Paralever bushings vs. OEM bearings?

[RT Russ]

I've got my 02RT down and tail in the air for transmission bearings and seals (dropped the trans off at Ted Porter's today). While the thing is disabled, I'm looking at what else I can do while it's unavailable. Does anyone have experience, good or bad with the bronze paralever bushings? I saw a damaged set on the counter at the BeemShop today and they did not have good things to say about them. Anyone else?

[OoPEZoO]

If the bronze bushings were damaged, then they were severely over torqued. I've been running them in my RT for probably 40-45k miles and when I pulled them to remove my final drive this weekend, they still look perfect.

[Peter Parts]

Hard to think of any ill-designed part of BMW which has cried out for replacement for so many years as those dumb needle bearings (of course I say the same thing about the whole Paralever nonsense).

 

Do it. But think-through your use of Locktite before using it everywhere recommended since you'll surely need to cinch-up later, eh.

 

Ben

[OoPEZoO]

Do it. But think-through your use of Locktite before using it everywhere recommended since you'll surely need to cinch-up later, eh.

 

Ben

 

Agreed........

 

They call for red locltite for all of the large fastener connections between the swing arm and final drive. Considering the size of the bolts, nuts, and threads, blue locktite (and a minimal amount) is a much better choice. I still get about half terrified when I have to break on of those bolts loose. Even with a little dab of blue, you still have to heat it plus use a breaker bar or impact wrench to get them broken loose. If you used red, I would really be afraid of doing more damage then good.

[4wheeldog]

200F degrees is the magic number where loctite lets go. Just sayin'.

[Matt, Kazoo]

I've replaced the needle bearings with the bushings from Rubber Chicken Racing in my 97RT, 2000LT, and now my 99RT. Never a problem. As with anything you do have to pay attention and not just toss the bushings in then reef down on the bolts. Use some common sense and a good torque wrench and all will be well.

[Peter Parts]

200F degrees is the magic number where loctite lets go. Just sayin'.

 

+1

 

I use an infra-red thermometer. Couldn't want a more perfect match of tool and task. Places like Harbor Freight and Princess Auto see 'em for around $35 or less.

 

But BMWs need anti-seize, Brit bikes need Loktite.

 

Ben

[dirtrider]

I've got my 02RT down and tail in the air for transmission bearings and seals (dropped the trans off at Ted Porter's today). While the thing is disabled, I'm looking at what else I can do while it's unavailable. Does anyone have experience, good or bad with the bronze paralever bushings? I saw a damaged set on the counter at the BeemShop today and they did not have good things to say about them. Anyone else?

 

 

Evening Hawk

 

Personally I have no use for them either. I’ve never had any issues with the production bearings and pins if they are properly greased & adjusted to begin with.

 

Some of the guys I ride with went to those brass/bronze bushings (claimed they were better) and they are all back to the OEM bearings now. But these guys aren’t just weekend riders they ride hard and use a lot of suspension travel and travel lots of hard miles.

 

In bulk those bronze bushings are a lot cheaper than the OEM bearings so if there were any way they were better don’t you think BMW would be using them as OEM install instead of the more expensive needle bearings.

 

[AndyS]

Personally I have no use for them either. Ive never had any issues with the production bearings and pins if they are properly greased & adjusted to begin with.

 

+1

 

Andy

[dan cata]

Personally I have no use for them either. Ive never had any issues with the production bearings and pins if they are properly greased & adjusted to begin with.

 

+1

 

Andy

 

I have paralever bushings and not an issue here. If installed correctly, they will last more than the bearings. They maybe do need adjustment every now and then but I did not get to that part yet.

 

And no loctite on mine, not the pins or the large securing nut. They did not come loose so far

 

Dan.

[ElevenFifty]

Bearings wore out at around 60K. Installed the bushings and they were fine for about 25K before wear dictated replacement. Went back to bearings - I probably screwed up the bushing install using blue loctite. Decision to go back to bearings was based on the fact that the original set had a long service life and they were immediately available at the local dealer. I saw no advantage to the bushings other than extended life but at 115K it is not likely that the bearings will wear our before I do. ;~)

[RT Russ]

 

 

 

 

Some of the guys I ride with went to those brass/bronze bushings (claimed they were better) and they are all back to the OEM bearings now. But these guys aren’t just weekend riders they ride hard and use a lot of suspension travel and travel lots of hard miles.

 

 

 

Morning Dirtrider,

Am I to read that the "use a lot of suspension travel" refers to GS and off road type of riding? As I research, the bushing info seems to imply that it will withstand a side to side rocking better than a needle bearing. I am guessing that this is more pronounced with off road riding?

I do not feel any notchy-ness in the OEM bearings, maybe I'll grease them when I put things back together and keep running them.

