Cush Drive Maintenance Update

[Greg Field]

I posted a thread a few years ago about how to really make and keep your cush drive functional. Almost always when I disassemble one, they are frozen in place and nonfuctional for rust and lack of grease. There are several levels to which you can take it:

 

The most basic is to pull it apart and grease it. If you do not do this, it will seize up and be non-functional. The one on my mutant Coppa Ductapio was in this state after maybe 12,000 miles (I did not write down the mileage but it was almost 2 years ago.)

 

The next level is to grease and drill out the rubbers so they are not so hard.

 

The right level, IME and IMO, is to take it all the way to the MATT (More Anal Than Thou) level, which means greasing it, removing half the pairs of pucks, and then drilling each puck to make it actually give and absorb shock. This is what I always do for my bikes and bikes in my care on which the owner wants to really be nice to his splines. It makes an enormous difference in cush-dirve action that you can feel, and it drastically reduces spline wear. See the earlier thread for pix of that.

 

After I got back from the National, I had to replace a roasted tire, so I though I's take the 5 minutes to open up the cush drive and see how it was holding up. Here's a pic of what I found:

 

 

The pucks were moist with grease and perfect and pliable. The cush bearing surface was just starting to show surface rust. It definitely was still operating, as shown by the shiny spots, but it was crying out in pain for grease. I knocked off the surface rust with a cloth and greased everything well.

 

Based on this, I'm going to grease it at every tire change, so at about every 7,000 miles on the Ballabio. If you haven't done yours in a while, or ever, I can garantee you it is running in pain, too.

[jrt]

Thanks for the update. Makes me feel better that I did mine several years ago.

I didn't remove half the pucks and drill though- I just put them back in. I doubt there is any difference in the result.

I find the incursion of rust rather interesting. You fellers get a lot of rain up there.

[Guest ratchethack]

You fellers get a lot of rain up there.

Aye. My cushies (as well as the drive plate forging and bearing collar) have all been as gushy with BTWBG (boat trailer wheel bearing grease), and no hint of the dreaded ferrous cancer, checking at EVERY OTHER tire change over the entire 5 year period since I first drilled and lubed 'em.

 

But o' course, that's just me. We get ~10" rainfall/year.

 

Seattle gets nearly 4X that -- AND on top o' that, nearly 10" snowfall.

[Bocephus]

Great timing for this; I performed this modification about 5 weeks ago and the difference was quite noticeable the first twist of the throttle. Better yet the compression braking shouldn't take such a toll now.

 

I was wondering at the time when a maintenance thread or update to the original would pop up as I was a bit apprehensive removing half the pucks and drilling (with utmost precision mind you) the remainder.

 

I have to give a hearty thanks to all you Gents who have made this site what it is. I have spent hours here reading and researching the trouble spots on my 2000 v11 and the wealth of knowledge is impressive.

[The Monkey]

Great timing for this; I performed this modification about 5 weeks ago and the difference was quite noticeable the first twist of the throttle. Better yet the compression braking shouldn't take such a toll now.

 

I was wondering at the time when a maintenance thread or update to the original would pop up as I was a bit apprehensive removing half the pucks and drilling (with utmost precision mind you) the remainder.

 

I have to give a hearty thanks to all you Gents who have made this site what it is. I have spent hours here reading and researching the trouble spots on my 2000 v11 and the wealth of knowledge is impressive.

 

 

No kidding, the sharpness of the learning curve has been greatly reduced thanks to their efforts. If I can add this to the Cush Drive thread. Use an impact driver to remove buttonheads intact (replace socket head end with a 1/2 to 3/8 adaptor impact type), put on 4mm 3/8 drive. Heat (propane) 10 seconds each all way round, half hearted strike on driver (each) 20 oz ballpeen, 5 second heat all now progressivelly harder hit round the circuit. Holding impact keep tension counterclockwise and weight directly down this basic advice is not commonly utitilized but is necessary in order to have success with this tool. All broke free, no damage to threads or the non-impact 4mm, nor the buttonhead! This works on your rotors and everywhere else those Mandallarians managed to tighten things past reason. One day I hope to see an Italian Allen Wrench as they apparently put ours to shame.

learni

[savagehenry]

I just put in socket head cap screws, no more buggerd buttonheads for me!

[guzzi jon]

Greg,

Will this make the short framed spineys wobble more? OC Johnnies wobbles like a mofo, he has to crank the steering damper down, and its been sorted,... some of them suckers just plain wobble

[Tom M]

I just put in socket head cap screws, no more buggerd buttonheads for me!

 

I assumed that they used button heads because there wasn't enough clearance for socket heads. Are you sure the socket heads aren't rubbing on the the adjacent part?

[Greg Field]

Greg,

Will this make the short framed spineys wobble more? OC Johnnies wobbles like a mofo, he has to crank the steering damper down, and its been sorted,... some of them suckers just plain wobble

 

Have a midget porn star perform an exorcism . . .

[savagehenry]

I assumed that they used button heads because there wasn't enough clearance for socket heads. Are you sure the socket (?) heads aren't rubbing on the the adjacent part?

I did this a few thousand miles ago. I didn't see where there would have been any clearence issues when I last serviced the pucks. I just put a new rear tire on only a couple hundred miles ago, and didn't see any evidence of problems at that point, but I didn't dissassemble the cush set up at that time. I kind of think the buttonheads were put there to dictate how much torque you could put on them, as the allen wrench would twist if you got all apeshit on over-tightening them. I trust myself more than that.

