The Vintage Trials Thread - Page 22

Twin-shocker · 07-29-2012, 01:35 AM

Quote:

Originally Posted by Pete-NZ

Yes I have read about there conversion...
Sending my clutch half way around the world to get them to do what I can do myself is
not really a option..
Just need to find some plates that fit or are close enough to machine to fit...
Guess I will have to go anoy the guys at the bike shops... See what I can
come up with...

Never had a single problem with the all metal clutch on any of the Monts I owned back in the day, and its worth bearing in mind that the stock parts work, before fitting a conversion which very likely wont.

Diameter of the clutch on old Spanish bikes is very small, so I would guess that changing friction plate material and reducing spring pressure may well mean problems with slippage.

Pete-NZ · 07-29-2012, 01:53 AM

Quote:

Originally Posted by Twin-shocker

Never had a single problem with the all metal clutch on any of the Monts I owned back in the day, and its worth bearing in mind that the stock parts work, before fitting a conversion which very likely wont....

Diameter of the clutch on old Spanish bikes is very small, so I would guess that changing friction plate material and reducing spring pressure may well mean problems with slippage.

Its no drama if it dosn't work .. i will go back to the all steel stack..
I have a mod in mind that requires fiber plates...

Twin-shocker · 07-29-2012, 04:02 AM

Before doing anything, have a close look at whether or not its feasible to increase clutch release mechanism travel, as you will probably find you will need more travel as conventional friction plates expand when hot, and steel ones dont.

Personally I would have looked and altering the stock chopper steering angle, and adding a bit of length to the swinging arm on a 348, before getting involved with very fiddly engineering work to alter the clutch.

PSchrauber · 07-29-2012, 01:38 PM

Quote:

Originally Posted by Pete-NZ

Yes I have read about there conversion...
Sending my clutch half way around the world to get them to do what I can do myself is
not really a option..
Just need to find some plates that fit or are close enough to machine to fit...
Guess I will have to go anoy the guys at the bike shops... See what I can
come up with...

If you have the experience why did you ask?

I had send the flywheel of my KTM to Chuck Stealy in Medford Oregon (US) for adding some weight. From my location this is too half way around the earth. Beside the shipping duration and the shipping costs :/,
it worked out very well.

I tried to find someone here in Germany, but couldn't find anyone, the offers I got with an affordable price where without balancing out the rotor or where riddiculous expensive.

I have read somewhere - forgot where, (may be TC?) - that plates of the CB 125 should fit. But in my experience so far a replacement of the basket with better working plates and a modiefied pressure plate that fit's to the montesa engine is the best way to do it. Sure you can try out but if it don't work you will have to pay the double amount in effort, time and money ...

Twin-shocker · 07-29-2012, 02:02 PM

Thats strange...............looks a very simple job for anyone with a largish lathe, and some brass or bronze bar stock?

PSchrauber · 07-29-2012, 02:28 PM

Yes it looks easy but the rotor with the added weight needs to be balanced,
which is impossible if you don't have a balancing machine.

Pete-NZ · 07-29-2012, 03:00 PM

Quote:

Originally Posted by PSchrauber

If you have the experience why did you ask?

I have read somewhere - forgot where, (may be TC?) - that plates of the CB 125 should fit.

Sorry ..may not have been clear...
The question was......Dose anyone know if its been done
and what plates were used.....
CB125 plates... got to keep serching CB125 models... all the ones
I have found so far are 8 finger plates... need 12 to fit the Cota basket...
Found the XR125 has 12 finger plates , basicly the same motor as the CB125..

PSchrauber · 07-29-2012, 04:08 PM

Quote:

Originally Posted by Pete-NZ

Sorry ..may not have been clear...
The question was......Dose anyone know if its been done
and what plates were used.....
CB125 plates... got to keep serching CB125 models... all the ones
I have found so far are 8 finger plates... need 12 to fit the Cota basket...
Found the XR125 has 12 finger plates , basicly the same motor as the CB125..

As mentioned, Pfahler (in Germany) has found out a good working setup. But as he earns his money with that rebuild he hasn't told his ressources.

The topic in TC is found here: http://www.trialscentral.com/forums/...tch+%2Bmontesa

BTW: You haven't mentioned the model and year of your Cota?

Pete-NZ · 07-29-2012, 04:29 PM

Quote:

Originally Posted by PSchrauber

As mentioned, Pfahler (in Germany) has found out a good working setup. But as he earns his money with that rebuild he hasn't told his ressources.

The topic in TC is found here: http://www.trialscentral.com/forums/...tch+%2Bmontesa

BTW: You haven't mentioned the model and year of your Cota?

Its a 1977 348 that I'm rebuilding...

