[ziominix]

Are their actual torque specs for tightening the steering head bearing?? I think I've over tightened it, it seemed loose before.

Here's the full story.

Ok, I've got a front end wobble that hasn't gone away after alignment, balancing th etire, and then replacing the tire. I was thinking it could be a bent rim. I've read to check the steering head bearing by taking the front end off the ground and checking the full movement of the bars, side to side, for roughness. Well no roughness. Then today I spoke with what seemed to be a very knowledgeable guy at a kawasaki place on the phone, and he said all of the above, and also to check for tightness of the bearing by letting the wheel fall to the stop, and if it fell quickly, it probably needed tightened. Well low and behold, it seemed to fall to the right side fast, and hit the stop. It had some resistance going to the left, as there is a cable that begins to snug slightly around the top part of the tube, above the forks.

So, I took off the cap, and went to tighten the bearing, and it was loose, as in it was easily tightened with minimal effort. So i tightened it down quite snugly.

This however only changed the range of my problem. I used to have a wobble/shake, from 45 to 36 ish, now it shakes all the way down to the mid/low 20's.


So how tight is that thing supposed to be? And how do I know if I should lubricate it, and with what??

I'm planning on heading to DC tomorrow with my dad and grandpa, the ride to the wall. About a 6 or 7 hour trip, so I want to make sure everything is perfect before heading out.

 

[dwengi]

Bearings should be cleaned and lubricated with wheel bearing grease.

The nut that loads the bearings is torqued to 65 INCH LBS. Then tighten down the locknut without allowing the primary nut to rotate further.

The big chrome bolt on the top of the triple clamp is torqued to 35 ft-lbs.

 

[ziominix]

Ok, the big chrome one, the one right in the center of the handlebars with a black cap on it, right?

Thats the one I've been screwing with, as it wasn't very tight to begin with.

 

[fog]

Forgive me, but you alignment is incorrect.

FOG

 

[ziominix]

Well, I've spent alot of time measuring and remeasuring, and I really thought it was dead on. Guess I should try again.

Is 35 ft lbs as quoted above correct though?


I guess I'm out to set up some strings again.

 

[dwengi]

As far as your shimmy is concerned you need to be more concerned with the nut that is loading the head bearings under the triple clamp. Tightening the big chrome bolt will not load the bearings.

Fog is probably right that the shimmy is the result of alignment - but get the bearing preload right first.

 

[fog]

Ok on the bearing adjustin nut the preload is nery low and hand tight will cover it, not play of loosness but free movment. The 35 Lbs refers to the cap nut after the top triple clamp.

FOG

 

[dad]

Tightening the big chrome bolt will not load the bearings.

In theory, not. In practice though, it actually does. ??? This is what makes that such a wierd set-up and generally doesn't need or want any more than finger tight on the bearing adjuster nut. You want a pre-load on those bearings but not a great amount. Just enough to prevent free-play in the final assembly and under load.

As you draw the top tree retainer bolt down it takes the small amount of clearance existing in the bearing adjuster nut threads that is loaded in the extended direction and pushes it down in the compressed direction. It therefore adds load directly by the stretch in the head bolt that is added from that movement. The added load is a sizeable amount and if any measurable torque is applied initially, the final bolt tightening will likely end up with the bearings grossly overloaded and will displace the grease at the contact points and flat spot them in a very short time. Think about, sketch it if you have to, but it's true, and you'll see it. The final bolt tightening will generally add all of the pre-load you want when the first nut is just fingertight. Good luck.

 

[fog]

Like I said.

FOG

 

[dad]

Like I said.

FOG

Yup. 8) I was just trying to 'splain it in all of it's glorious detail. How it actually does add bearing load when you tighten the top tree bolt.

 

[ziominix]

Well, darn, I need some pictures apparently. So the big chrome bolt does not need 35lbs, so I overtightened it, as I did crank it to 35 lbs. Is that going to screw anything up, I only rode about 3 minutes with it like that. So the chrome one needs to be tightened just by hand, not with a torque wrench. Got it. Where exactly is the "cap nut at the top of the tripple clamp", and what all do I need to take apart to get at it?

Also, while riding with the visor up on my helmet at low speeds while test riding, I can hear a continuous, rhythmic catching noise coming from up front. Could a warped rotor cause such issues???


Thanks

Ashley

 

[jlmay]

define "catching noise".

 

[dad]

NO! You absolutely DO tighten the chrome bolt. It's the spanner nut UNDER the top triple tree that does not get tightened more than finger tight. That's the round nut with notches in it for a special socket to engage.

And yes, that rythmic noise could be the rotor but if it is, it should quit making the noise when the front brake is applied.

 

[ziominix]

Ok, directly below the triple tree, thats where I get at the bolt that needs to be just finger tight right? So is this directly above the horn assembly? Cause thats what I see directly mounted below the triple tree.

 

[dwengi]

Remove the triple tree and there it is.

 

[dad]

NO! You absolutely DO tighten the chrome bolt. It's the spanner nut UNDER the top triple tree that does not get tightened more than finger tight. That's the round nut with notches in it for a special socket to engage.

No, the horn is below the bottom triple tree and bolted to the frame. The top tree is held by the chrome bolt. Directly underneath the top tree is the spanner style nut that gets finger tightened on the steering stem, setting the bearing tension. If this isn't clear, get somebody to look at it with you who understands this. It's too important to experiment with.

 

[bitzz]

To add flame to the fire....

The manual states the stem locknut (the bottom one in the stack) is torqued to 39 N-m or 29 ft/lbs. A little more than finger tight.
The subsequent nuts are to lock the stem nut in place and if set correctly cannot and will not effect the loading of the bearings.
These specs are for the OEM balls and races. Don't use them on aftermarket taper bearings.

 

[fog]

To add flame to the fire....

The manual states the stem locknut (the bottom one in the stack) is torqued to 39 N-m or 29 ft/lbs. A little more than finger tight.
The subsequent nuts are to lock the stem nut in place and if set correctly cannot and will not effect the loading of the bearings.
These specs are for the OEM balls and races. Don't use them on aftermarket taper bearings.

Aw Bitz, comon, 29 ft. lbs. is a hell of a lot more than finger tight, and it refers to the chrome cap nut on the top of the top triple.

FOG

 

[dad]

The subsequent nuts are to lock the stem nut in place and if set correctly cannot and will not effect the loading of the bearings.

Where does the couple of thousandths clearance in the adjuster nut thread go when you tighten the top tree bolt at a higher torque than the bearing adjuster nut? That's where the additional bearing pre-load occurs, that thread clearance being taken out, shifted to the opposite side of the thread. Sketch it for yourself if you don't see it. It's there.

I've been down this road with other bikes doing it by the book, including using the spring scale at the bar end to read the drag, and a snug fingertight on the nut is then reduced by the thread clearance in that nut, making the bearing setting tighter as the top bolt is tightened. After screwing with one for quite some time I came back to the set-up I described and is the way I do it on all bikes now. If the bearings are new, tighten once to be sure the races are seated and then back off, finger tighten snug, and the additional pre-load from the shift in the thread clearance gets the pre-load just about right. This is actually a very flaky set-up and is also common to most, if not all bikes.