[DirtyMike]

So check it out, friend of mine owns a machine shop and rides DH. He has the ability to make bearings and is hoping that possibly there might be a market for an upgrade bearing for DH bikes to use a ACB or tapered bearing for the main oivot. He has made a set for his bike already and seems they hold up super well, and give a noticable lateral stiffness increase. He is working on a set for me currently for the Blindside so I can run some too.

Overall, he is curious what people would be willing to pay for a set, seeing how it will always be a make to order system<seeing how many different sizes are around for different bikes>. He is curious if it is something that will be worth pursuing or not.

Sooo, whats the feedback from themonkey?

 

[tacubaya]

Why make them if you can buy them? I doub't SKF, FAG, INA etc doesn't make them the right size..

 

[DirtyMike]

Why make them if you can buy them? I doub't SKF, FAG, INA etc doesn't make them the right size..

I havent been able to find them for the size application for very many pivots on bikes. I also sure dont know of any bikes that come speced with ACB bearings either.

 

[TRS]

If you look there is bout 3 different sizes that cover pretty much everything. (probably more) A better sealing bearing would be nice. If they worked and sealed good then I would pay extra for that. But with use of the lubeable bearings I'm not sure if most would go for it. But that is only an a couple of brands right now.

 

[DirtyMike]

If you look there is bout 3 different sizes that cover pretty much everything. (probably more) A better sealing bearing would be nice. If they worked and sealed good then I would pay extra for that. But with use of the lubeable bearings I'm not sure if most would go for it. But that is only an a couple of brands right now.

He is getting a list of specs together of the most common and working on finding which will be the most profitable.

So servicable is a big plus? and a good seal.... Ill pass that on

 

[DIRTWRKS]

He is getting a list of specs together of the most common and working on finding which will be the most profitable.

So servicable is a big plus? and a good seal.... Ill pass that on

Most bearings are already serviceable, as long as you can remove the seal on one side you can clean them out and relube them.

I am sort of intriqued as to why no one else has tried this before, assuming that these ACB can handle the radial loads of this application and reduce some of that side play found on most standard radial bearings, then I am interested.

 

[DirtyMike]

This is were my Boy Jan and Myself are at with this idea, We have been dicking around with pivot bearing on our rides now for years, and we always notice the same problem. Its not that the bearing looses grease, or really gets loose, or isnt handling the load..... Its the impact. How Jan put it<machinist friend> it, the idea of a roller ball bearing for a pivot is a terrible idea on so many levels its just disgusting to think about..... Your taking a bearing that by nature is designed to spin, and using it in an impact application.

He has done some testing himself for different idea's, made some bushing kits for his old RM7, different style bearings for his Kona stuff like that< must be nice to have full access to every machine you can think of>

I called it the ACB, because thats what most people know them as...... But he made really small hi count tapered roller bearings.... very thick races, very small area for contamination to get in...... By hi count... I mean he litterally has 75 rollers in each side.

Now Jan is a machinist so his crap is super clean all the time, He was bragging about this to me, so I called him on it, said make me a set, Ill abuse them and let them get diety and really test them out for ya.....

I should have them in a couple weeks.... Ill let ya know what I think

 

[davec113]

Doesn't an ACB require preload? In auto applications (diffs and hubs), they are always preloaded, and the preload force is critical and usually not easy for amateur mechs to get right. If so, how is preload accomplished in a pivot?

 

[Gurney]

I would be very interested in a set for my Wilson. IMHO Devinci didn't think out their pivots, crap.

 

[blackohio]

Doesnt having a insanely large amount of rollers in it also make the bearing tolerances tighter and more susceptible to wear and impact issues?

 

[Tootrikky]

Doesnt having a insanely large amount of rollers in it also make the bearing tolerances tighter and more susceptible to wear and impact issues?

I would think having more surface contact would be beneficial wear and impact wise, probably tolerance wise too.

