V-Max Speed Wobble (ran it up to 115mph and...)

[Fire-medic]

Be sure to replace the outer shells! Don't cheap-out because the upper is hard to remove. Lots of posts on here about how to do it: some welding bead, 180 degrees apart, using a Dremel or other cutoff disc seem to be two favorites. The lower has a shoulder you can catch w/a driftpin or a chisel. The upper is what takes time.

 

[88bradb]

Of course it starts that gentle weave/wobble. This time, I got brave and latched onto the bars real good and exerted quite a bit of forward pressure (instead of pulling equally backwards with both hands or just trying to grip the bars tighter, I pushed forwards equally with both hands). This did something because the wobble immediately stopped. I was out of safe pavement at that point or I would have pushed the bike faster....

My question is, what does this mean? I'd say this definitely points to steering head bearings/adjustment on my ride.

Progressive fork springs took care of my death wobble.

 

[sparky4123]

I just cut a piece of flat bar to drop most of the way into the race, then lightly weld it into place. Then it’s easy to tap the race out. Probably the bit of heat you apply when welding helps loosen the bearing as well.

 

[Shuriken]

Thanks for the idea. I can probably get a guy over and have it done for maybe $50. Or I have various grinders, including a Dremel somewhere, in which I could cut "dannymax groove" and then push it out with a punch. Come to think of it, $50 is way cheap compared to the hassle of grinding.....

I'm certain that the condition of these bearings and races and head torque are at the very least part of the problem I initially reported here. However, I also believe I'll end up working on the rear end of the bike as well, such as new/modern rear shocks at a minimum.

Back to what 88bradb said regarding front fork springs.... these are the fork springs I have now. I have no idea if these are OEM or aftermarket. Maybe someone more knowledgeable can tell by this pic. Front springs and rear shocks would be easy after dealing with head bearings.

 

[Gtista]

Shuriken's pics of bearing races show they, particularly the lower outer race, are totally shot. Maybe due to someone in the past trying to cure a wobble by over torquing? Anyway, wobble issues aren't going away until bearings are replaced.

 

[Tom Determan]

Throw a wet rag over the top to catch the sparks and one down inside. Set your welder like you're trying to weld something and get some penetration, don't lay a cold bead on top. Use a MIG or stick and weld a bead about 1/3 of the circumference of the race on one side or even less on 2 sides. Weld towards the bottom where the "meat" of the bearing is. When it's cool you can lift it out.

 

[Shuriken]

Shuriken's pics of bearing races show they, particularly the lower outer race, are totally shot. Maybe due to someone in the past trying to cure a wobble by over torquing? Anyway, wobble issues aren't going away until bearings are replaced.

When I took off the wheel and forks to relieve the weight on the steering head, and then proceeded to turn the bars, I couldn't believe what it felt like..... a little hard to describe but it felt overtight, NOT smooth, and with a variance when centered versus when turned side to side. It also felt dry.

I was actually surprised to find some grease anywhere in the steering head but the grease felt like glue. Basically, I'm going to make a guess that this is a 1985 steering head bearing and 40 year old grease....

You can also see from the pics that there is dust inside the steering head.

If I rode a mountain bicycle that felt this bad when turning the handlebars, I'd say it had been left out in the rain or maybe even the desert sun for too long. Either way, a dry bearing feel....

While I wait for parts, does anyone know what grease should be used on these bearings? Another thread I read suggested packing the entire steering head with grease. Any comments on that idea?

 

[Fire-medic]

Some observations.

'Brinelling' is the 'notchy' feel you get from having a steering head bearing go bad. It can be too-loose, too-tight, lacking grease, or contaminated grease. Too-many wheelies/hard landings will also cause that 'notchy' feel as you swing the bars from one side to the other, and you can feel the bumps.

A normal moly chassis grease will do the job, buy something name-brand, just to make you feel good about the purchase. I see no advantage to packing the steering head with grease. If there was, the factory would do it.

 

[Shuriken]

Awesome. Thanks for the help.

Got some time after work and had some success. I didn't have a welder so I had to grind with my die grinder.

Having now experienced this, I will recommend the welding method instead. It's too easy to jack up the bearing seats, frame, etc.

 

[Shuriken]

A few more pics...

If someone has any great advice on how to get the triple tree shaft bearings and seat off, I'm all ears. I'm thinking of a grinder and cutting wheel again since I don't have a welder...

 

[Fire-medic]

Yes, a cutoff disc and two slots 180 degrees apart, and then a cold chisel in the cuts to split the bearing. Use a die grinder.

