Pivot bolt not fitting through frame. Ideas?

[Jeffodman]

Hi guys,

I got a new pivot bolt from Mike's for my '82 Heritage Special since the old one was beat up and slightly loose. The new bolt goes through the tube inside the swing arm perfectly, but does not want to fit through either side of the frame (bolt is too thick). I oiled it up and smacked it hard with a mallet a few times but only managed to get it stuck about 1 mm in. I'm guessing this is not normal so I knocked the bolt back out. Should I be machining the holes in the frame? That seems kinda ridiculous. Any recommendations?

 

[weekendrider]

Is there a difference in diameter old vs. new?

 

[Jeffodman]

Is there a difference in diameter old vs. new?

Yeah but it's a very slight difference (not sure how minute since I don't have a micrometer). The old bolt fits through the holes in the frame perfectly, but is a little too loose inside the tube. The new one doesn't fit through the holes in the frame but fits snug in the tube. I'm wondering if these new bolts are made a bit oversized to pick up slack from wear. Anyway, I guess I will have to hone or ream out the holes a little bit.

 

[weekendrider]

Or reduce the shaft?

 

[fredintoon]

Hi Jeffo,
if the bolt already goes in part way it's likely 0.001" or less too big.
The rigorous fix would be to reduce the shaft diameter using emery tape, which will be way easier to do if you can spin the bolt in a lathe.
The quickie fix is to open up the holes in the frame with a small diameter flapper-wheel in a hand-held power drill.
Remember that after installation the through bolt and the bearing sleeve will be locked solid in the frame so that excessive clearance will not be a problem.

 

[Bob Kelly III]

Sense I've had to fix my share of bolts in my time I'll say something.....
a rat tail file used to JUST clean up the hole is probably all you need.... don't get carried away and spend hours on it ! just clean the burrs off till it slides in and out good .....
Fred I've never seen a flapper wheel small enough to go into a 3/4" hole before so maybe a reamer would do the trick eh ?
or I guess you could make one by cutting a slit in a rod and putting sandpaper in the slit and then put the rod in the drill ! LOL
where there is a will, there's a way !
Bob..........

 

[fredintoon]

Hi Bob,
and there's your 25.4nicating problem. Them holes ain't 3/4"' they's 0.0049" bigger'n 5/8"
Although come to think about it, I ain't seen a flapper wheel smaller than an inch either.
But nah, a reamer would be total overkill just to kiss those holes out a bit besides being
appallingly expensive and most likely the OP would have to go out and buy one because
a set of reamers ain't usually part of a person's tool kit. Although they can be rented.
One time I rented an expanding reamer to open up a pair of bronze swingarm bushings
that slid over their bearing sleeve just nice out of the package but spitefully closed up
after I pressed them into the swingarm.
If not a flapper wheel there's all manner of little grinding bobs in most folk's Dremel tool kits
Or perhaps a round file?

 

[Bob Kelly III]

Oh well, 5/8" 3/4" ...close enough to know a flapper wheel ain't gunna' fit..... I'ed just use my chainsaw file on it and be done in 5 minutes !
and DON'T bugger up the threads by pounding on it with a hammer ! ehhehehehehehe !
....
I've had bushings shrink a tiny but when being pressed in but nothing like that ! LOL must's been a really small hole !!!!! or real thick bushing !
i have 2 big long reamers that start about 1/2" and go to 3/4" in a slow taper they are very handy ! My Step Dad had them for Ford F-350 A-arm bushings if I remember correctly ! ....now there was a truck.... he put a 6 cyl Perkins diesel in it ! LOL and a brownie 3 speed behind his 5 speed ! the trck weighed in at 15,000lbs ! and he called it his baby pickup ! he could carry 5 tons of gravel at a time with it !
....
Bob.......

 

[fredintoon]

Hi Bob,
the bushings slipped on perfectly before I pressed them in. I doubt the shrinkage/misalignment after the press fit was more that 0.001"
Just enough to need an adjustable reamer to open them up enough that the sleeve would slide through.

 

[Bob Kelly III]

the Only Adjustable Reamer I've ever used was a Piston ridge ring remover ! LOL and that really don't count in this case i'm sure
they must be 3 cutters that expand from the inside that you turn with a wrench eh ? like a tail pipe expansion tool .....
......
Jeffodman: did you get that thing to fit yet ??? didn't mean to high-jack the thread here ! LOL
Bob.........

