Lightening my Tomos A3 Clutches

Here are some shot of my first attempt at lightened clutch shoes. This first set has shed about 20% of it's weight. About 2/3 of that was right next to the fulcrum, but the other 1/3 is from the end furthest away.

It took until sunset. Then I rushed the clutch swap, put it together in the dark and heard what sounded like teeth shearing. I'm gunna sort it out tomorrow. but for now, here are some pics. Anyone else trying this?

Re: Lightening my Tomos A3 Clutches

I'd rather have the full friction surface and just run high tension springs.

Re: Lightening my Tomos A3 Clutches

I've run green springs and ed's meduim and heavy SS springs. they were a big improvement, but I'm not satisfied. I've tried all kinds of oils too. I want it to rap out, drop, nearly max out, and shift.

Nothing I've tried has done in yet, so this is my next attempt

Re: Lightening my Tomos A3 Clutches

I would talk to steve on here about balancing the clutch hub also if you are going this far. Just be super smooth. Sound like you want a ktm conversion kit for the clutches. (edited)

Re: Lightening my Tomos A3 Clutches

i think it is critical to the functionality of these shoes that they make full contact across the face, if they are tipping as they engage it could let the pin go past the outer edge of the slots in the hub.

its a lot easier to just drill some holes in the meat behind where the springs run.

Re: Lightening my Tomos A3 Clutches

well, I pulled the springs out and reassembled the clutch to see where the shoes were contacting the bell and nothing i removed was touching. The pads are almost brand new so only the end of the shoe actually tuched the bell. I'm sure if they wore down a bit the whole shoe would contact. But if this happened, they're only going to get more grippy. I might lose life on the clutch, but by the time it goes, it's probably time to rebuild anyway.

Well, i just youtubed "tomos ktm", and ya, that sounds exactly like what I'm after. I don't see why we cant get it out of this clutch though.

Re: Lightening my Tomos A3 Clutches

read the tomos clutch pad material thread, there is tons of good info in there.

i've never built a crazy gear-eating ubertomos like matt in florida, but i did build a pretty agressive sprinter that launched really well using the asbestos-like friction material.

place i go to gets $15/clutch and they are literally indestructable

Re: Lightening my Tomos A3 Clutches

Graham Motzing Wrote:

-------------------------------------------------------

> read the tomos clutch pad material thread, there

> is tons of good info in there.

>

> i've never built a crazy gear-eating ubertomos

> like matt in florida, but i did build a pretty

> agressive sprinter that launched really well using

> the asbestos-like friction material.

i've read that thing at least 12 times. I wanted to get this grippy stock stuff to work while i've got it though.

> place i go to gets $15/clutch and they are

> literally indestructable

whats ^^this about?

Re: Lightening my Tomos A3 Clutches

not a Baron Asshole /

On an a35 the pads wear out only in the middle with the design. Its funny because many people think its an upgrade to use a3 shoes, and also lign the entire width.

Re: Lightening my Tomos A3 Clutches

The friction material on the A3s is thick, even if they only grip in the middle at the beginning they will wear until they are gripping with more then 50% of the pad at least. Hell before I blew my 1st gear it wore the entire shoe front to back. I had like 2-3 table spoons of aluminium powder in my fluid.

Re: Lightening my Tomos A3 Clutches

So here's a video of them installed. Once it warms up it's more consistent. I'm pretty happy with the results for now

Re: Lightening my Tomos A3 Clutches

damn I'm happy i have a technigas and not those shit speed pipes

Re: Lightening my Tomos A3 Clutches

Here's another shot from the outside.

First needs to get a little higher and then drop so I'm going to lighten it another 10-15%

Second engages at the right part, slips for a second building revs and then settles into a low slip. I'm going to angle the front of the pad a bit to push oil out of the bell and see if it hooks up better.