 

 

[dan cata]

Bearings wore out at around 60K. Installed the bushings and they were fine for about 25K before wear dictated replacement. Went back to bearings - I probably screwed up the bushing install using blue loctite. Decision to go back to bearings was based on the fact that the original set had a long service life and they were immediately available at the local dealer. I saw no advantage to the bushings other than extended life but at 115K it is not likely that the bearings will wear our before I do. ;~)

 

Right, installing them correct and adjusting when needed makes them more reliable than the bearings.

 

Just as a note, I do not sell them.

 

Dan.

[dirtrider]

Am I to read that the "use a lot of suspension travel" refers to GS and off road type of riding? As I research, the bushing info seems to imply that it will withstand a side to side rocking better than a needle bearing. I am guessing that this is more pronounced with off road riding?

I do not feel any notchy-ness in the OEM bearings, maybe I'll grease them when I put things back together and keep running them.

 

 

Afternoon Hawk

 

Yes, we ride rough roads mighty fast. Also some pretty harsh off-road but that is usually under 70 mph stuff. Still in all cases a lot of suspension travel and lots of swing arm cycles.

 

Personally I haven’t tried those bushings as I just haven’t had the need. The stock bearings hold up just fine for me. The guys I ride with couldn’t keep those bushings tight as they would come loose (or wear loose) then beat themselves to death in one or two rides. So now they are back to stock bearings greased up with good grease. I seriously doubt any of them will ever go back and try those bushings again. Two of the riders are plenty pissed as they replaced perfectly good OEM bearings with the bushings thinking they would be better.

 

I re-lube the stock bearings after the first year of riding then every 2 years after that. In all the BMWs I have owned I haven’t ever failed one stock bearing or tapered pin. One of the guys in my group actually drilled the center of the pins on his GS then added small removable screws so he can hit those pins with a needle greaser once in a while

 

[Peter Parts]

One of the guys in my group actually drilled the center of the pins on his GS then added small removable screws so he can hit those pins with a needle greaser once in a while

 

Not sure just how drilling a hole through the pins gets grease to the Paralever support bearing needles, unless of course the rider fills the swing arm full of grease.

 

Except for your worthy if compulsive attention to the Paralever support needle bearings, the rest your post likewise seems at variance with what most people who have tried the bushes think. Must be our sedate manner of riding compared to the manly and vigorous riding done by your pals.

 

One monumental stupid feature of the Paralever design is that the swingarm is no longer an airtight container of clean oil for the u-joint and spline like it used to be in earlier models (just one u-joint and one spline in the old model, eh).

 

Ben

[AndyS]

Except for your worthy if compulsive attention to the Paralever support needle bearings, the rest your post likewise seems at variance with what most people who have tried the bushes think. Must be our sedate manner of riding compared to the manly and vigorous riding done by your pals.

Your missing the point Ben, I would suggest the majority of riders are perfectly happy with what they have as OEM fit and rarely have issues if isntalled correctly.

 

One monumental stupid feature of the Paralever design is that the swingarm is no longer an airtight container of clean oil for the u-joint and spline like it used to be in earlier models

So running in oil with all its drag, is better than running in air?

I would rather have my shaft set up that has overcome the crazy 'rising & falling' than your rather rose tinted view of the old days and how engineering has gone backwards.

Is there anything you like about the modern BMW?

Andy

[dirtrider]

----Not sure just how drilling a hole through the pins gets grease to the Paralever support bearing needles, unless of course the rider fills the swing arm full of grease.

Think about it Ben-- It isn’t rocket science I’ll bet a number of readers here could figure out how to cross drill those pins to get grease to the needle bearings. The grease needs to go in from the outside then end up at the needles. How difficult can that be to figure out? The only thing needed is a high end carbide drill bit capable of drilling those harder-than-snails-nuts pins.

 

 

[Peter Parts]

RED TYPE ----- SERIOUS REPLY

 

OK... so it isn't just a hole through the pin. There is also some cross-drilling. Now lemme-see... the last needle bearing I looked at had some kind of shell, kind of like an orange. Ummm, I wonder if that would have to be drilled too in order to get some grease to the needles?????

 

 

AndyS -

 

People have been replacing and cursing the needle bearings as long as I can remember. Being something that doesn't get a lot of daily attention, sometimes they fail in some dramatic fashion on some dramatic location.

 

A lot of BMW riders think it is forbidden to replace or re-design pieces of the bike. Or even, God forbid, question German Engineering. Pity. (Those folks should read that survey respondents to Consumers Union think BMW leads the pack in bad new engineering ideas for cars.)

 

The newer bikes have enormous engineering improvements over each older series. Perhaps it is has evaded your attention that I drive a 1999 Oilhead. But a sealed drive shaft with no articulations seems a really great idea, compared to the theoretical problems which (ONLY) BMW think are present unless you have a Paralever gizmo... to introduce a host of worse problems.

