upper gear bushing

[SumpBuster]

Now that i've had mine apart and looked at how this thing works, i don't understand why there is a bushing at ALL.
We go in reverse maybe 50 yards ALL year at 10 rpm's so when it does spin, it would take a millennium to wear steel on steel even with NO oil.
Now i get if something was to wear it should be this bearing instead of the shaft.
But i would think the bushing should be just ONE notch softer then the shaft on the "Steel Hardness Notch List"

Like SteveO, the Avatar Swapping Maniac says, it wears from shock loading NOT spinning or RPM's.
Steel on Steel NOT spinning with a good fit and one drop of oil shouldn't wear at all. The coating is useless in my eyes. It wears & lets the gear get sloppy ruining people's trips.

Although my gear had 10,000 miles on it, i got lucky. My buds' at 3000 miles went bad at the beginning of a week long trip so we towed it home.
TRIP OVER!
That happened an hour after my coolant hose in the tunnel broke. Different thread, different rant.

P.S. I'm not sure if there actually is a "Steel Hardness Notch List", but you fellas know me long enough to get the OCD lingo

I don't remember (look it up later) what the delta box, or even the rx chain cases had on the bottom gear, which freewheels on the lower shaft (front axle, which turns much slower than the jackshaft, not that that means anything...but could) , as opposed to the top gear freewheeling on the jackshaft on the cat..maha. My lower gears fit and looked like new, as did every apex, vector and rx1s I changed tracks on, with reverse, of course...so....hmmmm. Smaller gear, more rpm, more hammering...? There is a reason for everything.

 

[SPM]

I have a take-ff 17 Sidewinder jackshaft on the shelf and I think I am going to see if a local machine shop has the equipment to check the hardness where the bushing rides. If it is hard enough, the bushing I posted about earlier should never wear out. It is a Copper, Nickel, Tin bronze alloy and has 5x the load capabilities of the SAE660 cast bronze bushing that is working for some (McMaster-Carr type listed previously by Clutchmaster).

I installed one of these toughmet3 bushings yesterday. They are definitely hard compared to original bushing. It has plenty of press fit into the gear. I trimmed the length with a lathe after installing it into the gear, drilled the holes and fit the I.D on a sunnen pin hone. There is no way a brake hone will work on this bushing as it's that hard and about .003 needs to be removed from I.D before it will fit the shaft. I set the clearance at .0015
The only bad thing is it's $40 from Grainger.

 

[Fast]

All I did was wrap 80 grit emery cloth around my finger and sand it to fit, 5 minutes. Then I polished it with 400 grit. The 660 bronze is slightly harder than the coated bushing and theoretically should last a bit longer.

Ya that's what i'm talking about,gotta like your new pic.

 

[twyztid]

I installed one of these toughmet3 bushings yesterday. They are definitely hard compared to original bushing. It has plenty of press fit into the gear. I trimmed the length with a lathe after installing it into the gear, drilled the holes and fit the I.D on a sunnen pin hone. There is no way a brake hone will work on this bushing as it's that hard and about .003 needs to be removed from I.D before it will fit the shaft. I set the clearance at .0015
The only bad thing is it's $40 from Grainger.

I found a different source for those bushings that has a better price. Do you think this bushing is too hard for the shaft or won't be a problem with an oil film between the bushing & the shaft?
Would it be safe to say that the only way to get a good fit with the ToughMet3 bushing is to have a machine shop hone them to fit the shaft meaning that the average person would never be able to open them up enough to fit on the shaft?

 

[cannondale27]

That’s what she said!

I knew you were going to say that!

 

[SPM]

I found a different source for those bushings that has a better price. Do you think this bushing is too hard for the shaft or won't be a problem with an oil film between the bushing & the shaft?
Would it be safe to say that the only way to get a good fit with the ToughMet3 bushing is to have a machine shop hone them to fit the shaft meaning that the average person would never be able to open them up enough to fit on the shaft?

I don't think it's going to hurt the shaft but it's definitely harder material than average bronze.
The I.D will definitely need to be fit by someone with access to equipment. The I.D could possibly be done on a lathe or maybe reamed but I chose to do it on a ridged style pin hone because I wanted a crosshatch finish for some oil retention. There is too much material that needs to be removed for a brake hone and to keep it straight.

 

[stevewithOCD]

I installed one of these toughmet3 bushings yesterday. They are definitely hard compared to original bushing. It has plenty of press fit into the gear. I trimmed the length with a lathe after installing it into the gear, drilled the holes and fit the I.D on a sunnen pin hone. There is no way a brake hone will work on this bushing as it's that hard and about .003 needs to be removed from I.D before it will fit the shaft. I set the clearance at .0015
The only bad thing is it's $40 from Grainger.

$40? That's it?
I lost a week around Maine because of this stupid little bushing
I blew $100 in gas towing the sled around to be fixed

 

[SPM]

$40? That's it?
I lost a week around Maine because of this stupid little bushing
I blew $100 in gas towing the sled around to be fixed

Actually....if the bushing that cost you a weekend was a factory bushing, they only cost
$4.59
I feel your pain....I've been there.

 

[twyztid]

I contacted a local bearing distributor about the ToughMet3 bushing. They contacted the manufacturer who said that the shaft should be a Rockwell hardness of C50 or higher. The bushing itself is a Rockwell hardness of C28 (or possibly might have been C30?).

