mechanisms were probably less common in a
car of the age of a Mark I Golf from 1973. But I am very surprised.

The amount of slippage depends on the effective weight of the vehicle (ie
mass times sin(gradient angle)) and the engine speed. You try to minimise
this by a) keeping the engine revs as low as you can without stalling,


I dont.


So you don't minimise the engine revs...

b) letting the clutch up as fast as possible without jerking the car so
it spends a minimum time slipping, and c) not applying much power until
the clutch is fully engaged.


I dont do that either.


.... And you don't minimise the time that the clutch is slipping (neither
fully disengaged nor fully engaged).

And yet you've had a clutch last 45 years, even without taking those
precautions?

Other gearchanges *theoretically* cause no wear if you manage to match
the engine speed to the road speed in the new gear. I'm probably not
*too* bad at getting it close, but I'm not perfect - my "good" to
"cocked-up" gearchange ratio is high but not 100% ;-)


Cant remember the last time I ever stuffed that up.


But I bet (unless you are superhuman) you won't be as good at matching
engine to road speed in new gear, accurately and consistently, as a DSG
gearbox will be. I only claim to be good; I don't claim to be perfect.

Bugger all carparks have the cars parking up to a brick wall.


Now that really is a daft statement - so easily disproved. Most small
non-supermarket car parks have a row of cars parking against the wall of a
building and maybe some against a boundary wall between the car park and a
pavement. Most multi-storey car parks have some cars parking against the
outside wall - OK, it's probably concrete rather than brick, but let's not
be picky.