 

[DirtyMike]

Doesn't an ACB require preload? In auto applications (diffs and hubs), they are always preloaded, and the preload force is critical and usually not easy for amateur mechs to get right. If so, how is preload accomplished in a pivot?

Actually.... a differential is the only place the tapered bearings in automotive are preloaded.... In the wheels<if they use a tapered, not a hub assembly....think older ford and chevy truck> they will actually have a bit of freeplay.

Doesnt having a insanely large amount of rollers in it also make the bearing tolerances tighter and more susceptible to wear and impact issues?

I would think having more surface contact would be beneficial wear and impact wise, probably tolerance wise too.

What Tootrikky said. The idea here with the hi amount of smaller rollers is its actually increasing the surface contact area, on top of that the other acheivment is that the rollers themselves are getting multiple rotations when it cycles through the suspension, so your not getting impact in the same location like bearings we see in bikes now....

Think of this, the bearing in the main pivot on a bike moves what... Maybe a quarter inch at the absolut most. The ball bearings are getting what, a 1/4 to 1/2 actuall rotation at most.... so they are relativly impacting in the same location over and over. Next time you replace a pivot bearing, take it apart and look at the impacts on the outer race.... Its friggin scary that you can actually see that its impacting in the same area over and over.

According to Jan, the three benefits are one.. increased lateral stiffness from the taper, two..increased surface area contact on the actuall bearings, via the amount of bearings, and the fact that the bearing itself being a roller instead of a ball gives more contact as well... 3... Easier to service, you can use a seperate seal that is mroe user friendly when working on the system.

 

[HAB]

I volunteer to test them.



Seems like a reasonable idea. If the price is manageable I can see them being a good option for replacements.

 

[blackohio]

cool, wasnt sure if my train of thought was correct or not. better bearings are always a bonus

 

[w00dy]

Normal cartridge bearings are usually spec'd because they are lightweight, cheap, and self contained (no extra sealing required). Don't get me wrong, my bike has straight needle bearings all around and I love it, but it's a cost/benefit question regarding a retrofit. For a set of these bearings (plus labor), how many sets of cheap, common cartridges would you be able to toast and replace?

From the factory I approve.
Schwinn had a crank set before they got bought out (BMX cranks) which had angular contact needles in the BB. Great idea. indestructable and you could set them a little tight for no-foot tricks without worrying about damaging the BB. My favorite headset of all time used them too (Solid one with steel cups). It was actually really light and small. This is where you'll see some needle bearings used. Turner and Superco jump to mind.
For the large frame manufacturer it doesn't make sense to build things with an unlimited life span. 4 years down the line everything you just sold is still running well and your new bike sales dip. Build it a little flimsier and you don't hurt future sales. It's called planned obsolescence, and it's in nearly every product you touch. Still makes me sick to think about it.
This is the reason I buy from small indie companies. Their market share is so small they don't have to worry about saturation. The only way they sell bikes is reputation based on unyielding quality. Turner and Superco are a couple of examples.

 

[DirtyMike]

Normal cartridge bearings are usually spec'd because they are lightweight, cheap, and self contained (no extra sealing required). Don't get me wrong, my bike has straight needle bearings all around and I love it, but it's a cost/benefit question regarding a retrofit. For a set of these bearings (plus labor), how many sets of cheap, common cartridges would you be able to toast and replace?

From the factory I approve.
Schwinn had a crank set before they got bought out (BMX cranks) which had angular contact needles in the BB. Great idea. indestructable and you could set them a little tight for no-foot tricks without worrying about damaging the BB. My favorite headset of all time used them too (Solid one with steel cups). It was actually really light and small. This is where you'll see some needle bearings used. Turner and Superco jump to mind.
For the large frame manufacturer it doesn't make sense to build things with an unlimited life span. 4 years down the line everything you just sold is still running well and your new bike sales dip. Build it a little flimsier and you don't hurt future sales. It's called planned obsolescence, and it's in nearly every product you touch. Still makes me sick to think about it.
This is the reason I buy from small indie companies. Their market share is so small they don't have to worry about saturation. The only way they sell bikes is reputation based on unyielding quality. Turner and Superco are a couple of examples.

