Front end trouble shooting

[Rickrod3]

My bike has a slight tendency to want to dip to the left.
once @ high speed around 90mph it started to wobble.
I'm going to go though the front soon as per the manual specs. Based on the experiance of the collective what would be some things to pay attention to.
I have reliable history on the bike and can say with certainty that it has never crashed.
I just recently installed a Tkat fork brace. so those two bases are coverd.
For the most part its no problem I mostly ride between 45 and 75 bike is stable for the most part athe these speeds.

thanks in advance
Rick

[DiverRay]

Start with the steering stem bearings! Plan on replacement, but you MAY be able to lube them. After that, check the REAR suspension, as it can also cause problems. If you have one bad shock, the swingarm on the bike WILL tweak, and you WILL notice it.
If I was going in that far, I would do the forks as well. new oil and seals(Yamaha), and possibly new springs. Don't forget to look at the front tire closely, as it may cause some of the problems.
Biggest thing is putting the front end together properly. With the front tire off the ground, start from the top down on the bolts. Snug them all at first, and then go back and tighten them from top to bottom. The fender and fork brace will need to be loose as well, with the fork brace the LAST thing to be put on and tightened.

[crazy steve]

This post (http://www.xs11.com/forum/showthread...fork+alignment) has a link to an alignment procedure that's always worked for me.

Also check everything for straightness; don't assume anything. While you have the forks off and disassembled, check for smooth, easy sliding of the inner tube in the fork lower; any binding is a problem and needs to be fixed. Make sure your steering head bearings are good and tightened properly. And make sure the rear swingarm/wheel is aligned/adjusted as per the factory specs, as problems there can 'telegraph' and make you think the problem is in the front.

Check for uneven tire wear; this can be either a symptom or a cause. Look at the wheel bearings. If you're running a windshield or fairing, sometime wind turbulance can cause problems; does it go away with that removed?

[Rickrod3]

Tire wear

Steve funny you should mention uneven tire wear.



I recently replaced front and rear tires they had 10K on them
The front wore less inside the green area all around the tire. I was thinking it is cause of the dual compound. Is it something that requires attention?

Thanks for the tips and I'll read the tread on fastening up the front end.

[crazy steve]

Uneven tire wear can be caused by all sorts of issues; low pressure, misalignment in the forks, out of balance, even a defective tire. If you replaced the tires and the same problem remained, then you can probably rule the tire out.

One good thing about removing/rebuilding the forks; checking all these things becomes fairly simple. Trying to chase this with the parts on the bike can become frustrating...

[Ken Talbot]

...Make sure your steering head bearings are good and tightened properly....

This means only 7.2 to 8.7 ft-lbs on the big castellated nut, which is not much more than finger tight. Most people tend to over tighten it because they just don't believe how little it needs, and they can't stick their torque wrench on it to measure it. To see how little this is, clamp a bolt in a bench vise, use an light inch-lbs wrench set for 96 inch-lbs, and pull till your wrench clicks. Do this a few times to get a feel for it, then torque the castellated nut to the same feel whhile it is fresh in your memory.

[crazy steve]

There is another method to adjust the steering head bearings with no torque wrench needed, and that's the 'fall-away' method.

To do this, support the bike with the front wheel off the ground. It's best if the clutch/throttle cables are disconnected at the bars (or just remove the bars) so they don't influence the results.

With the front wheel pointing straight ahead, gently nudge it one way or the other until it 'falls away'. When the bearings are right, you should be able to move the front edge of the wheel between 1/2"-1" before it 'falls'. Less than 1/2", they're too loose. More than 1", they're too tight. Be sure and check both directions. I'll note that dry or damaged bearings will give false readings, so make sure yours are in good shape before using this method. This has always worked for me....