Clutch for LM III - Which Way to Go

[jksymz75]

I'm going to install the 4mm Spline Hub In my '83 LM III and will refresh my clutch while I'm there.

The question is:

Do I keep It stock with the Stein Dense Kit? If I do, can I get away with resurfacing the flywheel or should I replace?

Do I step up to the RAM Low Inertia Kit? Any experiences with this set up?

https://www.mgcycle.com/index.php?main_page=product_info&products_id=1698:9fe97fff97f08966113 5d0487843108e


I ride street only and usually pretty spirited. Bike is stock except pods and jetting.

Thanks In advance

[guzzisteve]

I've been putting in these------------------------------------

https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4766

If you are going w/deep splines, it's a stronger disc.
 
I do a cross hatch with 80 or 60 grit on contact surface if it's not worn in and all flat on mating surface.

I have been using cindered bronze surflex plates for the last 35K mi. There were no deep splines in 85 when I put them in and they were lighter by 1/2lb. I pulled it apart in 07 after a total wreck and wow the surfaces are way worn in. They might go back in w/my 7lb flywheel, haven't decided. The steel wore more than the plates. I do have another set of 3 cindered that are for racing, just like the 2 I been using just thinner w/2 intermediate plates 

[jksymz75]

I've been putting in these------------------------------------

https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4766

If you are going w/deep splines, it's a stronger disc.
 
I do a cross hatch with 80 or 60 grit on contact surface if it's not worn in and all flat on mating surface.

I have been using cindered bronze surflex plates for the last 35K mi. There were no deep splines in 85 when I put them in and they were lighter by 1/2lb. I pulled it apart in 07 after a total wreck and wow the surfaces are way worn in. They might go back in w/my 7lb flywheel, haven't decided. The steel wore more than the plates. I do have another set of 3 cindered that are for racing, just like the 2 I been using just thinner w/2 intermediate plates 

Thanks for the insight. You're saying you create a crosshatch on flywheel?

That's the other kit I was thinking of going with. I've read about others' experience with lightened flywheels and there's some positive aspects, I just don't want to change the character of the bike for worse.

[Furbo]

Thanks for the insight. You're saying you create a crosshatch on flywheel?

That's the other kit I was thinking of going with. I've read about others' experience with lightened flywheels and there's some positive aspects, I just don't want to change the character of the bike for worse.

Guzzi Steve gave great advice. Flywheel - leave it be. The LM III is never be fast again (unless there's an apocalypse and you've still got your kettering ignition). It will rev a bit quicker but will likely vibrate more and idle rougher.

[moto-uno]

  My experience with the lightened flywheel ( by Charlie Rice)  was an even smoother running bike and there was no negative effect on
the idling . The flywheel assembly was balanced at the time . I too ran the Sureflex sintered bronze plates in my Le Mans 2 for
almost 100k kilometers and I really enjoyed it . BUT , as was mentioned , it sure grooved the flywheel ( as they had a smaller
friction surface) . By that time the flywheel had become quite grooved . Luckily I had access to an amazing machinist and he made a broach
to repair the flywheel grooves and machined the friction surface flat again . 25 years and over another 150k kilometers on
it and it's working fine with the 4mm deep spline and Stein Dense clutch plate kit . My experience with the RAM clutch absolutely sucked .
Nice and light with great throttle response , but the earlier ones were crap , plate was shot in only 500 kilometer ( yeah , 350 miles) .
They sent another and it lasted almost 800 kilometers before I had to pull it again . 4 or 5 variations later they apparently have cured it.
I took my 2nd plate into a truck shop and the fellow that ran the brake and clutch shop machined down some friction material he had to the
correct 8mm width ( he looked at it like it was jewelry compared to what he worked on ) and it too now works a treat in my other goose.
YMMV :) Peter

[Antietam Classic Cycle]

I'm going to install the 4mm Spline Hub In my '83 LM III and will refresh my clutch while I'm there.

The question is:

Do I keep It stock with the Stein Dense Kit? If I do, can I get away with resurfacing the flywheel or should I replace?

Do I step up to the RAM Low Inertia Kit? Any experiences with this set up?

https://www.mgcycle.com/index.php?main_page=product_info&products_id=1698:9fe97fff97f08966113 5d0487843108e


I ride street only and usually pretty spirited. Bike is stock except pods and jetting.

Thanks In advance

There is no surface on the flywheel itself to resurface, only splines that can wear. The surface that the friction plates contact are on the pressure plate, intermediate plate and ring gear/clutch cover plate. The SD-TEC clutch kit comes with the intermediate plate (as well as the 4 mm hub): https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4766 , so that only leaves the pressure plate and cover plate.

Most often the pressure plate and cover plate need only the "glaze" removed from them. I use an an abrasive pad in my angle die grinder to do that.

The SD-TEC friction plates are slightly thicker than the originals, so you may need a slightly longer clutch pushrod or to just add an extra throw-out bearing thrust washer in order for it to release properly.

Probably best to replace the throw-out bearing and I find this double o-ring outer body helpful in preventing leaks: https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4793

I'd recommend replacing the clutch pushrod seal(s) as well. Guzzi used two conical rubber seals which I've had leak. I use a stack of six o-rings instead and will send you some for free (assuming that you're in the US).   