Exactly, these arent going to be cheap, specially seeing how its a build to specs as oredered type process for a bearing that doesnt exist. Jan doesnt have a problem making them, he just wants it to be worth his while. His biggest concern is that it will be worth his time and materials to make any.

I see interest in them....... Anyone have a dollar amount they would put on this for themselves?

 

[Welshy.]

I see interest in them....... Anyone have a dollar amount they would put on this for themselves?

That's a difficult question. The actual cost of cartridge bearings from your average seal shop is pittance, whereas the price for the 'all singing, all dancing' bearing kit straight from the frame mfg is a complete slap in the face.

In order for these to be successful, they would need to be easily accessible, with an obvious (to even the slowest) in their performance increase. This is of course assuming they will be expensive.

But when you think about it, over here in Australia cartridge bearings cost between $2-8 a pop. Now take into account the frame mfg's want 10 times this amount for only a few bearings.

There is a lot of room for you to either undercut the large manufactures by just a little, yet maintaining the customer service that never ceases to amaze me when I go into the local.

God there's a lot of repeated **** there. Hopefully you can derive from that what you need.

 

[davec113]

Actually.... a differential is the only place the tapered bearings in automotive are preloaded.... In the wheels<if they use a tapered, not a hub assembly....think older ford and chevy truck> they will actually have a bit of freeplay.

If you're leaving freeplay in a hub you're doing it wrong.

You actually want just enough preload to eliminate all freeplay, but not so much that it won't spin freely. In any case, the point is the range for getting preload right is about 1/8 of a revolution on the axle nut, then the nut is locked in place.

When I owned a shop I specialized in off road and have rebuilt a couple dozen front axles


I guess I just need to see the bearing you're talking about, because I'm thinking it's like a tapered wheel or dif. bearing, and it would need to be preloaded into it's race. The only other places I've seen acbs on a bike are headset and cranks, and in both application the preload needs to be set.

 

[uncle-mofo]

This isn't really anything new. My 2006 DHR has ACBs in the main pivot.

 

[Tootrikky]

I am actually trying out some Oil impregged Bronze bushings in lieu of the Stock needle bearings on my Turner. The needle bearings index to fast imo most likely due to the limited rotation (less than 50 degrees?). Smaller needles would help due to more surface area therefore less pressure and probably reduce indexing as the rollers would spin more for the equivalent amount of suspension movement. However with more contact area you will get more friction (which could be countered with tighter tolerances) but still then cost goes way up and you still would have more friction...hmm How about make a bushing that has very little stiction, lasts longer, and weighs less! Then I'll be interested.

 

[DirtyMike]

If you're leaving freeplay in a hub you're doing it wrong.

You actually want just enough preload to eliminate all freeplay, but not so much that it won't spin freely. In any case, the point is the range for getting preload right is about 1/8 of a revolution on the axle nut, then the nut is locked in place.

When I owned a shop I specialized in off road and have rebuilt a couple dozen front axles


I guess I just need to see the bearing you're talking about, because I'm thinking it's like a tapered wheel or dif. bearing, and it would need to be preloaded into it's race. The only other places I've seen acbs on a bike are headset and cranks, and in both application the preload needs to be set.

Uuuuuh.... no. Think standard 4x2 front end work truck.......big taper on the inner, small taper on the outer..... Yes, those are freepaly, not preload. Preload on these equals smoked bearings..... Im measuring the freeplay with a Dial indicator, its specced usually tight enough you cant feel it by hand, but you can read it on the indicator. Now there is alot of newer stuff, that IS preloaded, usually 4x4's and hub assembly type bearings.

 

[tacubaya]

Tootrikky: It's called a needle bearing.