Re: Lightening my Tomos A3 Clutches

here's a speedo vid so you can hear the rpms and see speed as it accelerates. keep in mind its a 31/20 sprocket setup so i still reach 50 at pretty low rpm

Re: Lightening my Tomos A3 Clutches

nerdzilla No mo Peds no mo /

What's the rest of your setup? And please report back if/when they blow. I'm interested. I got alot of clutch shoes. Ed, make us some more springs. Maybe heavier even.

Re: Lightening my Tomos A3 Clutches

Airsal 70

Hi comp head

4 petal

Vm20

Mild porting

Biturbo

31/22 sprockets

I've opened the case a few times to check on things. No damage yet.

Re: Lightening my Tomos A3 Clutches

nerdzilla No mo Peds no mo /

With all the goods on there your best upgrades are a real chamber ( lots out there! From hack/weld cheap (alsil quich) to bolt on blast (mlm,mmm...) and an upgraded ignition. Even the cheapo 77 ignition lights up and burns better than the a35 ignition. I even had the ducati cdi box. I'd go pietcard.

Then you'll really get what your looking for out of that cylinder and carb.

Re: Lightening my Tomos A3 Clutches

All the ruined A3 clutches I've seen have been cracked near that pin, along the grain. I'd be too scared to even machine it, lest I worsen some already-existing stress fracture.

Also, replacement A3 clutches are becoming hard to find. Mopedjunkyard.com was the only one who had them last time I needed one.

Re: Lightening my Tomos A3 Clutches

400 miles on them now and still ripping..

Re: Lightening my Tomos A3 Clutches

GET REALIZED! BE HERE NOW! /

Re: Lightening my Tomos A3 Clutches

have you run those yet evan????

Re: Lightening my Tomos A3 Clutches

GET REALIZED! BE HERE NOW! /

yep probably 50 miles on them or so

been cold...

Re: Lightening my Tomos A3 Clutches

And?

Re: Lightening my Tomos A3 Clutches

nerdzilla No mo Peds no mo /

Damn Evan! If they dont explode those look like money! You should make a mold and have them cast!

Re: Lightening my Tomos A3 Clutches

GET REALIZED! BE HERE NOW! /

They haven't exploded. I don't ever go easy on them or anything, and I ride the dumb thing so I feel like they might last, bike revs way out before shifting like I think at 27x22 it probably does low 20's in first, next warm day I'll probably pull the side cover and see if they are still in one piece and check for cracks, I'd be willing to bet the pad material adhesion gives up the ghost before the actual shoes break.

That's first gear, I mean it engages higher than before it was lightened, I'm still looking for higher engagement, but I can't see where I would loose more material on the shoes, so I guess I'll wait for stiffer springs, or for some kind of ktm clutch setup to fall into my lap.I could also use a lighter flywheel.

I weigh 250lbs and I don't normally ride with a bunch of fast bikes or anything, but the only thing that is quicker of the line is my man mickrkittens' moby, but mick only weighs like a buck twenty or something.

Casting them would be funny, because all I did was eye ball them on a drill press.

if anyone wants to talk clutches or whatever, feel free to get at me.

Re: Lightening my Tomos A3 Clutches

nerdzilla No mo Peds no mo /

I had to get rid of my drill press when I moved out west or I'd probly go out and do the same to a set of mine.

Re: Lightening my Tomos A3 Clutches

Hit em with a hand drill or a dremil like mine. More than one way to skin that cat

Re: Lightening my Tomos A3 Clutches

nerdzilla No mo Peds no mo /

Yeah, but w a press you can be more accurate. Plus I have very limited free time....

Re: Lightening my Tomos A3 Clutches

BALTARD TERRODAKTYLREXXX EVAN Wrote:

-------------------------------------------------------

> Casting them would be funny, because all I did was

> eye ball them on a drill press.

>

> if anyone wants to talk clutches or whatever, feel

> free to get at me.

If this ever happened add a few (like I dunno 10) thou under the pin hole. And where ever else they crack.

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