Clutch pedal travel
Discussion
It's quite heavy but like Nick says it does get easier with use (and not just because the leg muscles build up). I do a lot of cycling so it doesn't bother me too much though I do find I stick the car in neutral a lot quicker when running in traffic than with a "regular" car. 
I discovered something not so great with my clutch at the weekend. I took the car to a dyno session organised by some guys from the PH Scotland section a week or two back. The dyno guy complained about my clutch dragging a bit on the slow down run (to estimate engine/gearbox losses). I've had a good look over the clutch and it looks like it is the way it is meant to be and the throws are correct, etc. However when I took the pedal to bits to check it I discovered that the bugger had pushed so hard on the pedal he's bend the connecting rod on the clutch master cylinder!
Grrrr. I guess it's all my own fault for not making sure that at max pedal travel there wasn't a lot of clearance between the pedal and the bulkhead. Hey ho. I'm glad they're not expensive.
I discovered something not so great with my clutch at the weekend. I took the car to a dyno session organised by some guys from the PH Scotland section a week or two back. The dyno guy complained about my clutch dragging a bit on the slow down run (to estimate engine/gearbox losses). I've had a good look over the clutch and it looks like it is the way it is meant to be and the throws are correct, etc. However when I took the pedal to bits to check it I discovered that the bugger had pushed so hard on the pedal he's bend the connecting rod on the clutch master cylinder!
Grrrr. I guess it's all my own fault for not making sure that at max pedal travel there wasn't a lot of clearance between the pedal and the bulkhead. Hey ho. I'm glad they're not expensive.
Will check this properly when I fit the new cylinder. Just a quick update. I took my whole clutch pedal assembly to pieces at the weekend in an effort to fix the problem. Once I'd had a look at the master cylinder the shaft didn't seem to be too badly bent so I decided to straighten it. I looked at the slot in the back of the clutch pedal and sure enough it had been fouling the clevis and that's why the master cylinder shaft got bent. Bit of careful filing soon made the hole a bit wider and about 5-6mm longer to be sure of clearing the clevis in normal operation.
When I reassembled everything I tried to set it up to have the maximum throw possible. I couldn't quite manage to get the full throw of the master cylinder with the pedal against the bulkhead. Decided to rebleed the system and try it anyway. With the engine running as I slowly pushed the pedal towards the floor...heard a nasty banging sound as the clutch/flywheel bolts started to touch the release fork! This was just as gdr described last year. I then adjusted the pedal to have about 4-5 mm less throw. Tried it again and this time no funny noises at all. As a final check I put the car in gear (on axles stands) and got someone to check that the wheels were not starting to turn. No clutch drag at all.
Took the car for a quick test drive and the change is dramatic. Clutch is much much lighter. I had a niggle with being unable to put the car into 1st when moving which has gone away (it's not something you do very often so I hadn't been worried about it). Changing gear is a little smoother than it used to be in general. I expect the clutch drag I saw on the dyno last month will now have gone away completely.
I think I must have bent the master cylinder shaft the first time I pushed the clutch pedal home when it was dry. It's very worth while double checking that the clutch pedal movement is as smooth and snag free as it ought to be. I think it would be possible to go to a 5/8" or 0.7" master cylinder to get a lighter pedal that can use the full throw.
When I reassembled everything I tried to set it up to have the maximum throw possible. I couldn't quite manage to get the full throw of the master cylinder with the pedal against the bulkhead. Decided to rebleed the system and try it anyway. With the engine running as I slowly pushed the pedal towards the floor...heard a nasty banging sound as the clutch/flywheel bolts started to touch the release fork! This was just as gdr described last year. I then adjusted the pedal to have about 4-5 mm less throw. Tried it again and this time no funny noises at all. As a final check I put the car in gear (on axles stands) and got someone to check that the wheels were not starting to turn. No clutch drag at all.
Took the car for a quick test drive and the change is dramatic. Clutch is much much lighter. I had a niggle with being unable to put the car into 1st when moving which has gone away (it's not something you do very often so I hadn't been worried about it). Changing gear is a little smoother than it used to be in general. I expect the clutch drag I saw on the dyno last month will now have gone away completely.
I think I must have bent the master cylinder shaft the first time I pushed the clutch pedal home when it was dry. It's very worth while double checking that the clutch pedal movement is as smooth and snag free as it ought to be. I think it would be possible to go to a 5/8" or 0.7" master cylinder to get a lighter pedal that can use the full throw.
GTRMikie said:
I've just changed my clutch master cylinder to a 0.625" and it has transformed the car. The pedal is lighter and the car is much easier to drive in traffic. The increased pedal travel results in a much smoother take up of the drive.
Exactly my findings when I did same thing. Also, not possible to over extend the clutch fork into cover bolts with smaller master cyl.
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