Hydraulic clutch

I suspect a lot of our differing experiences with the Commando clutch are related to not only our perceptions about what constitutes a heavy clutch, but also to physical differences. I raced Commandos with stock clutches (both organic and sintered bronze) for quite a few years when I was younger, and never really noticed a problem with clutch pull. They were certainly much heavier than the various Japanese bikes I also raced, but it didn't bother me much. I did convert one of the race bikes to hydraulic, and appreciated the improvement, but could have managed without it. Besides just getting older and feebler in the years since, I've also had hand surgery (both hands) that left me with only 60 - 70% strength left, so now I'm much more sensitive to the clutch pull force required. I'm still mostly ok with a stock Commando clutch with a good cable and proper maintenance, but I do encounter hand cramps if I have to use the clutch a lot. If I can lighten it up more by playing with the stack height, or going to hydraulic, I will do so, just to improve the quality of the riding experience.

It also seems fair to point out that there is a limit to the amount of torque the Commando clutch will handle before slipping. What works for a stock 750 might not hack it with a built 920. Adjusting the stack height for more static pressure to avoid slipping will increase the pull force at the lever. I've run into that problem a couple of times now.

And as comnoz has pointed out, there are several different spring rate diaphragm springs that have been used over the life of the Commando, which might also explain why some stock Commandos have a lighter pull than others.

Just sharing a few rambling thoughts about Commando clutches, not arguing for any particular position.

Ken

"The key point to the Magura units is, is a 10mm throw enough for the Norton clutch release lever to function. They say if you need more, it won't work.
Then I would need the switchgear to add to the expence. Venhill offers a nice one of these too. "

Those 10mm had me wondering too, seems a bit short? But then again, people are obviously using them, so it has to work. Since English isn´t my native language, I´m sometimes thrown off by some expressions, and it doesn´t make things easier when there´s two different ( or maybe even more, don´t know about you people "down under", do you have a third mechanical vocabulary?) types off English :? So switchgear means? I actually searched the Venhill site for "switchgear" but nothing came up. Sorry about this, but I´m learning....
Tommy

fiatfan said:

"The key point to the Magura units is, is a 10mm throw enough for the Norton clutch release lever to function. They say if you need more, it won't work.
Then I would need the switchgear to add to the expence. Venhill offers a nice one of these too. "

Those 10mm had me wondering too, seems a bit short? But then again, people are obviously using them, so it has to work. Since English isn´t my native language, I´m sometimes thrown off by some expressions, and it doesn´t make things easier when there´s two different ( or maybe even more, don´t know about you people "down under", do you have a third mechanical vocabulary?) types off English :? So switchgear means? I actually searched the Venhill site for "switchgear" but nothing came up. Sorry about this, but I´m learning....
Tommy

Click to expand...

Yes, switchgear can be misleading having more to do with backup electrical systems(generators).
http://www.venhill.co.uk/Controls,_Leve ... WITCH.html

fiatfan said:

it doesn´t make things easier when there´s two different ( or maybe even more, don´t know about you people "down under", do you have a third mechanical vocabulary?) types off English :? So switchgear means?

Click to expand...

this page has some of the UK-US terminology equivalents

technical-information-how-post-photos-t2357.html

And as comnoz has pointed out, there are several different spring rate diaphragm springs that have been used over the life of the Commando, which might also explain why some stock Commandos have a lighter pull than others.

Just sharing a few rambling thoughts about Commando clutches, not arguing for any particular position.

Ken[/quote]

All good Ken, not every Norton clutch is the same, some have light clutches and other have very heavy clutches, I have sorted out a few clutch problem with mates that have had Nortons over the years from slipping to being to heavy and each clutches I have worked on have had diffrent fixes, most of the problems with most is lack of maintenance or using motor oil in the primary, I have only worked on the kick start models, so far haven't had the chance to work on a M111, but one day hopefully just for the experance.
I find the Commando clutches are a simple set up and work well, I am going to run a Commando clutch and belt drive in my project bike (1960 650 Manxman built as a caferacer) but not sure how it will handle without the shock rubbers, only time will tell.

Ashley

pete.v: Thanks, this means I´ve learned todays new word!
gortnipper: I´ve seen that list before, think it´s in one of the workshop manuals I´ve downloaded. But there was no "switchgear" there.... :wink:

Tommy