V50 swingarm pivot won't install into bearing

[jamesfjamesf]

I'm installing the swingarm and the left side pivot pin won't slide into the bearing. The right side pivot pin slides into both bearings so it's the pin. It came out seemingly fine since it has the swingarm for the inner race to rest against, but going in there is nothing behind the inner race supporting it so I don't want to whack it.

I tried a bit of 400 grit sanding on the pin but it hasn't helped. I can't see a way to use heat/cold given how long it takes to thread the pin in. Has anyone run into this?

I have a friend with a lathe so I could do some machining on it if I had to, seems extreme though.

thanks,
jim

[guzzisteve]

If it came out it should go back in. There is also a shim that goes between the swingarm and frame w/pin, on left if I remember correctly.

[jrt]

I would measure all the parts in question.  Can you measure the diameters of both bearings and both pivot pins?  There is a special T shaped tool that will give you a good ID on the bearings (but a vernier will work).  Vernier calipers are great for the OD of the pins.
My copy of a workshop manual has the spacer on the right hand side.  (but that is a 2016 V7ii)

[Dirk_S]

My copy of a workshop manual has the spacer on the right hand side.  (but that is a 2016 V7ii)

I think I remember when perusing multiple small block manuals that they had switched the side.

I would remove the troublesome pin from the swingarm and try to fit it into the bearing (might as well try both).

If both pins fit into all bearings fine, and you still can’t get both to seat in at the same time when they’re in the swingarm, then perhaps the swingarm has wishboned at the pivot mounts? If that’s the same transmission case and swingarm as a V7 II (I think so), I measured the distances between the swingarm’s pivot mounting tabs to be 24.75cm apart (inside to inside).

[Scout63]

Is the bearing seated fully?

[guzzisteve]

Well, I remembered the shim but not the correct side, right side or on shaft side. Had to look in book having my coffee & cigar in garage. Getting old ain't for sissies.  Had my 1st bout w/Basil cell skin cancer, Dr cut it all out, size of quarter on cheek.

[jamesfjamesf]

In the reply window I can't see any of the previous posts, and like Steve says below, memory is something something so hopefully I address each idea. I measured the pins this morning - frustratingly both measure 0.5900". I've tried inserting the pins into the bearings by themselves without the swingarm in the way. Right pin easily goes into either bearing, left pin won't go into either. It gets about 1/8" in and stops like it's cocked, and I need to wiggle it to remove it. Even with liberal amounts of antiseize it seizes, almost like it's a super magnet. Maybe my issue is nuclear.

My first clue there was an issue was watching the swingarm spread apart as I threaded the pin in so the interference is substantial.

Well, I remembered the shim but not the correct side, right side or on shaft side. Had to look in book having my coffee & cigar in garage. Getting old ain't for sissies.  Had my 1st bout w/Basil cell skin cancer, Dr cut it all out, size of quarter on cheek.

Oof. I had a "hmm..let's cut that off and send it to the lab" slice removed from my calf last week. Given my invincible teenage sun worshipping I'm expecting that to be a regular occurrence pretty soon.

Shim goes on the right according to Guzziology and the Harper's fiche.

thanks,
jim

[guzzisteve]

Are the pins & bearings original?  I don't use anti seize, just synthetic grease. Same on pins thread.

[Moparnut72]

Well, I remembered the shim but not the correct side, right side or on shaft side. Had to look in book having my coffee & cigar in garage. Getting old ain't for sissies.  Had my 1st bout w/Basil cell skin cancer, Dr cut it all out, size of quarter on cheek.

I am going in for a checkup on my arms and head on Tuesday. Hoping for a clean bill of health other than freezing off a few small spots. A couple of my barnacles make me apprehensive though.
kk

[Mike Tashjian]

I would remeasure the pin and see if there is a burr or high spot.  Easy to remove with a file or small block of wood and sand paper once you find it.  A good clue is it's where it's starting to bind when it goes in. As an alternate method use a strip or sandpaper and sand around the pin like a old time shoe shine.  That may expose any high spots or other issue.  I sometimes chuck a part like that in the lathe and give it a quick polish after touching it lightly with a file. Key is to not remove any more than necessary. 

