Centauro/Daytona/1100 Sporti Throttle body sync rod

[Turin]

The plastic white adjustment star/knob broke on my bike. Damned if I can find a part number or a detail on any diagram.

anyone have any ideas?

[lucky phil]

The plastic white adjustment star/knob broke on my bike. Damned if I can find a part number or a detail on any diagram.

anyone have any ideas?

Most of the t/b parts are not available as separate Guzzi parts hence the use of Mercedes throttle linkage ball joint on the r/h t/b. Weber throttle bodies in the manufacturers eyes and Guzzi as well is it's not a service part, ie it's disposable and replaced as an assembly. I've bought Ducati t/bs when I've seen them going cheap and use them for spares as a lot of the stuff is common to Guzzi t/b's and ducati ones are cheaply available. Maybe you can search the internet for a substitute or find second hand throttle bodies for spares. I've been in the same situation when I rebuild them with new throttle shaft bushes and seals. I researched the original bush part numbers on an old bush and found the correct DU bushes and finally found Yamaha seals from a particular model fit. Other stuff such as what you need is problematical and there is no easy answer. Maybe someone could scan one create a file and print a replica? I'd be interested in one or two if somebody did.

Ciao   

[Chuck in Indiana]

Not having one to look at any more  I would think it would be easy enough to make. (?) Isn't it just a threaded knob?

[Joliet Jim]

Not having one to look at any more  I would think it would be easy enough to make. (?) Isn't it just a threaded knob?

I tried to look at it, but without taking it apart it's really hard to tell. Mine has also been impossible to turn since I bought it, but it was well balanced unlike it's owner.


Chuck if you ever want to take the chicken for a ride, you are welcome to. Of course you're also welcome to change the belts on it at the same time. 

[RinkRat II]

       This is the style on my 2000 sport, If you want I'll measure it out for you if it's the same.

     Paul B

[Turin]

here's a pic on another bike. mine is safety wired in place for now. the little fingers that snap into the hole have worn and now it falls out of place.

[Joliet Jim]

here's a pic on another bike. mine is safety wired in place for now. the little fingers that snap into the hole have worn and now it falls out of place.

Mine looks like this one

[pressureangle]

The knob on my '97 Sport looks like Turin and Joliet's.

If I was stuck, It appears there's enough thread to get a nut on either side of the post. With time to diddle I'd see about making an aluminum thumbwheel that sleeved the inside of the post; that might require a locking nut of some sort on the other side, or a very precise compression as with the plastic.
We have a CNC metal shop, and also machine plastic parts; we are in the exploration phase of adding 3d plastics but not there yet. I'd think that any kid with a basement set who can even marginally run AutoCAD could make this knob in plastic- the question is, 'what kind of plastic?'

Alternatively, you could make one simply enough with even a small benchtop lathe and common hand tools...if you had the right piece of plastic.
If anyone wants to give it a shot, I'll send you some plastic scraps to work with. If anyone has sample knobs I'll see if I can get the boys to make a few in the near term.

[lucky phil]

The knob on my '97 Sport looks like Turin and Joliet's.

If I was stuck, It appears there's enough thread to get a nut on either side of the post. With time to diddle I'd see about making an aluminum thumbwheel that sleeved the inside of the post; that might require a locking nut of some sort on the other side, or a very precise compression as with the plastic.
We have a CNC metal shop, and also machine plastic parts; we are in the exploration phase of adding 3d plastics but not there yet. I'd think that any kid with a basement set who can even marginally run AutoCAD could make this knob in plastic- the question is, 'what kind of plastic?'

Alternatively, you could make one simply enough with even a small benchtop lathe and common hand tools...if you had the right piece of plastic.
If anyone wants to give it a shot, I'll send you some plastic scraps to work with. If anyone has sample knobs I'll see if I can get the boys to make a few in the near term.

Delrin would be the material of choice. It's not a terribly simple piece this knob with it's split flange on one end that engages with the TB pivot fitting. Machinable on the lathe for sure but the splitting of the flange/bush end might be tricky and thats important. It might need a modification to the design for a home made product. I'd need to give it some thought.   

[Turin]

It's not a great design.

[lucky phil]

It's not a great design.

It's actually a good design just tricky to replicate in the home workshop. Unscrew the rod and the split spigot can be squeezed to remove from the pivot fitting. These things are pushing 30 years old now, not bad for a plastic part subject to engine heat, vibration and fuel occasionally.   
Be nice if Weber supplied some parts for these t/b's
Ciao

[pressureangle]

So yes, I'm going to make these available. Please Stand By.

[Turin]

 

[RinkRat II]

  Bumpity bump bump.........

     Paul B 

[Wayne Orwig]

That would be pretty easy to draft and print in my printer. But then, the plastics I can print would not like the heat.

[pressureangle]

That would be pretty easy to draft and print in my printer. But then, the plastics I can print would not like the heat.

Wayne,

If you have your own grinder and filament maker, I can send you some plastic scraps. If not, and you'd like to make the program, my kid has everything to make filament and print but can't yet program prototypes.
I sent my own throttle rod off to Ohio and we're in the preparations for machining these from hard stock.

[Turin]

 

[Chuck in Indiana]

I'm sure Austin could model and print those, but I don't know if he wants the job. He's pretty busy..

[pressureangle]

Pictures for the curious. The split retainer portion of the knob is not threaded; the assumption is that they snap on the post after the knob is threaded to the rod. Discussion decided it's better to leave it as the Italians did- it's easier to manufacture if you thread it all the way through, but considered the possibility that the thread friction would eventually stress and break the tabs. <shrug> I've lost every bet redesigning Italian engineering so far.

