ST1300 - Roller Bearing to Taper Bearing Upgrade for Steering Head - Warning

[St1300biker]

One guy I have huge respect for on Youtube when it comes to motorcycle repairs is Shane Conley. He doesn't pretend to be an engineer, but having followed him for years I can tell you he knows his stuff.

He recently posted a video:-

Although generic, the important points he makes starts at 2:15, and to be honest I was shocked at what he discovered. Although I haven't yet replaced/upgraded my steering head bearings, I know a number of members on this forum have.

Shane concludes that if you buy OEM parts you will never have problems with those parts integrating with the surrounding parts. However, the same cannot always be said of aftermarket parts advertised as being suitable for a particular machine - even if well known brands..

So my question to those have done the upgrade is:- "Did you notice the gap that Shane discovered, and if so what did you do?. Is this a non-issue for the ST?"

Paul

 

[Igofar]

After removing a few sets of tapered bearings in various ST's over the years, my personal opinion is to use only the OEM style ball bearings in this application.
They are easier to set to the correction torque, and are a better choice for the application.
Steering bearings have limited movement from side to side, and ball bearings are the correct choice IMMO.
Thanks for sharing the video.

 

[Uncle Phil]

Not much of mechanic here, but I've run the roller bearings in my steering stems from CBR in all 4 of my ST1100s for a bunch miles and no problems so far.
YMMV.

 

[Bush]

If the OEM ball bearings were given the same diligent attention to maintenance that many of us do with the rest of the machine, they should last a very long time indeed. The most important item of maintenance not done for virtually every new ST sold was the re-check of the bearing torque after the first 1,000 miles. How many here can say they did that with their brand new ST11, or ST13?

I did on my new '95 ST and they were still in great shape when I sold the bike in 2014 with 175,000 km on it. I had also removed and re-lubed them twice over the years. My '96, bought used at 72,000 km, also still has the balls, which i disassembled and re-lubed when I bought the bike in 2014.

It isn't the easiest bit of maintenance, having to disassemble the entire front end and I imagine that is why so many failed long before they should have.

 

[bdalameda]

Whenever you change to a different type of bearing you need to consider spacing etc., that is a given. Personally I have used tapered roller bearings for years on steering stems without any issues. Any high performance motorcycle in racing applications use these bearings for good reason. The type of load and the amount of bearing surface area is greater to handle a higher load - overall a stronger and stiffer bearing assembly. That being said the adjustment is critical on tapered roller bearings and there seems to be less tolerance for making adjustments for tapered roller bearings vs. the oem bearings on the ST Hondas. Most larger new bikes are now equipped with tapered roller bearings.

 

[rwthomas1]

Nothing wrong with ball bearings in the stem, but the roller will have more surface area contact. Does it matter? I'd guess on a street ridden machine, not even a bit. The biggest issue is maintenance. Nobody every lubes them. Ball or roller still need attention. Should have designed stems with grease fittings....

RT

 

[mlheck]

Should have designed stems with grease fittings....

RT

I've seen several HD's that actually have this. Who would have thunk.

 

[GGely]

I've seen several HD's that actually have this. Who would have thunk.

Do they leak?

 

[mlheck]

You had to go there......

 

[2turbos]

Nothing wrong with ball bearings in the stem, but the roller will have more surface area contact. Does it matter? I'd guess on a street ridden machine, not even a bit. The biggest issue is maintenance. Nobody every lubes them. Ball or roller still need attention. Should have designed stems with grease fittings....

RT

How do taper bearings have more contact? Both kinds of bearings have line contact.

 

[rwthomas1]

How do taper bearings have more contact? Both kinds of bearings have line contact.

The length of the roller bearing element has, generally, more length than the line contact area of the spherical bearing element. At least that has been my experience messing about with machines in my professional and personal life....

RT

 

[St1300biker]

Should have designed stems with grease fittings....

See the following video:-

Do you still think that?

Paul

 

[SMSW]

How do taper bearings have more contact? Both kinds of bearings have line contact.

Ball bearings have point contact with a flat surface, realistically, just a small circle or oval on a curved race. As @rwthomas1 said, the roller bearing has a line of contact on a flat surface, or an extended oval the length of the roller on a curved race. The roller bearing will have a larger surface area for a given diameter of rollers and balls. If you want a ball bearing to equal the load bearing capacity of a roller bearing, you will have to increase the diameter of the balls.

 

[SMSW]

I just watched the video and he misses two points. Bearings and grease fittings, like everything else are a system and have to be designed and treated as such. A properly located zerk top and bottom (for the two bearings) would also require baffle plates and some sort of seal around the shaft to keep the grease near the bearing. Alternatively, (and I say this because said seals would increase friction of the steering shaft) one could expect to fill the whole steering tube with grease, like we do the inside of wheel hubs and brake disks (that don't simply bolt on to the hub) and then use a top and bottom zerk. And of course, seals would be necessary top and bottom. Yes, grease nipples are useful - why else does every excavator have dozens of them? But they aren't simply scattered around like sprinkling salt and pepper.

