Drive Gear Spinning

[Antonio]

2004 Ballabio with close to 40K. 

Pretty sure this is not supposed to do this. I thought it was the clutch at first, but the driveshaft turns while in gear but the rear wheel doesn't.

I pulled my rear box off and found the 32 bevel gear spins on its axis. Did I shear a key? Has anyone seen this before?

I don't drag race all the time...

I haven' been able to find the part. I may buy a complete assembly and rebuild. 

Does anyone have any thoughts?

thanks in advance.

 

[footgoose]

wow. Just looking at my spares I'd say if the splines haven't sheared off on the flexible coupling disc #11 below, (not likely)   then I'd say the paddles on the flexible coupling disc have sheared off #11 below (same piece) I don't see where else it could spin like that. otherwise it has to be a shaft key. (I am not familiar with this broken apart)

 

can you break it down a bit more to have a look?

 

[Antonio]

Hi,

nothing in the wheel is turning. It is only the big bevel gear (#29) that is spinning on its shaft

 

[Antonio]

the red arrows turn independently from the blue arrows

[Antonio]

Here is one more video. 

I will get back tomorrow. Need some sleep....

[Lucky Phil]

I would say that the gear and shoulder is a shrink fit on the shaft and its moved then eventually released. 

Ciao

[MartyNZ]

On 2/15/2021 at 6:15 PM, Antonio said:

the red arrows turn independently from the blue arrows

Wow, that's a nuisance. I have a pair of bevel boxes apart at the moment, and noticed that the crown wheel and bearing inner race are pressed onto the shaft/output spline. I even thought about separating the crown wheel off one shaft to fit to another shaft with an unworn output spline, thinking it may avoid the tricky job of shimming and setting backlash. But no.

Anyway for your problem. Bevel boxes in earlier Guzzis have a ring of big bolts that indicate high loads in the joint that failed on your shaft. Bearing retainer or epoxy may not make a strong enough bond. Brazing may work if your expert can avoid affecting the heat treatment of the teeth and spline. Otherwise you are facing replacement of the CW & pinion as a pair (or the whole thing).

 

[gstallons]

 T don't think I would buy a used R&P gear set & I don't know how much new is . It may be best (if it is a good price) to buy another assy. from someone parting out V11s . Keep us posted .

[bbolesaz]

Looks like part #29 is splined and the splines have been ground off.  The photo, looks like spline remains above the blue arrow closest to the gear.

 

[Lucky Phil]

12 minutes ago, bbolesaz said:

Looks like part #29 is splined and the splines have been ground off.  The photo, looks like spline remains above the blue arrow closest to the gear.

 

No thats just a reflection of the gear teeth. The whole unit is an assembly.

Ciao  

[bbolesaz]

Press fit?

[Lucky Phil]

My suggestion upon reflection is to have the shaft hard chromed to a build up of probably around .004" ( I'd need to research that) Ping Chuck! and then shrink fit it back on again.

Plenty of engine stuff these days use shrink or interference fit for things such as engine driven balance shafts and cam sensor wheels etc.

Ciao   

[Lucky Phil]

3 minutes ago, bbolesaz said:

Press fit?

Yes probably or shrink fit. Same interference fit by a different process.

Ciao

[Antonio]

18 hours ago, Lucky Phil said:

My suggestion upon reflection is to have the shaft hard chromed to a build up of probably around .004" ( I'd need to research that) Pink Chuck! and then shrink fit it back on again.

Plenty of engine stuff these days use shrink or interference fit for things such as engine driven balance shafts and cam sensor wheels etc.

Ciao   

Thanks everyone. I like this option as a starting point. 

I'll let you know how it goes.

Cheers.