Twin-shocker · 07-29-2012, 10:26 PM

As a matter of interest how many times have you used your 348 in competition, and what leads you to thinking that a clutch conversion is needed on it?

Pete-NZ · 07-29-2012, 11:33 PM

Quote:

Originally Posted by Twin-shocker

As a matter of interest how many times have you used your 348 in competition, and what leads you to thinking that a clutch conversion is needed on it?

LOL.... your question has a shade of smart in it... but to answer question "50 metres"
I will answer the 2nd part aswell ..
I need a lighter clutch so it's easyer to use while standing...I can use it as is.. but
lighter would make it easyer...

Twin-shocker · 07-30-2012, 04:02 AM

Why not fit a new cable and extend the operating arm, then try the bike in competition and see how it works out? I owned 348 and 349 Monts back in the day, and if I was riding one today altering the chopper steering, and getting the suspension working better would be things I would be thinking of doing.

Sting32 · 07-30-2012, 12:42 PM

Quote:

Originally Posted by Pete-NZ

LOL.... your question has a shade of smart in it... but to answer question "50 metres"
I will answer the 2nd part aswell ..
I need a lighter clutch so it's easyer to use while standing...I can use it as is.. but
lighter would make it easyer...

Pete,

Mods we did in the heyday was to add 1/2 inch or there abouts, to the clutch arms at the transmission, more leverage means slightly easier pulling. Get new cables, they have more "slippery" (teflon? inserts) plus load them up with some good (become dry powdery) lubes. Make extra care to keep cables from making even remotely sharp turns... then also you can buy lever & perch combo that adds leverage at your fingers end of the cables.

Problem I find is, then it can be tedious to get enough slack to fully enguage clutch, yet enough movement at the arm at tranny area, to disenguage clutch, if you go too far on the bottom arm.

but it is all fine tunable. Then, get one of those hand squeezing things and build up your fingers, lol.

Twin-shocker · 07-30-2012, 01:20 PM

Very easy way to get a good clutch pull on older bike is to fit hydraulic clutch conversion intended for pit bike. Would probably need a longer hose, but they are very cheap and need no adjustment once fitted and set up properly.

Pete-NZ · 07-30-2012, 02:57 PM

[QUOTE=Sting32;19247296]Pete,
Then, get one of those hand squeezing things and build up your fingers, lol.[/QUOT

07-30-2012, 02:57 PM	#330
Pete-NZ Studly Adventurer Joined: May 2011 Oddometer: 508	[QUOTE=Sting32;19247296]Pete, Then, get one of those hand squeezing things and build up your fingers, lol.[/QUOT __________________ Here.... my XR250 leaner side car build http://www.advrider.com/forums/showthread.php?t=716993 Pete-NZ screwed with this post 07-31-2012 at 01:36 PM

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07-29-2012, 04:02 AM	#318
Twin-shocker Studly Adventurer Joined: Jan 2012 Oddometer: 993	Before doing anything, have a close look at whether or not its feasible to increase clutch release mechanism travel, as you will probably find you will need more travel as conventional friction plates expand when hot, and steel ones dont. Personally I would have looked and altering the stock chopper steering angle, and adding a bit of length to the swinging arm on a 348, before getting involved with very fiddly engineering work to alter the clutch.

07-29-2012, 02:02 PM	#320
Twin-shocker Studly Adventurer Joined: Jan 2012 Oddometer: 993	Thats strange...............looks a very simple job for anyone with a largish lathe, and some brass or bronze bar stock?

07-29-2012, 02:28 PM	#321
PSchrauber Studly Adventurer Joined: Jan 2011 Location: Summer: Kemiö, Finland; Winter: North Germany Oddometer: 641	Yes it looks easy but the rotor with the added weight needs to be balanced, which is impossible if you don't have a balancing machine.

07-29-2012, 10:26 PM	#325
Twin-shocker Studly Adventurer Joined: Jan 2012 Oddometer: 993	As a matter of interest how many times have you used your 348 in competition, and what leads you to thinking that a clutch conversion is needed on it?

07-30-2012, 04:02 AM	#327
Twin-shocker Studly Adventurer Joined: Jan 2012 Oddometer: 993	Why not fit a new cable and extend the operating arm, then try the bike in competition and see how it works out? I owned 348 and 349 Monts back in the day, and if I was riding one today altering the chopper steering, and getting the suspension working better would be things I would be thinking of doing.

07-30-2012, 01:20 PM	#329
Twin-shocker Studly Adventurer Joined: Jan 2012 Oddometer: 993	Very easy way to get a good clutch pull on older bike is to fit hydraulic clutch conversion intended for pit bike. Would probably need a longer hose, but they are very cheap and need no adjustment once fitted and set up properly.