Heavy Clutch

[Chris Hubball]

Learned Gentlmen

 

I have converted my TR 4 to a Diaphragm Clutch in the hope of it being lighter than the spring type , which has been partly achieved , but `er` in doors still complains its still heavy. I have heard that changing the Master Cylinder from a .75`` bore to .70`` will make a further improvement has anyone done this ? and is the improvement noticeable

 

Cheers Chris.

[Fireman049]

Hi Chris ~

 

What condition is the clutch flexible hose? If it's quite old there is a possibility that it may have partially collapsed internally making for a heavy clutch.

 

Tom.

[Chris Hubball]

Hi Tom

 

Its the uprated stainless steel braided type not the standard rubber variety .

 

Cheers Chris.

[Lebro]

You may notice a small drop in pedal effort, but you will also need to push it further down to release the clutch.

Bob

[Z320]

I have heard that changing the Master Cylinder from a .75`` bore to .70`` will make a further improvement has anyone done this ? and is the improvement noticeable

 

Cheers Chris.

Hi Chris,

 

I did that on my TR4A against everyone telling me it will not work because of the more way you need for that.

But with the 0,75" master cylinder there was more than enough way, so I did it.

With the 0,70" cylinder I indeed have some more way but it works lovely, it is an wonderful improvement (but still stronger than on modern cars)!

But this result perhaps is caused by the components on my car, check if you have "more than enought" way on your TR4 .

 

Ciao Marco

[Z320]

BTW,

you need 12,888% less force (1,00 - 0,7²/0,75²) x 100

but 14,796% more way(0,75²/0,7² - 1,00) x 100

[Z320]

Sorry, I had doubts about my post,

because the improvement I realise is more than 12,888%.

Looked for the bill - I use the cylinder of the Reliant 600/700, this is only 0,625' bore!

So I reduced from 0,750' to 0,0625', that's about 30% less force.

[Z320]

to 0,625' = 5/8'

[Z320]

still can not edit my posts or only a minium time

[TriumphV8]

The problem with the force is not from pipes but from

mechanical friction and angles of levers.

 

I did a lot with smoothing all parts, fitting larger brass bearings

and bringing all into perfect position.

It helped a lot, I was close to a modern clutch.

 

Unfortunately that did nor last long although all is still easy going

especially compared to the Mcleod performance Clutch in the V8.

 

So one can be pleased with the forces especially with the 0.70" cylinder

but the joker is the Howe center release throw out bearing like modern cars have.

 

Over the winter I will do one or two swaps with that system

for clubmates with handicaps.

 

http://howeracing.com/index.php/store/drive-train/throw-out-bearings/howe-hydraulic-bearing-for-racing-clutch/throw-out-bearing-hydraulic-racing.html

[RogerH]

Hi Chris,

I've been away on hols and have just seen your query.

My 4A was quite heavy and eventually had ratchet clutch (kangaroo'ing)

 

I fitted a bog standard Moss B&B type pressure and friction plate.

I fitted the TRShop steel bearing carrier and the Moss RHP expensive bearing.

Doubled up on the cross shaft bushes.

The slave cylinder is always out of alignment so mad a new Slave Cy holder that put the piston rod where it needs to be.

Lubricated the splined shaft for the friction plate and lubricated the bearing carrier extension snout.

I also check the alignment of the splined GB input shaft with the extension snout (bearing carrier sleeve) this was out by 15' and was the cause of the ratchet clutch.

Make surer ALL pivots and holes are the correct shape and not worn.

Standard Master/Slave Cy's

 

Roger