 

BTW, failure of the swingarm bearings (near the battery) that had a grease hole, was all but unknown in the old series.

 

Ball's in your court, Andy.

 

Ben

 

Footnote for Andy and the young'uns here: the bike reputation of BMW was originally based on having just a few models, keeping them a long time, BUT every year debugging some pesky issue or other. For example, around 1963, they added a breather to the final drive so hot air wouldn't force oil out. Like the sound of that policy? Think they act the same today?

[nrp]

I modified my K1200LT OEM bearing pins by axially drilling the rear ones 1/16" diameter and cross drilling them to introduce grease into the side of each tapered roller bearing. I ground 4 small nicks in the side of the inner race so grease has a definite path to get to the rollers. To force the grease thru the bearing and not just into the housing, I added a hard aluminum tapered washer ~.008 thick that presses on the outer race of the bearing and is captive on the pin diameter/inner race. There is no seal or grease zerk on all of this - just a grease plug. I intend to lube it with a needle type grease gun AND using AeroShell 14 calcium based grease. I just did this last winter, so the jury is out.

 

It is important to use the right type of grease on these tapered roller bearings as the service will otherwise cause fretting. The AeroShell 14 grease is calcium based for helicopter applications. It is not expensive - unlike like the tiny tube of recommended BMW grease.

 

It also is probably quite important to not over preload these bearings as if you do, the shallow taper angle would raise the Herzian stress level of the rollers very quickly. On assembly, I set mine up so there is only a near zero clearance - maybe even the slightest amount of clearance.

 

My pre-retirement experience as an mechanical engineer involved many similar applications and service conditions with tapered roller and needle bearings. It is amazing what fatigue loads bearings can take.

[Peter Parts]

nrp demonstrates clearly (and writes very clearly too) that with enough sophistication and effort, a professional with a lifetime of specialized experience in rolling bearings can make the stupid and insufficient stock design work.... maybe.

 

You can will read in other forums, that these little needle bearings were a poor design choice for this small-rotation, shock-load, big force, application. If anybody disagrees with this conclusion and says it was smart engineering, let them say so right now.

 

For a few nickels, you can just buy the bronze bushings, when snugging-up the needle bearings no longer helps.

 

Ben

[philbytx]

 

"It was smart engineering....."

 

 

 

 

[Selden]

You can will read in other forums, that these little needle bearings were a poor design choice for this small-rotation, shock-load, big force, application. If anybody disagrees with this conclusion and says it was smart engineering, let them say so right now.

 

For a few nickels, you can just buy the bronze bushings, when snugging-up the needle bearings no longer helps.

 

Ben

+1 At ~70,000 miles, my 1999 RT had noticeable side-to-side rear wheel movement. Rather than tighten the OEM needle bearings, I went with the Rubber Chicken bronze bushings. When we pulled the OEM bearings, they were badly brinelled. If the bronze bearings are properly installed, and then snugged up after 400-500 miles, I believe they are a superior solution. A home mechanic who can't install the bushigs properly probably can't install the OEM needle bearings properly either, and will likely have a similarly poor outcome.

[nrp]

I think that since some of these bearings do survive, that it is lubrication and preload that determines life, and not an inherent weakness in the bearing. The bearing loads in this application should be fairly consistent between users. I suspect a major difference is the amount of preload that happens to get built into the assembly.

 

The published method of applying a tiny torque to the pin and then holding the pin while the jam nut is tightened down could well result in a very wide range of final preload. A little water combined with the poor water tolerance of calcium based greases & pretty soon the bearing frets out.

 

Frequent lube is definitely necessary - especially in wet applications. But removing all clearance in a fretting application doesn't help life either. That's why I don't feel to bad having a very small clearance.

 

It may be it is an application for Dupont's Vespel S21 or Amoco Torlon polyimide bearing stock running against a hardened and polished steel pin or race. The polyimides are quite expensive though.

 

Bronze is really only a temporary fix unless there is frequent re-lubrication.

[ElevenFifty]

DOH - that would be me. Actually one could consider the fact that my RT is running like a top at 117K miles something of an 'Hoorah' for BMW. Any machine that can survive being tended to by me for all these years deserves gen-u-wine BMW roller bearings!!

 

Probably deserves to be washed too, but not much chance of that.

 

Got play in bearings and a couple of days off ... get the bushings - haven't seen any technical argument not to.

 

Got play and leaving tomorrow - give your dealer the bucks and put in a set of bearings ... they will last for years - probably longer than the crown.

 

 

D ;~)

 

 

 

[philbytx]

 

I'm very happy with both my BMW motorcycles.......they run and handle very well and I enjoy them a lot.

 

There, I've said it! And if you don't agree with that statement, you'd better say so now !!