6 plate clutch help

[joe swoonara]

your thoughts please , after a gearbox bearing failure i had to change the crownwheel
so opted for an MB version it takes 6 clutch plates and teamed it with a Foxhat extended spider,so now it`s all built up and amazingly i have No drag and No slip .........but there is No "feel " either !! Tried both MB and CamLam springs (they look identical)
Any ideas ??
it`s a TS1 240 5 speed Cyclone

[Warkton Tornado No.1]

Hi.

Unfortunately, this response is in agreement with your findings & not a solution.

However much that may be ‘crammed’ into whatever space is available, the fact remains that Innocenti designed the clutch release mechanism to only supply sufficient movement to allow for the separation of just four clutch friction plates.

The fact that certain six & seven plate clutches is able to operate within that space may be an indicator that the quality of the components utilised is superior. By that, I mean you have to wonder whether the Innocenti based components are as consistent as modern motorcycle based clutch parts with regards to flatness of the steels & even the compliance of the friction plates.

The cam itself that pushes on the release only has a finite radius & if you were to manufacture a larger one, the operating arm would need to be moved laterally to allow for the greater radius.
That won’t help you right now, though.

For you, if you didn’t know it, ideally, the cam needs to be set so that it has its greatest ‘throw’ when fitted.

It can be done by fiddling with the bronze pad on GP covers but is easier with the other type as you can shim beneath the release button or grind it away if necessary.

Your problem is nothing new. Many years ago, I recall Mark Ellis telling me that he had cut away a clutch cover so that the insides could be seen in a dry build of six plate race clutches....

I hope to have helped!

Regards

[Adam_Winstone]

^... nice response (good info and food for thought).

The other element that I must add (I may have missed it) is that of lever and grip choice at the bars. The very last of the GP levers, as per small ball end, had a revised profile (same as continued with by the Indians), which sweeps back towards the grip... great for people with small hands and when used with the limited travel of the standard 4-plate clutch assembly, however, this soon becomes the limiting factor when trying to use such a lever with a deep basket 5/6 plate clutch. If you have one of these levers fitted, which many scooters do, then you do not get the travel required and you end up with it too loose (does not disengage fully) or too tight and you get slip, followed by heat and binding. Either way your clutch will not function correctly and you will suffer slip, drag or burn it out!

Compare clutch levers one on top of the other and you soon see the limiting arc of the profile.

The other daft thing to fit are balloon grips, which limit lever travel regardless of type of lever fitted! (MODs beware!!!)

Adam

[Simon ELC]

I have a very similar set up to Joe. FoxHat 6 plates, same motor and gearbox. I have an Li type ramp and clutch set up (which I prefer). Not sure what Joe's lever, cable and grip set up is but mine is:- Nylon lined cable, Yamaha lever modified (By me) and Renthal grips. Easy action and loads of feel.

Ps. Clutch plates are six green plates and 1.2mm steels. Can't remember what springs.

[Warkton Tornado No.1]

Hello again.

As Adam says, the lever on the bars does make a difference, but unfortunately there isn’t an awful lot to be gained there.

However, he reminded me that I neglected to mention the other racer’s trick of utilising a cut down clutch arm lever (cut & shut welded.) This modification is well worth doing.

I have also played about with the position of the clutch arm lever because, if you think about it, you gain more angular movement if you start with the lever nearer the rear of the machine than, say, @ almost ‘square’ to the cable.(I hope I haven’t ‘lost’ anybody there!)

The best that you can do is to optimise everything as much as possible:
Good friction plates
Good steels
Good handlebar lever
A good inner cable (rope) & nylon lined rectangular section wire outer
The release cam set to maximise the movement.
A shortened clutch arm lever.

Although I run a six plate in my road bike, for racing (if I ever get back out there) I recently modified a motorcycle six plate clutch which appears to work well & hopefully will be beneficial as far as gearbox life. For many years, I found that when my race bikes are put into gear & there is only just enough clearance/drag, the teeth on first pay the price.

Although a complete motorcycle clutch of fantastic quality & consistency can be acquired from eBay for a fraction of the cost of any Lambretta type, there is a large amount of engineering required to make one fit.
That’s one reason I won’t be divulging the type that I use....

I hope to have helped & not been too technical.

Kind Regards

[joe swoonara]

thank you all for input and especially Mr.Tornado what a fantastic and very helpful reply , i have taken note of your suggestions on the clutch lever and moved in one spline back toward the shocker , the lever on the other end , handlebar is a standard series 2 , clutch plates i`m using are green surflex and 1.2 mm steels , now having moved the lever backward and taken it for a little run up and down the driveway the results seem promising , but will get out for a long road test later in the week