[Wayne Orwig]

The split retainer portion of the knob is not threaded; the assumption is that they snap on the post after the knob is threaded to the rod.

Not sure I follow.

I thought the tabs were pressed into the metal post first, then when threaded onto the rod, that 'locked' the tabs outward so they could not release.
But I no longer have a spine frame bike to look at closely.

[pressureangle]

Not sure I follow.

I thought the tabs were pressed into the metal post first, then when threaded onto the rod, that 'locked' the tabs outward so they could not release.
But I no longer have a spine frame bike to look at closely.

That's possible. We can't know. I'm not yet sure it's possible to thread the rod in first, but either way they saw fit not to thread the tabs. It's possible that since the part was cast rather than machined, they just left the threads out from under the tabs. I can only speculate. Even so, the taps may press the tops of the threads without actually being threaded. Careful measurement to follow.

[AZach]

I'm sure Austin could model and print those, but I don't know if he wants the job. He's pretty busy..

If I had one on hand I could probably model it up pretty easy. Been spending my little bit "free" time right now in the evenings modeling Guzzi parts. I got the rear main seal modeled and the light holder for the lemans 4 dash. Working on perfecting the light holder to print the best, right now is just modeled exactly like the original. I'll be adding material here and there to favor printing.
But yeah I have the capabilities of printing with some pretty nasty material and if time isn't super critical I wouldn't mind taking a stab at it if I can get a part in hand to model after? If I can't end up printing I'm sure I could take it to work and machine a few out of delrin. Anyone interested that has a part they can send hit me up! Love working on stuff like this.







since there's no help

[guzziart]

Depending on your level of desparation, there are these...they look to me like the same adjuster (like on my V11 Lemans) but could very well be in the same condition as yours.

https://www.ebay.com/itm/362925598507?fits=Make%3AMoto+Guzzi&hash=item54800d272b:g:GOQAAOSwhcZeVMJT

https://www.ebay.com/itm/313125853975?fits=Make%3AMoto+Guzzi&hash=item48e7c15b17:g:X7cAAOSwPq1e87WD

https://www.ebay.com/itm/324479772707?hash=item4b8c806823:g:pRQAAOSw3e9gIZBH

Art

PS - I think my 03 V11 Lemans has the same adjuster

[Wayne Orwig]

It's not a great design.

Wait, is the rod PULLING the plastic adjuster OUT of the block?
I think you need to put the adjuster on afterwards so that it is pulled INTO the block. Maybe loosen the rod on the opposite side to get more rod length.

Maybe.

Just a thought. As I said, I have not had my spine frame in years to look at.

[RinkRat II]

  Hi Wayne, I believethe setup on the Sport i actually pushes against the adjuster and on the spine frame  it  pulls aginst the adjuster. Correct me if I'm wrong Turin.
     Note the rod threads into the adjusters 180 degrees differently.

        Paul B 

[pressureangle]

If I had one on hand I could probably model it up pretty easy. Been spending my little bit "free" time right now in the evenings modeling Guzzi parts. I got the rear main seal modeled and the light holder for the lemans 4 dash. Working on perfecting the light holder to print the best, right now is just modeled exactly like the original. I'll be adding material here and there to favor printing.
But yeah I have the capabilities of printing with some pretty nasty material and if time isn't super critical I wouldn't mind taking a stab at it if I can get a part in hand to model after? If I can't end up printing I'm sure I could take it to work and machine a few out of delrin. Anyone interested that has a part they can send hit me up! Love working on stuff like this.







since there's no help

When mine's finished at the shop and I have a serviceable part in hand, I'll send the original over (or the dimensions/file) if someone hasn't already.

[Wayne Orwig]

  Hi Wayne, I believethe setup on the Sport i actually pushes against the adjuster and on the spine frame  it  pulls aginst the adjuster. Correct me if I'm wrong Turin.
     Note the rod threads into the adjusters 180 degrees differently.

        Paul B 

Can you get a photo?

I thought the Sporti had the same setup.

[pressureangle]

Can you get a photo?

I thought the Sporti had the same setup.

Pictures are upthread. It appears that the Sport-i (mine) has the fingerwheel inside the throttle post, where the V11s have the fingerwheel outboard where it's easier to access, and probably with a little longer rod. They appear to be the same knob.

[RinkRat II]

Wait, is the rod PULLING the plastic adjuster OUT of the block?
I think you need to put the adjuster on afterwards so that it is pulled INTO the block. Maybe loosen the rod on the opposite side to get more rod length.
   


  This is the orientation on the Sport i^^^^^^^^^^^^^^^^



   This is the orientation on the Spine frame^^^^^^^^^^^^
  The threaded rod enters the adjuster knob from opposite sides even though the metal block and the plastic adjuster are the same pieces.
 
      Paul B

[Wayne Orwig]

Wait, is the rod PULLING the plastic adjuster OUT of the block?
I think you need to put the adjuster on afterwards so that it is pulled INTO the block. Maybe loosen the rod on the opposite side to get more rod length.
   


  This is the orientation on the Sport i^^^^^^^^^^^^^^^^



   This is the orientation on the Spine frame^^^^^^^^^^^^
  The threaded rod enters the adjuster knob from opposite sides even though the metal block and the plastic adjuster are the same pieces.
 
      Paul B

Bizarre.

Can the rod be unscrewed a good bit on the opposite end, and the knob end reversed for strength?