[jksymz75]

The lightness at the lever is a big selling point for me, as well as the quicker revving.

[jhem68]

Jksymz75, your last comment sounds like you want someone to convince you to go with a RAM clutch set up. That's what I put in my Eldo last year after installing the SD Tech clutches in my 850T and SP1000 in the previous years.

If lightness at the lever as well as the quicker revving are strong selling points for you, it is the  better option. I have arthritis in my hands and have experimented with 3 different hydraulic set ups on early Tonti's
with varying success, but none are an easier pull than the RAM set up. I can't speak to the longevity of the  newer RAM clutch, but I experience none of the other issues that sometimes require adjustments other than installing the slightly longer clutch pushrod that MG Cycle carries.

Nothing wrong with the SD Tech set up and if you go that route follow the advice from Charlie and you simply can't go wrong although I would add to it by suggesting a reminder to be sure and clean the intermediate plate with a solvent before installation.

[jksymz75]

There is no surface on the flywheel itself to resurface, only splines that can wear. The surface that the friction plates contact are on the pressure plate, intermediate plate and ring gear/clutch cover plate. The SD-TEC clutch kit comes with the intermediate plate (as well as the 4 mm hub): https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4766 , so that only leaves the pressure plate and cover plate.

Most often the pressure plate and cover plate need only the "glaze" removed from them. I use an an abrasive pad in my angle die grinder to do that.

The SD-TEC friction plates are slightly thicker than the originals, so you may need a slightly longer clutch pushrod or to just add an extra throw-out bearing thrust washer in order for it to release properly.

Probably best to replace the throw-out bearing and I find this double o-ring outer body helpful in preventing leaks: https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=4793

I'd recommend replacing the clutch pushrod seal(s) as well. Guzzi used two conical rubber seals which I've had leak. I use a stack of six o-rings instead and will send you some for free (assuming that you're in the US).   

Thanks for all this great info and the offer of the o-rings. If I go this route, I'll send you a PM and take you up on the offer. I especially appreciate the insight into the longer clutch push rod (the 250mm one, right?), the advice about replacing the throw-out bearing and using the outer body with the double o-rings. Pure gold.

Jksymz75, your last comment sounds like you want someone to convince you to go with a RAM clutch set up. That's what I put in my Eldo last year after installing the SD Tech clutches in my 850T and SP1000 in the previous years.

If lightness at the lever as well as the quicker revving are strong selling points for you, it is the  better option. I have arthritis in my hands and have experimented with 3 different hydraulic set ups on early Tonti's
with varying success, but none are an easier pull than the RAM set up. I can't speak to the longevity of the  newer RAM clutch, but I experience none of the other issues that sometimes require adjustments other than installing the slightly longer clutch pushrod that MG Cycle carries.

Nothing wrong with the SD Tech set up and if you go that route follow the advice from Charlie and you simply can't go wrong although I would add to it by suggesting a reminder to be sure and clean the intermediate plate with a solvent before installation.

Thanks for sharing your real-world assessment of the RAM clutch. I've been having problems with my arms (tennis elbow) so less strain is a good thing for me, as well.

I have to admit that it's appealing to me but I'm in the midst of spending a lot of $$$ on a Ducati rebuild as well as various other projects so money is a factor. I've had my LM III for 10 years now so doing something that might wake up the performance a little bit as well as ease of installation is pretty hard to resist, though.

[Stevex]

Lightened flywheel and ring gear on my LM2, rebuilt with standard clutch plates and deep spline hub about 7 years ago now.
It runs and idles great and the lightened flywheel / ring gear for me makes a more responsive engine compared with the oem flywheel lump.
By cindered I'm guessing that should be sintered?
Have you considered replacing the gearbox's input and output seals for Viton items since you have the box on the bench?

[jksymz75]

Lightened flywheel and ring gear on my LM2, rebuilt with standard clutch plates and deep spline hub about 7 years ago now.
It runs and idles great and the lightened flywheel / ring gear for me makes a more responsive engine compared with the oem flywheel lump.
By cindered I'm guessing that should be sintered?
Have you considered replacing the gearbox's input and output seals for Viton items since you have the box on the bench?

Thanks for chiming in Steve, I was reading your response to a similar thread in '15 about this subject and it was one of the major points in the "pro" column. Someone else made the comment about cindered/sintered so I'll leave that to them, but did you have your flywheel lightened by a machine shop or did you spring for a kit/do an exchange?

I was planning to order the "SUPPLEMENTAL CLUTCH INSTALLATION KIT" from MG Cycle and it includes the Viton input shaft seal. 