I also contacted a local machine shop that I have used in the past at work. The owner told me that they make a lot of custom bushings out of that material (customer supplies the material because it is hard to get the material blanks). He says that the ToughMet3 material should last forever in that application (after I explained the application to him) and that a brake hone should work fine for opening up the I.D. a few thousandths to fit the shaft. I told him we have no idea how hard the jackshafts are so he said to just do the file test. I have a next to new 17 jackshaft here and none of my files would leave a mark on it.

Because of this information, I will be ordering 3 of the ToughMet3 bushings for a future gear for myself to use as well as the ones recently removed from my brother-in-law's ZR9000 and a friend's Sidewinder. This bushing may be the answer for those capable of getting them to fit the shaft.

 

[SPM]

I contacted a local bearing distributor about the ToughMet3 bushing. They contacted the manufacturer who said that the shaft should be a Rockwell hardness of C50 or higher. The bushing itself is a Rockwell hardness of C28 (or possibly might have been C30?).

I also contacted a local machine shop that I have used in the past at work. The owner told me that they make a lot of custom bushings out of that material (customer supplies the material because it is hard to get the material blanks). He says that the ToughMet3 material should last forever in that application (after I explained the application to him) and that a brake hone should work fine for opening up the I.D. a few thousandths to fit the shaft. I told him we have no idea how hard the jackshafts are so he said to just do the file test. I have a next to new 17 jackshaft here and none of my files would leave a mark on it.

Because of this information, I will be ordering 3 of the ToughMet3 bushings for a future gear for myself to use as well as the ones recently removed from my brother-in-law's ZR9000 and a friend's Sidewinder. This bushing may be the answer for those capable of getting them to fit the shaft.

Good info. Can I ask where you found the best price on these??

 

[twyztid]

Good info. Can I ask where you found the best price on these??

Applied Industrial Technologies... but ... their shipping price seems kind of high. They want nearly $20 to ship 3 from Ohio to Michigan. We have an account at work. I don't know if that is giving me a lower price than normal or not

 

[ClutchMaster]

I would be willing to try a slightly harder bushing but the soft coated bushing lasts a decent amount of time if there’s nothing wrong. Just fix the real problem.

660 bronze has been used for years as the bushing material of choice inside gear boxes.
They use it in heavy equipment pivot pin bushings, it’s one of the best materials you can use to prevent galling and wear on hard steel shafts.

If OCD’s sled can go 10k miles and not wear out but yours lasts only 2k, you have issues. I would try to solve the root cause problem instead of applying a band-aid fix.

M2C

All this talk of fancy sunnen hones, cross hatch for oil retention............................
I would think you guys are intelligent enough to understand that there’s something wrong with your chain, or tension your running.
Guys with big horsepower including me are not having issues with the super soft coated bushings.
Fix the root cause!

PS.
If that super hard bushing makes even circle scratch around that shaft where the bushing ends........take a guess what’s gonna happen to that hardened steel shaft?

 

[cannondale27]

All this talk of fancy sunnen hones, cross hatch for oil retention............................
I would think you guys are intelligent enough to understand that there’s something wrong with your chain, or tension your running.
Guys with big horsepower including me are not having issues with the super soft coated bushings.
Fix the root cause!

PS.
If that super hard bushing makes even circle scratch around that shaft where the bushing ends........take a guess what’s gonna happen to that hardened steel shaft?

I will say this one more time. You do not know if what you did to FINALLY make your bushing last a season is the fix since you did a lot more than one thing at a time and also did not put on the same miles and type of miles others do. It could just be driving style. Right now nobody knows what the solution is. Glad changing gears,tension and chain worked for you but it did not work for me. Only reason I have not tried more experimenting is the bushings are cheap and easy to change and I know I can get a season out of one without wrecking anything. Would be nice to not have to ever change it though. I appreciate all the experimenting.

 

[twyztid]

PS.
If that super hard bushing makes even circle scratch around that shaft where the bushing ends........take a guess what’s gonna happen to that hardened steel shaft?

You do realize that the ToughMet3 bushing is still softer than the shaft, right? How would you expect the bushing to "scratch" the shaft when it is made of a softer material?

 

[Turboflash]

All this talk of fancy sunnen hones, cross hatch for oil retention............................
I would think you guys are intelligent enough to understand that there’s something wrong with your chain, or tension your running.
Guys with big horsepower including me are not having issues with the super soft coated bushings.
Fix the root cause!

PS.
If that super hard bushing makes even circle scratch around that shaft where the bushing ends........take a guess what’s gonna happen to that hardened steel shaft?

I think it's safe to say there seems to be no definitive and absolute identifiable reason for the bushing wear, nor for why some of us experience no apparent wear at all. As Clutchmaster points out high HP doesn't seem to correlate. I have 300 HP with 21/38 gearing and have no wear at all over 3800 miles. Why? I have lots of long carbide studs so load cannot be a major factor. Yet, some with stock sleds have failure with very few miles like 1200 or less. Why? I wish we all could find out. Makes no sense. I run 1-3/4 turns out w Amsoil chain case lube. I still think harmonics/resonance plays a role.