Rear drive question

[bigbikerrick]

Yesterday I took the rear wheel off the v 11 to grease the splines, and noticed that the "rod" that attatches to the top of the rear box ,at the top attatchment point doesnt move freely, I loosened the bolt and the rubber/metal joint is very stiff, I thought the rear drive would swing easily at that joint, but it is very tight, the only give when the swingarm arcs up and down with suspension travel is from the rubber "bushing " flexing. I realize this "rod" is meant to prevent jacking on the suspension under acceleration/deceleration, but is this joint supposed to be real tight? ,almost un-moveable? should that bolt be greased?I havent put things back together until I hear from the experts here. Thanks.

[docc]

Yeah, the 'reaction rod' is firmly mounted. All the movement is torsion in the rubber bushings. Which explains why they eat up after a while. I t would be worse to find the bushings trashed and the rod loose ( Always a good thing to inspect).

 

You've got to think it creates kind of a torsion bar effect on the rear suspension action.

 

Andy fitted a free rotating Delrin (sp?) bushing to his '02 LeMans for a long term test. Maybe he'll let us know how it turned out?

[Guest ratchethack]

Like Docc said. The amount of torque it generates is infinitessimally small when you consider the length of the torque arm, as designed. You can probably overcome it over the full travel of the hub with your little finger. Not to worry.

[bigbikerrick]

Yeah, the 'reaction rod' is firmly mounted. All the movement is torsion in the rubber bushings. Which explains why they eat up after a while. I t would be worse to find the bushings trashed and the rod loose ( Always a good thing to inspect).

 

You've got to think it creates kind of a torsion bar effect on the rear suspension action.

 

Andy fitted a free rotating Delrin (sp?) bushing to his '02 LeMans for a long term test. Maybe he'll let us know how it turned out?

69999[/snapback]

Thanks Docc,just wanted to make sure it wasnt another thing Luigi forgot to grease up at Mandello! LOL.

[bigbikerrick]

Like Docc said.  The amount of torque it generates is infinitessimally small when you consider the length of the torque arm, as designed.  You can probably overcome it over the full travel of the hub with your little finger.  Not to worry.

70012[/snapback]

Thank you, Sir. I will sleep much better today!

[docc]

I was hoping Andy would chime in on how his freed up the suspension action and how he can make them available in bulk for medium-cheap.

 

It sure seems to me the travel would be less impeded if the bushing rotated freely.

 

Andy?

[guzzi323]

You could get one of these from Rossopuro..

http://rmcube.abd.it/RMcube/servlet/contro...deObject=MT1030

 

It replaces the torque arm with one which has heim joints at either end. I got tired of the rubber failing on mine so I made one with big heim joints and a fat threaded aluminum shaft which I got from McMaster Carr. I did have to get some bushings machined to make up the difference between the i.d. of my heim joints and the o.d. of the mounting bolts.

It looks to me like this premade one from Rossopuro might be the way to go.

 

johnk

[Bbennett]

I have this item from Rossopuro and like it - installations was easy as cuold be too

[Alex-Corsa]

Since the subject is about that thingie here, a question is,

Is it true that if ones changes the back suspencion (i,e, make the bar longer)in order to increase height this arm should also change length?

[bigbikerrick]

You could get one of these from Rossopuro..

http://rmcube.abd.it/RMcube/servlet/contro...deObject=MT1030

 

It replaces the torque arm with one which has heim joints at either end. I got tired of the rubber failing on mine so I made one with big heim joints and a fat threaded aluminum shaft which I got from McMaster Carr. I did have to get some bushings machined to make up the difference between the i.d. of my heim joints and the o.d. of the mounting bolts.

It looks to me like this premade one from Rossopuro might be the way to go.

 

johnk

70128[/snapback]

Did you add heim joints to your existing shaft, or replace the whole thing? Do you have a picture you can post? This is prolly a good project for the "how to section"

[guzzi323]

Did you add heim joints to your existing shaft, or replace the whole thing? Do you have a picture you can post? This is prolly a good project for the "how to section"

70207[/snapback]

I don't have any pics, but what I ended up with is a big ugly version of the sculpted looking pretty piece that Rossopuro sells. Nothing of the original piece is used. McmasterCarr sells big heim joints and threaded aluminum rod (I think it was 5/8" diameter.)

I started out ordering the heim joint to the correct size for the mounting bolts but then the mating rod diameter seemed thin so I went for a thicker rod and had the bushing made for the bolts.

Next time I've got the bike on the stand I'll take some pics and see if I can reconstruct the process I did. If I recall the parts were much less expensive than any replacement bit.

 

I just poked around www.mcmaster.com and I think these are what I used.

 

6072K223 Ball joints $12.79 each

6516K43 Threaded rod 24" long $13.75 each

You'll also need a couple of jamnuts.

 

I'm not certain of the length, pull yours off and measure it. Your results may vary. I'm not responsible, always work with a qualified mechanic, etc. but that's basically what I did. It's been at least 15k miles and the bronze bushings in the joints are just showing a little bit of slop in them. If you want I think they sell ones with zerk fittings as well.

 

johnk

[bigbikerrick]

I don't have any pics, but what I ended up with is a big ugly version of the sculpted looking pretty piece that Rossopuro sells. Nothing of the original piece is used. McmasterCarr sells big heim joints and threaded aluminum rod (I think it was 5/8" diameter.)

I started out ordering the heim joint to the correct size for the mounting bolts but then the mating rod diameter seemed thin so I went for a thicker rod and had the bushing made for the bolts.

Next time I've got the bike on the stand I'll take some pics and see if I can reconstruct the process I did. If I recall the parts were much less expensive than any replacement bit.

 

I just poked around www.mcmaster.com and I think these are what I used.

 

6072K223 Ball joints $12.79 each

6516K43  Threaded rod 24" long $13.75 each

You'll also need a couple of jamnuts.

 

I'm not certain of the length, pull yours off and measure it. Your results may vary. I'm not responsible, always work with a qualified mechanic, etc. but that's basically what I did. It's been at least 15k miles and the bronze bushings in the joints are just showing a little bit of slop in them. If you want I think they sell ones with zerk fittings as well.

 

johnk

70236[/snapback]

Thank you Sir, I wonder if heim joints can be installed in the stock moto guzzi rod???

[docc]

The Guzzi rod looks like a cast piece. Doesn't look like anyplace to screw in a Heim joint.

 

So, John, do you think the suspension is more compliant with the Heim joints? As in, do you think the stock rubber bushings impede movement in the travel?

[guzzi323]

So, John, do you think the suspension is more compliant with the Heim joints? As in, do you think the stock rubber bushings impede movement in the travel?

70294[/snapback]

All I know is I felt no difference. In theory, there'd be some kind of difference but you might need all those high-tech sensors and data aquisition stuff the motoGP guys have to tell the difference.

I was replacing it because I went though 2 of the stock arms with deteriorating bushings in under 20k miles. If I recall, the dealer wanted $174.00 for one.

johnk