Speed wobble

Hi everyone i have a seca 750 and around 70mph it starts to get a slight wobble. I am unsure what it is, i thought at first it was the tires, i replaced them. then i thought maybe it could be the front fairing due to the lack of glass over the head light thinking this could catch the wind. Now im guessing its the steering head bearing the bike has 24,000 miles on it. any insight is greatly appreciated on weather i can tighten it or how to go about fixing it.

 

STEERING HEAD BEARINGS:

OEM and aftermarket steering neck or "tube" replacement bearings bring that brand-new feeling back to your bike, improving handling, braking, and steering performance that has been reduced over the year by wear and tear on the bearings and related parts. We offer both the original Ball Bearings and parts for models so equipped, as well as aftermarket Tapered Roller Bearing Kits needed to upgrade this critical area to the most modern design.

Does your bike need new steering head bearings?:

Is this you?:

- "Basically, I am getting a nasty death-wobble at speed on my bike. How can I tell if the steering head bearings are bad? Head shake?"

Here's how to check your steering head bearings:

a) Place the bike on the centerstand, and have a helper sit on the rear of the seat to put the front wheel in the air.

b) Crouch in front of the bike and grab both front forks toward the bottom.

c) Try to "wiggle" the forks fore and aft; there should be no play.

d) With the wheel still elevated, slowly turn the handlebars lock-to-lock. You should feel no binding, looseness, or "bumpity-bumping" in the bars while turning; it should be free and smooth.

e) From a completely centered position, give the handlebars a gentle push to one side. It should fall to full lock smoothly, without binding. Return the bars to straight (centered) and repeat this test in the other direction. If there is a "detent" or looseness at the center, you probably need new bearings

f) If your steering (forks) "lock" in the centered position, and take a good amount of pressure to get them off of the centered position, then your steering head bearings are either over-torqued, or, more likely, worn out.


NOTE: the factory service interval for the re-packing of the steering head bearings with grease is every 10,000 miles (all XJ550, XJ650, XJ750, and XJ1100 models) and every 16,000 miles on the XJ700 and XJ900RK models. The bearings should be inspected every 2,500 - 4,000 miles for looseness, and adjusted as necessary.

NOTE: all 1992-98 XJ600 Seca II, XJ700, XJ750-X, XJ750RL, XJ900, XJ1100, and all XS1100 models used tapered roller bearings originally; all other XJ models used ball bearings from the factory.

NOTE2: always use a high-quality, waterproof grease when installing any style of steering neck bearings!

 

Most likely the head bearing,
The first thing to check...put the bike on the center stand and lift the front wheel off the ground (I usually have my kid sit on the back...could use a weight...or tie downs), and just move the handle bars from lock to lock...Do you feel a "notch" near the center, or is there any restriction/friction going from lock to lock? Next thing is grab the front wheel and vigorously push and pull the wheel front to back and then side to side, again feeling for any play.
The only maintenance you can do is grease the bearings and adjust the headset...IMO it's just as much work to just replace the headset with a roller bearing set up which is far superior.....gotta remember, that grease has been in there for nearly 30 years. It's a labor intensive job but not difficult at all. My only problem is I tend to pile on the work...because if I'm going to all the trouble to do this, I may as well do...this and this and this........

 

Ha Ha! Len....you're too quick for me!

 

Loose swing arm bushings or bearings will also cause a serious speed wobble

 

Thanks everyone ill be testing it tomorrow.

 

Update: I check and it has no play just seems to be loose from side to side how would I tighten it?

 

Which bearing?

 

Steering head bearing and to clarify what side to side means. I ment from lock to lock when only the back wheel is on the ground it will just fall from straightforward to one side

 

It's supposed to do that. You should be able to center the bars and it will hold position until you give it a nudge with one finger, then it should flop to one side.

My advice. Rare is the owner that does maintenance. Assume that the headstock bearings have never been touched. Tear the headsotck down for inspection. Look for notches in the bearing races and worn or rusty bearings. If you find no damage then repack and reinstall. Roller bearings are a good upgrade, and worth the money in my opinion, but are not necessary if the original bearings and races are in serviceable condition.

Be very careful to not lose any of the loose bearings. A towel and a magnet are good helpers here, particularly for the lower bearings.

 

I've upgraded to an All Balls set of roller bearings and it wasn't too difficult. Probably the most annoying part is getting the old races out of the frame and the bottom bearing off the stem. It's definitely worth spending the time and money if you're still running the original bearings.