[matt franklin]

I would remeasure the pin and see if there is a burr or high spot.  Easy to remove with a file or small block of wood and sand paper once you find it.  A good clue is it's where it's starting to bind when it goes in. As an alternate method use a strip or sandpaper and sand around the pin like a old time shoe shine.  That may expose any high spots or other issue.  I sometimes chuck a part like that in the lathe and give it a quick polish after touching it lightly with a file. Key is to not remove any more than necessary.

Careful with that!  To polish the pin, the threaded portion needs to be clamped in the lathe chuck.  It would be easy to mash the fine threads on that pin, thus spoiling it

[Chuck in Indiana]

Careful with that!  To polish the pin, the threaded portion needs to be clamped in the lathe chuck.  It would be easy to mash the fine threads on that pin, thus spoiling it

Yeah, you need to put it in a collet to do that. Sounds like it needs to be done, though. People that have never dealt with close tolerance fits don't really understand how little it takes to make an interference.

[John A]

you could put some color on the pin so you could see exactly where its hanging up. Clean it all up and use a sharpie to color it , maybe it will reveal a spot

[jamesfjamesf]

Yeah, you need to put it in a collet to do that. Sounds like it needs to be done, though. People that have never dealt with close tolerance fits don't really understand how little it takes to make an interference.

I brought it to a machinist friend tonight and he measured it with +real+ calipers (apparently the 4th digit on my vernier caliper is just for show  ) and the stuck one was, at a certain diameter, .1 mm larger than the smooth one. He ran it through his grinder and now it fits smoothly. He did mention afterwards that we could have tossed it into a collet for a reasonable attempt at using the lathe but the effort involved wasn't worth the miniscule gains over just touching it up with the grinder.

Thanks for everyone's input; it helped make sense of a nonsensical thing.

jim

[Chuck in Indiana]

(apparently the 4th digit on my vernier caliper is just for show 

There's a reason machinists call *any* caliper "Very nears." 

[Mike Tashjian]

.1mm is quite a lot of deformation on a part like that.  I bet your friend barely touched it with the grinder. And really guys, we are trying to help people that do not have machine shops in their garage.  Many people will have a vise and using soft jaws can easily hold a threaded pin to polish off a high spot.   

[n3303j]

.1mm is quite a lot of deformation on a part like that.  I bet your friend barely touched it with the grinder. And really guys, we are trying to help people that do not have machine shops in their garage.  Many people will have a vise and using soft jaws can easily hold a threaded pin to polish off a high spot.   

.1 mm is 0.004" which is a fair amount of interference fit.
I'm wondering where this material came from.
Didn't the pivot pin come out of a working bearing?
How was the pin deformed?
Mushroom end, corrosion,  burr, eccentricity, etc?
If 0.004" was removed from a pin that used to fit then it would be a sloppy fit in the bearing and the rear swingarm would wander about as loading changed.
Was the pin a gage fit in the bearing after it was ground?

So many questions. If it came apart, then it should reassemble by reversing the order of steps. Why did it not?

(Unless it's a Ural where I've found bearings so tightly fit that they bound with no load applied, '96)

[jamesfjamesf]

So many questions. If it came apart, then it should reassemble by reversing the order of steps. Why did it not?

I don't know the answers to your first 10 questions (most of which I also had) but it fits nicely now so I don't care to disturb the sedated hornet's nest.

As for the quoted question, many people have asked the same thing, I've answered it in the thread a few times. The force required would have damaged the races in the same way wheel bearing removal is destructive.

jim

[n3303j]

"Fits nicely" is such a subjective term.
Do you know the clearance between the pin and bearing inner race?
The machinist should have verified that the clearance was cirrect.

[Pescatore]

So many questions. If it came apart, then it should reassemble by reversing the order of steps. Why did it not?

Jim mentioned the pin was going into the bearing 1/8inch.
My guess is that it wasn't all the way in to begin with.
Could be previous botched repair or from factory.
Lucky you for taking it apart. That was a ticking bomb.