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Comment by VorpalWay | Hacker News Reader

Why was the clutch so heavy? Did it serve some purpose or was it just due to the limitations of the technology at the time?

I have certainly driven cars with lighter and heavier clutches (I live in EU, automatics weren't popular until recently and are still far from ubiquitous) but I couldn't tell you why every model just doesn't get a light clutch for comfort. A diesel Subaru I drove had a particularly heavy clutch as I recall, so at stop lights I would pop into neutral instead of holding the clutch down for an extended period.

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To deliver very high torque, the clutch plates needs to be pressed very hard together to generate enough friction. This also means that it take a lot of force to pull them apart, if you use a simple lever, as older machines do.

Modern machines may use complex mechanical linkages to make the clutch easy to pull apart but still maintain a firm contact, but that also means higher cost and fragility. Or they use pneumatics or hydraulics to assist, sorta like power steering.

That, and design tolerances. A fancy clutch can be light and strong (think ferarri) but farm machines need to work in the dirt/rust and so need larger tolerances. So heavier springs and bigger .... Bigger everything. A slipping clutch in a Ferrari is annoying. A slipping clutch on a tractor means a missed harvest.

Plus mechanical release mechanisms of heavier machinery were often designed in a way that the clutch snaps at a certain point (also in order to reduce wear in the clutch).

Also because farm machines usually need max torque fast to break loose from static friction. You want a clutch to bite hard when pulling things through mud.

I once changed a broken release bearing of a truck. It was a relatively simple repair but the very heavy gearbox has to be taken out to do this - which is problematic especially if done on a yard without proper equipment.

Since then I always pop into neutral when standing at a traffic light. It is interesting how many people in manual driving cultures think there would be no wear and tear if they press the pedal down completely.

Of course there is, as there has to be a force translating connection between rotating parts and parts of the release mechanism which cannot rotate. Only when the pedal is left alone, the release bearing disconnects from the rotating clutch.

As a motorcyclist stopped at the traffic light I always keep the gear on and clutch pulled in. Why? Because I have to be ready to take off when the moron driver on the phone behind me fails to stop.

This is how I was taught by my insurance-recognized course and for the same reason you provided.

I believe wet clutches are semi-designed with this use-case in mind

I do the same thing, and I rationalize it with the fact that the clutch in my motorcycle is is constantly bathed in oil so it can take the "abuse."

The release bearing might not be

I don't ride anymore, but I always did the same at least until a few cars were at a dead stop behind me.

Fair

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