[The Monkey]

You would know instantly if the socket heads didn't clear. Just be sure to use a cad plate fastener as stainless will marry with the aluminium. If you do have stainless then coat the threads- grease, threadlock, antiseize, silicone, what have you and spin em out now and then and recoat em or you will have the threads destroyed due to the incompatability of aluminium and stainless. I agree with the philosophy though Henry. Harder, faster, if its shite then shitcan it,

hell it took a grade 8 bolt to maintain a license plate holder and tailight on the panhead. But I do enjoy the challenge in making the stock item actually do its job.

[savagehenry]

I agree with the philosophy though Henry. Harder, faster, if its shite then shitcan it,

hell it took a grade 8 bolt to maintain a license plate holder and tailight on the panhead. But I do enjoy the challenge in making the stock item actually do its job.

I'm beginning to see a bit of a trend here, for I too am beholdin' to the pan motor. A little pain makes for added pleasure, no?

[dlaing]

I am not going to argue here, but provide food for thought and just hint at one important FACT that each of you may take or leave on your own accord.

If you think this if over analyzing, fine. I expect that from the majority of the forum.

Think about how much force it takes to lift the front wheel off the ground.

Imagine putting a lever between the axle and one of those vanes and provide enough leverage to lift the front end.

Do you think the one vane might break?

What if you applied one third of that force?

Obviously Greg's and others' haven't broken, so we have evidence that it can probably handle one third of that force.

If you put a wedge of that rubber under torque, at what point do you think it would reach a point of no longer absorbing energy?

If you want to be scientific about it, should you weigh the front end, determine the wheelbase, determine the center of gravity, get an engineer to calculate the force for you? Or should we go with known typical dyno torque forces of 60-65 foot pounds of torque?

What is 65 foot pounds of torque and how could that possibly lift the front wheel off the ground?

What force is enough to break the fusion of rust?

Compare that wheelie poppin' force to the force of an aggressive downshift that causes the rear wheel to skid.

Are the forces during maximum acceleration and deceleration significantly different, so as to warrant different numbers of wedges for acceleration and deceleration?

What wears the splines more, the vibrating forces occurring as we drone the endless highways, or the on again off again throttling in the twisties, or the occasional maximum force in either direction?

Like spring firmness on a motorcycle's suspension, there is an ideal and there are compromises.

Do you think a silicone grease might work best with rubber wedges?

Now engineer your drilling and puck removal or lack there of, targeting that ideal.

Your splines will thank your uncommonly good reasoning.

Best of luck.

[The Monkey]

I'm beginning to see a bit of a trend here, for I too am beholdin' to the pan motor. A little pain makes for added pleasure, no?

 

That is so true, I consider it a reason for being on this endlessly entertaining orb. If you dont have to work for it,

where can the basis for appreciation lie? Hence the yawn factor on turn key machinery and strippers. Cheers man!

[sullvarni]

I posted a thread a few years ago about how to really make and keep your cush drive functional. Almost always when I disassemble one, they are frozen in place and nonfuctional for rust and lack of grease. There are several levels to which you can take it:

 

The most basic is to pull it apart and grease it. If you do not do this, it will seize up and be non-functional. The one on my mutant Coppa Ductapio was in this state after maybe 12,000 miles (I did not write down the mileage but it was almost 2 years ago.)

 

The next level is to grease and drill out the rubbers so they are not so hard.

 

The right level, IME and IMO, is to take it all the way to the MATT (More Anal Than Thou) level, which means greasing it, removing half the pairs of pucks, and then drilling each puck to make it actually give and absorb shock. This is what I always do for my bikes and bikes in my care on which the owner wants to really be nice to his splines. It makes an enormous difference in cush-dirve action that you can feel, and it drastically reduces spline wear. See the earlier thread for pix of that.

 

After I got back from the National, I had to replace a roasted tire, so I though I's take the 5 minutes to open up the cush drive and see how it was holding up. Here's a pic of what I found:

 

 

The pucks were moist with grease and perfect and pliable. The cush bearing surface was just starting to show surface rust. It definitely was still operating, as shown by the shiny spots, but it was crying out in pain for grease. I knocked off the surface rust with a cloth and greased everything well.

 

Based on this, I'm going to grease it at every tire change, so at about every 7,000 miles on the Ballabio. If you haven't done yours in a while, or ever, I can garantee you it is running in pain, too.

I'm fairly new to Guzzis so am still trying to find my way around,i have this weird sound that seems to be coming from the rear of the bike at low speeds,coming to intersections,parking lots,and so forth.

Can't seem to nail it down,it's not constant but very noticeable when it appears,does'nt seem to efect the running of the bike at highway speeds.

 

I replaced the two rear wheel bearings last year on a ride,was warned about there frail'ty and it came to pass not two months after i purchased the bike.

So what i want to know is could this sound i'm hearing have anything to do with the cush drive,it looks like there's another bearing in there is this correct?

 

I'm a bit out in the boonies in Northern British Columbia Canada so dont' have the Guzzi expertise near by,my local Garu's

were'nt much help,good guys but not used to dealing with Italian moto bicycletta's,apolo'gys for the ramble i'll go now.

 

Thanks Stu.