Seals for Timken or other tapered roller steering head bearings?

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Thank you rPgoat and rbent for including your torque numbers. I completed my all balls tapered bearing install yesterday and took a short test ride and was happy with the upgrade. I torqued the first nut to 14ft-lb and I plan to go back in to check it and adjust it after a few hundred 'break in' miles. With your data I won't be afraid to run up to 20-22 ft-lb.

On my short test ride, which the bike was not heavily laden with luggage etc I could not induce a wobble in any of the conditions it used to appear. (cruise control at 35-45 mph, deceleration from 50 to 30) so I'm happy about that. At a steady 35 mph and cruise control on, I could induce a wobble by smacking the handle bars. But it wouldn't do it unless provoked. Even hands free over pot holes, etc wouldn't cause a wobble.

I need to load up the side cases and top case and see how the bike is then.

The installation was no cake walk. Getting old races out was fairly easy. Getting new ones in, especially the lower one on the steering head was a chore. I'm thinking I'll make an installation bushing or something to use when pounding on those suckers if I ever have to do this job again.
 
Thank you rPgoat and rbent for including your torque numbers. I completed my all balls tapered bearing install yesterday and took a short test ride and was happy with the upgrade. I torqued the first nut to 14ft-lb and I plan to go back in to check it and adjust it after a few hundred 'break in' miles. With your data I won't be afraid to run up to 20-22 ft-lb.

On my short test ride, which the bike was not heavily laden with luggage etc I could not induce a wobble in any of the conditions it used to appear. (cruise control at 35-45 mph, deceleration from 50 to 30) so I'm happy about that. At a steady 35 mph and cruise control on, I could induce a wobble by smacking the handle bars. But it wouldn't do it unless provoked. Even hands free over pot holes, etc wouldn't cause a wobble.

I need to load up the side cases and top case and see how the bike is then.

The installation was no cake walk. Getting old races out was fairly easy. Getting new ones in, especially the lower one on the steering head was a chore. I'm thinking I'll make an installation bushing or something to use when pounding on those suckers if I ever have to do this job again.
No need to pound them in. Just use a threaded rod and the pucks from your bearing driver.
1687187995387.jpeg
 
Tapered bearing fix shimmy issues that some people have with the stock caged roller bearings. Caged roller bearings are a weird application for a headset bearing anyways.

While I can't help OP on the seals for Timkens, as I've only ever used the AB kits, I did feel the need to comment on the spot about "why change bearings?" question.

The tapered bearings I installed on a sv650 gsxr1k Franken bike made my steering SOOOOO stable. I could take my hands off at 70mph and steer with my hips.

So yes I guess I will be getting about 100 bucks worth of tools and parts, and doing it myself.

Which I do have a note to add about jacking the bike up. I have an R-Gaza engine crash cage installed on my gen 1. It allows me to just use my straps on the cage to ratchet it up with the other side hanging from the steel beam rafters of my garage. I have already used this method for doing a tire change.
 
While I can't help OP on the seals for Timkens, as I've only ever used the AB kits, I did feel the need to comment on the spot about "why change bearings?" question.

The tapered bearings I installed on a sv650 gsxr1k Franken bike made my steering SOOOOO stable. I could take my hands off at 70mph and steer with my hips.

So yes I guess I will be getting about 100 bucks worth of tools and parts, and doing it myself.

Which I do have a note to add about jacking the bike up. I have an R-Gaza engine crash cage installed on my gen 1. It allows me to just use my straps on the cage to ratchet it up with the other side hanging from the steel beam rafters of my garage. I have already used this method for doing a tire change.
You can just stick jackstands under the gaza pucks too.
IMG_20210821_132330_1.jpg
 
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Shimmy is a complicated phenomenon that can have several causes. Frequency is around 10Hz and usually occurs at about 75Km/hr. Nose wheels on aircraft during landing can also suffer from it, and every effort is made to prevent it. The most obvious cause in motorcycles is dynamic imbalance in the front wheel or a top box. You should always balance wheels dynamically and not statically on a balancer. Shimmy can even be seen on a shopping cart swivel wheel. The advantage of a tapered roller bearing is that it has a little more friction to prevent shimmy starting up. I myself have also installed tapered roller bearings, but it is almost never the cause of shimmy. But if it helps prevent shimmy's startup, why not?
@Klikoo:
Why should you always balance tires dynamically? The factory roadrace teams use tires from B'Stone, Dunlop and Pirelli and ALL tire mfgs. balance their tires statically at Daytona. 180+mph. With no reason to cut corners at such a high speed track and all the resources to use "the best balancers" to showcase their products, why do you think dynamic balancing should always be done... especially when the mfgs. don't do it that way? (I'm technically curious, not being a d!@k trying to pick a fight)
 
Dynamic balancing will take into account any off-center weight distribution in more than one plane. You can actually get really close with static balancing if you place the weights either down the centerline of the rim or distribute the weights on either side of the rim evenly. Checking it dynamically will tell you how close you got it to perfect or you can do it dynamically from the beginning and get it spot-on right away. Part of the reason racing teams don't take the time to dynamically balance their tires and wheels is those guys are changing speeds very dramatically while they ride and, overall, ride at higher speeds. There's less time for the wheel/tire to get into a mode created by a slight imbalance than someone cruising at 70-80MPH for several minutes or hours at a nearly constant speed. I too am not trying to be a d!@k, just factual. :)
 
I think the run from the chicane to turn one at Daytona is more than a mile in 6th gear alone, flat out. Though I believe everything you say is technically true, I also believe it is irrelevant as to the rather narrow wheels on a motorcycle vs. that of an auto (especially an F-1 car with 12" or more wheel widths). If there was ANY real life difference, the manufacturers would dynamically balance them. Fun dialogue, didn't think you were being a d!@k. ;)
 
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