Harbor Freight has a 3" cutoff disc & mandrel whose size should be good to make the cuts w/o cutting the stem.

 

[Radioguylogs]

I use a thick 3/4" wide chisel to get the bearing off of the triple tree shaft. It acts as a wedge.

For the races in the steering stem, I try to pound them out with a drift and chisels and misc tools. If they don't oblige, I cut them with a Dremel cutting wheel.....but it looks like you got the races out already.

 

[Shuriken]

I couldn't differentiate between bearing race steel and shaft steel during grinding and marred the triple tree shaft up enough that I don't want to use it. So... off to eBay or elsewhere to get a replacement.

I realized too late that once you cut off the bearing cage, the bearing race has a lip on it which can be used with the bearing puller tool or with a chisel in a prying motion...

So this sucks but lesson learned.

May be able to adapt this wrench to work with a torque wrench. And...yes... the civilized way to pull the bearing race would be with an expensive puller tool...

 

[Shuriken]

Just posting a couple of links to various tools for anyone who might take on this project in the future. Over the past 20 years, there really have emerged some great specialized tools for jobs like this.

1. https://www.amazon.com/gp/product/B00K3BNLHA/ - Motion Pro 08-0558 - steering stem bearing remover (should have done it this way)
2. https://www.amazon.com/gp/product/B004MZNP5Q/ - steering head spanner wrench
2a. https://www.revzilla.com/motorcycle/stockton-compact-spanner-wrench?sku_id=1124110 - steering head spanner wrench
3. https://www.revzilla.com/motorcycle/motion-pro-yamaha-spanner-nut-socket?sku_id=1005741 - steering head socket

 

[Fire-medic]

Use of the Motion Pro stem bearing removal & installation tool

 

[Tom Determan]

Just posting a couple of links to various tools for anyone who might take on this project in the future. Over the past 20 years, there really have emerged some great specialized tools for jobs like this.

1. https://www.amazon.com/gp/product/B00K3BNLHA/ - Motion Pro 08-0558 - steering stem bearing remover (should have done it this way)
2. https://www.amazon.com/gp/product/B004MZNP5Q/ - steering head spanner wrench
2a. https://www.revzilla.com/motorcycle/stockton-compact-spanner-wrench?sku_id=1124110 - steering head spanner wrench
3. https://www.revzilla.com/motorcycle/motion-pro-yamaha-spanner-nut-socket?sku_id=1005741 - steering head socket

 

[Tom Determan]

The Motion PRO stuff is top shelf, well designed, well made, and looks pretty on the tool wall, too.

 

[Shuriken]

Ordered one of the MotionPro tools. Hopefully it works slick.

Reassembling forks using a homemade damper rod holder. 3ft rod with 4 nuts of approximately 24mm od.

Also ordered some braided brake lines and already have pads.

Hopefully I can button everything back up by next weekend if the triple lower arrives in time.

 

[Shuriken]

Got the replacement triple tree lower yesterday, although the bearing puller tool hasn't arrived yet.

Couldn't stand to just sit there and stare at parts and wait for the mail truck. So after having screwed up on the previous bearing removal, I learned enough to do a better job this time. So with no bearing puller anyway, I decided to give it another shot.

This time, I cut off the roller bearing cage with cutting pliers. I also removed the rubber and soft metal wrapper around the base of the bearing race. After using a punch tool on the narrow bearing race lip and seeing the lip fracture (yes, wear safety glasses!) and zing away, I realized I'd have to apply force to another area of the bearing or wait for the puller tool.

After positioning the assembly across some wood blocks, I chose to do some very careful grinding this time to heat up the bearing race and also to weaken the bearing and provide some notches which I could use with a punch tool. Then I moved on to the punch tool. I was eventually successful seeing the bearing move when using a punch positioned at the base of the bearing at it's strongest point and tapping with a hammer. Taking care to tap as evenly as possible around the base, the bearing came off pretty uneventfully.

The old bearing and more careful work with a punch and hammer worked perfectly as a driver to drive the new one back onto the shaft. A driver is necessary to avoid damaging the new bearing roller cage.

After application of good, high quality grease, everything went back together. The front end movement is definitely and obviously waaaaaay smoother now. I'm at the point now where I am torquing, rotating, loosening, torquing, testing, etc. Forks and wheel, bars, headlight, and other front end parts are back together. Now I need to figure out an affordable brake line replacement while I refill and work on front forks.

 

[Shuriken]

Pics...