 

[St1300biker]

I just watched the video and he misses two points

He also makes the point that, if you rely on the zerks, the bearings don't get inspected.

Paul

 

[rwthomas1]

See the following video:-

Do you still think that?

Paul

Yes, yes I do. Inspecting the bearings? How many actually do that? Very few. And does it need to be done? I'm sure some will argue yes, but simply checking the freeplay once a year and feeling for "crunchiness" or "detents" when swinging the triple tree back and forth is enough. The reality is that steering head bearings don't move very far, and they tend to wear in one place, due to the fact that the handlebars spend much more time in the centered position than actually turning. Even greasing in this case isn't really going to keep this from happening. Still would be nice to have a zerk to shoot some lube in there for good measure.

Tear down the bike yearly and grease the stem bearings, or just tear it down every 10 years and replace them? Whats easier and makes more sense?

I've spent a significant portion of my careers in industrial vocations. We don't tear down anything to inspect the bearings unless there is some indication there is a problem. Noisy? Vibrating? Chattering? Heating up? Yeah, its coming apart. But the rest of the time the equipment gets a PM lube service on the oil bath or grease shot in through zerk fittings.

I will check the triple tree at the beginning of the riding season. Check for excessing play, roughness, detent-ing, etc. If all is well, thats it. If I could sneak some grease in with a needle, I'd do it. But that is it. Others can do what they are comfortable with or feel is necessary.

RT

 

[SMSW]

He also makes the point that, if you rely on the zerks, the bearings don't get inspected.

Paul

He did, and I'm of two minds about that. On one hand, you don't need to inspect the bearings if you are going to give them a shot of grease now and then (tapered roller bearings on cars handle much larger loads, I would think (this is a guess, I don't know any loading numbers) and run for years without repacking). On the other hand, who pulls the head bearings apart for cleaning, inspection, and repacking if there are no indications of notching or roughness or looseness? Loosening and torquing the steering head nut when you do the fork oil, maybe, otherwise, how many of the obsessive maint. mechanics among us do the strip down inspection and how often? Why does shooting grease in a zerk fitting replace a full teardown if that is what the mfr dictates in the service manual, or notchy steering calls for it?

If this mechanic thinks zerk fittings make us ignore a needed inspection, he has not read the threads here about thick soup coming out of brake and clutch lines and the other ills caused by deferred (read ignored) routine maintenance.

I honestly don't know if a shot of clean grease in the steering head tube for upper and lower bearings will lengthen their lives. Only a long term multi bike test program will answer that. Common sense says it cannot hurt (worst case) and it might increase their life (best case).

 

[Jambriwal]

I have installed tapered steering head bearings on 3 different motorcycles. 1978 SR 500 Yamaha and added Zerk fitting to swingarm. All to improve handling and movement of parts that are supposed to move. Seat of the pants impression, seemed to help.

Also a VTX 1300 and a 2014 Valkyrie 1800. Both bikes exibited low speed occilation from 45mph down to 30mph. Success, improved both.
One thing i never understood was the complicated procedure for torqueing steering head bearing. Wheel bearings replaced is usually a two step process. Tighten to a pre determined tourque, loosen and final setting.
Seems most factories today use guns to fasten everything. If someone is doing the swingaway test to every motorcyle wouldn't that clog the line. They of course have the advantage depending on the level of assembly reached at that time. If someone could enlighten me I'm willing to listen.

 

[ST Gui]

simply checking the freeplay once a year and feeling for "crunchiness" or "detents" when swinging the triple tree back and forth is enough.

And I bet a very large percentage of riders don't even do that. Every thing is fine - until it isn't. Bike wanders / uneven tread wear / odd vibration - check the steering head bearings.

"Annual inspection time! Lessee- flush and bleed the clutch and brakes / inspect the pads / check all fluid levels - oh and disassemble the front end and check the lube on the steering head bearings." Yeah- no.

 

[SMSW]

Seems most factories today use guns to fasten everything. If someone is doing the swingaway test to every motorcyle wouldn't that clog the line. They of course have the advantage depending on the level of assembly reached at that time. If someone could enlighten me I'm willing to listen.

I cannot bring you enlightenment, that's your job. However, if you have seen the youtube videos of auto engine assembly, then you have seen multi spindle power sockets tightening all of the cylinder head bolts simultaneously (and con rods, etc.) to the appropriate torque. Honda must tighten steering head nuts the same way - and they could even test the fork's swing automatically at the same time.