[guzzista]

As someone with both a ST Tec clutch with a Lemans standard  flywheel and  a Ram clutch currently in  operation, I second every comment on the SDTec as a first choice. Lightening of the flywheel is an option but not necessary IMO based on having run 2 Tontis with lightened flywheels in the past, albeit both on street ridden bikes . As for the RAM, I am running a late style friction disc, which was redesigned and made thicker than the earlier ones.
It requires attention to keep an eye on  the correct freeplay in order as not to cause unwanted wear. The light feel at the lever and ease of shifting are noticeable. The bike only gets used as a fun backroad ride, so it works for me, but if traffic and or touring work is  the norm, I could not recommend it, especially for the "Guzzi Content" part AKA the cost. MG Cycle does sell a mixed clutch spring set to make the action lighter and Guzziology does have a bit on adjusting the  clutch for more gradual engagement (or is it disengagement?).  For scuffing friction areas I use this:
https://www.amazon.com/Brush-Research-Flex-Hone-Rotors-Medium/dp/B007INTE3Q
https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=5335

[John A]

Maybe the newer Ram clutch friction plates last longer than previous ones which were good for maybe 10K miles on the road. Otherwise plan on replacing at that interval. Snot a big deal on track bikes that get looked at more often than a road bike but I quit using them because of the longevity issue. The best I ever got out of a Ram was 15K by spacing the lever perch farther away from the bar, enabling more throw so I could get free play and have it release cleanly

[jksymz75]

As someone with both a ST Tec clutch with a Lemans standard  flywheel and  a Ram clutch currently in  operation, I second every comment on the SDTec as a first choice. Lightening of the flywheel is an option but not necessary IMO based on having run 2 Tontis with lightened flywheels in the past, albeit both on street ridden bikes . As for the RAM, I am running a late style friction disc, which was redesigned and made thicker than the earlier ones.
It requires attention to keep an eye on  the correct freeplay in order as not to cause unwanted wear. The light feel at the lever and ease of shifting are noticeable. The bike only gets used as a fun backroad ride, so it works for me, but if traffic and or touring work is  the norm, I could not recommend it, especially for the "Guzzi Content" part AKA the cost. MG Cycle does sell a mixed clutch spring set to make the action lighter and Guzziology does have a bit on adjusting the  clutch for more gradual engagement (or is it disengagement?).  For scuffing friction areas I use this:
https://www.amazon.com/Brush-Research-Flex-Hone-Rotors-Medium/dp/B007INTE3Q
https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=5335

As much time as I've spent on the MG Cycle website in the past 3 days I never saw that set of lighter springs. Thanks for the feedback and the tips.

[jksymz75]

Just wanted to let everyone who was good enough to contribute know I went with the S-D kit and feel good about it.

[Stevex]

Thanks for chiming in Steve, I was reading your response to a similar thread in '15 about this subject and it was one of the major points in the "pro" column. Someone else made the comment about cindered/sintered so I'll leave that to them, but did you have your flywheel lightened by a machine shop or did you spring for a kit/do an exchange?

I was planning to order the "SUPPLEMENTAL CLUTCH INSTALLATION KIT" from MG Cycle and it includes the Viton input shaft seal.

My lightened flywheel / ring gear was an exchange with HMB-Guzzi in Germany.

[moto-uno]

   Thanks for the correction 'Charlie' , I was remembering completely backwards  .
   The crazy thing is I have an entire flywheel , ring gear , etc ,just down stairs  . Peter

[Frenchfrog]

As much time as I've spent on the MG Cycle website in the past 3 days I never saw that set of lighter springs. Thanks for the feedback and the tips.

Here you go

https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=5335

[Antietam Classic Cycle]

Here you go

https://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=5335

Except they aren't "lighter" in my experience! I tested them against original (used) springs) and found them to be significantly "heavier".

[jksymz75]

Except they aren't "lighter" in my experience! I tested them against original (used) springs) and found them to be significantly "heavier".

Is it common practice to re-use springs? Do they really wear out? Even though I’d appreciate a lighter touch, I didn’t mind the way it’s been. Also, I wonder if there’s some kind of a break in period after which they’d loosen up.

[Antietam Classic Cycle]

Is it common practice to re-use springs? Do they really wear out? Even though I’d appreciate a lighter touch, I didn’t mind the way it’s been. Also, I wonder if there’s some kind of a break in period after which they’d loosen up.

If the original springs are within the specs. in the shop manual, I reuse them.

[Frenchfrog]

When I rebuilt my beast about three years ago I changed the clutch springs simply because they were 40 or so years old  and also the clutch perch. I used springs from Stein Dinse and a Centuro perch with an adjustable span lever. The result is a very significantly lighter clutch than previously. I don't know why but assume that the springs might be lighter and or the perch/lever combination has a better leverage ratio.

[Matt Story]

So I have my clutch rebuilt on the bench with the SD Tech clutches, new intermediate plates and good condition (unworn, smooth) pressure plate and flywheel and original strength springs.  I am highly confident everything is aligned correctly, springs properly seated etc.  I would like to apply lighter springs, but I am surprised how easily the clutch slips on the bench with the standard springs.  Is this ease to slip normal?  Should I hatch my pressure surfaces or something?

[jhem68]

Matt,
Did you clean the intermediate plate with a solvent before you installed the kit? See the note on this itemhttps://www.mgcycle.com/index.php?main_page=product_info&cPath=193&products_id=220:


I don't think that that info is provided in the SD Tech kit notes.

[Matt Story]

Yes sir.  Everything is cleaned 'excessive compulsively' before reassembly

[John A]

It’s not normal.