 

[kshansen]

Well if all else fails one could take a piece of 1/2 bar stock about 3 inches long. Cut a slot down the center and fold over a couple inch long section of emery cloth and slip it into the slot and give it a whack to tighten it up on the emery then chuck it in you drill motor and slip in to the hold and have at it!

 

[Bob Kelly III]

i made one similar to that out of a 1/2" axle I needed to have a long reach for something..... i cut a long slit in the axle and put a folded piece of 60 grit sand paper in it smacked it with a hammer so it would grip the paper and it cleaned up the inside of many things around the ranch ! i still have that axle and use it everyonce in a while I like using about 8" of emery cloth in it....better than that 60 grit! cuz it scratches the heck out'a stuff !
sometimes you need that though to get the rust off ! .... I think that rod has steel wool in it right now ! LOL it's about a foot long I was polishing a port with it last use !!!! ..... I need to buy some new wire wheels for the drill mine are all shot !
.....
I got my emulisifier tubes cleaned real good on the bike... now with some carb cleaner it should make quick work of cleaning those tiny convoluted passage ways for the choke and idle settings.... i figured I'ed break down and clean the carbs right this time...glad I did one emulisifier tube was green and dirty ! .... pilot jets I cleaned last time .... but I will pull them before I sprey them out ! ....
I used a wire brush wire to poke through the tiny holes in the emulsifier tubes ..everything else is too big !
....
Hay Fredintoon ! how far back from the center of your bikes wheels does your side car tire sit ? been meaning to ask you that for ages ....just guess.
.....
Bob..........

 

[Jeffodman]

the Only Adjustable Reamer I've ever used was a Piston ridge ring remover ! LOL and that really don't count in this case i'm sure
they must be 3 cutters that expand from the inside that you turn with a wrench eh ? like a tail pipe expansion tool .....
......
Jeffodman: did you get that thing to fit yet ??? didn't mean to high-jack the thread here ! LOL
Bob.........

Haha, yeah, I'm just now getting back to this thread! I got my hands on a micrometer and it appears that I need to shave of a tenth of a mm. So I ordered an adjustable reamer for about 13 bucks that goes from 15.25mm to 17mm, small enough to fit the hole with plenty of expansion. My plan is to shave out the holes bit by bit till I get a snug fit, but I haven't yet because Amazon neglected to tell me that the reamer would ship from China! So I have to wait for the damn thing to get here - it's looking like mid-April arrival.

 

[Jeffodman]

Hi Jeffo,
if the bolt already goes in part way it's likely 0.001" or less too big.
The rigorous fix would be to reduce the shaft diameter using emery tape, which will be way easier to do if you can spin the bolt in a lathe.
The quickie fix is to open up the holes in the frame with a small diameter flapper-wheel in a hand-held power drill.
Remember that after installation the through bolt and the bearing sleeve will be locked solid in the frame so that excessive clearance will not be a problem.

You're pretty much right. Turns out the shaft is .1 mm bigger than the holes. I talked to my dad and he suggested an adjustable reamer. So I ordered one of those and it's on the way. Thinning down the shaft isn't an option because it's such a nice fit in it's collar/sleeve whatever that part is called.

 

[Jeffodman]

Well if all else fails one could take a piece of 1/2 bar stock about 3 inches long. Cut a slot down the center and fold over a couple inch long section of emery cloth and slip it into the slot and give it a whack to tighten it up on the emery then chuck it in you drill motor and slip in to the hold and have at it!

Hey, not a bad idea! I ended up getting an adjustable reamer, but this would do the trick too.

 

[xjwmx]

I've got a feeling the new bolt is a thousandth or two larger than the original and the frame has a thousandth or two rust and grime in it. I would start by just twisting a Scotchbrite pad in the hole with some oil. It's surprising what a very thin, easily removed layer of crap can do to fit. If that didn't fix me, next I'd take a small rattail and go around the outside ends of the holes to get rid of burrs and dents.

 

[weaselbeak]

Well if all else fails one could take a piece of 1/2 bar stock about 3 inches long. Cut a slot down the center and fold over a couple inch long section of emery cloth and slip it into the slot and give it a whack to tighten it up on the emery then chuck it in you drill motor and slip in to the hold and have at it!

Been using this "tool" for many years. It is easily the best way to clean up a hole.

 

[kshansen]

Been using this "tool" for many years. It is easily the best way to clean up a hole.

So you're the one who is not paying royalties on my invention! If I post my email address will you send me some money today on PayPal?