More Wrench Twirling

Here's the original front tire from my WR-250R with 5,000 miles on it.
See how the knobs of the tread rubber are all slanted toward the back?
That's normal wear from heavy front brake use on pavement.
It's worn to the point that it needs to be replaced, so let's get the show on the road, shall we?





First thing is to get the bike up on my stand and then unbolt the front brake caliper.
Doesn't that 270mm Brembo brake rotor look all purdy? :)





Yes, people.
This is what a Kayaba (aka KYB) front fork looks like with the wheel removed.
To get the wheel off, it required removing the brake caliper, loosening the axle pinch bolts at the very bottom of the fork, removing the axle nut on the brake rotor side, pulling out the axle, and rolling the wheel away.
Simple design.
That's just how I'd a' done it.





Time to play with the tire irons and my spray bottle of Fantastik.
Changing a tire ain't my favorite thing to do, but since it has to be done from time-to-time, I had to learn how to do it for myself.
I haven't pinched a tube (put a hole in the tube with the tire irons) in years, either.
*knocks wood* :)





Do you know what this is?
This be the thing most people call the wheel spacer.
The Yamaha parts catalogue calls it a collar, so that's what I'll call it.
Hey, I read those catalogues all day, so why not, eh?
Notice how the side that goes into the wheel hub seal looks all greasy.
That's important stuff, and the reason being is that the seals for the wheel bearings require grease on them in order to function properly.
You see, the grease helps them seal and lubricates them so they don't wear out in a blink of an eye.
And you know what happens when the seals get worn out, don'cha'?
Ever have a buddy who always seems to be replacing his wheel bearings?
I'll bet you a Red Bull that he doesn't know about this and puts his wheel collars back into the seals dry and without grease on them (nor on the wheel axle, itself).
Maybe he even lets the collars roll around on the ground getting all dirty and just puts them back in the seals with a ton of dirt on them.
Yeah, that sounds like a really cool thing to do, Lenny.
Now, you can straighten him out on this subject and keep all the credit for yourself.
That's OK with me - I know the real score, Buckwheat. :)





Here are the axle pinch bolts at the bottom of the fork leg.
These get a cleaning and a bit of grease on the threads, too.
No, they won't loosen because of the grease.
The grease keeps them from getting what's called galled.
Galling is when harsh metal-to-metal contact wears and deforms the metal, and the big ape twisting the wrench forces it to turn anyway and then damages the threads.
This is what happens when your lazy buddy's chain adjuster bolts seize in the swingarm and he can't turn them anymore.
You know what happens if the threads in that fork leg get wrecked to the point that the bolt won't go in there?
Yeah, Bucky, you'll be faced with either trying to repair it, or buying a new fork leg.
I bet that ain't cheap.
I betcha' that money would buy a lot of Doritos.
Nacho cheese flavor, please.





Behold the front wheel axle.
This very important part gets a cleaning, and then the majority of it's length get a thin smearing of that good ol' grease.
Because of the grease, it won't corrode in place or be difficult to remove next time as well as prevent any water and dirt from getting into the wheel.
This is what wears those bearing out before they should:
Dirt and water getting in there.
The dirt and water belongs on the outside of your wheel hub, people. :)
Ever see your buddy having to pound the shit out of his axle in order to get it to come out?
Well, guess what he ain't doing.
The larger-diameter part I'm holding it by doesn't get the grease because this is where the right-hand side fork leg pinches around it, and we want a clean, metal-to-metal clamping action at that spot when we tighten those axle pinch bolts.





Yeeeaaahhhh.
Another dab of grease for the axle threads.
Some guys think this is a strange thing to do - lubricating your wheel axle threads.
Those are the guys with the galled axle threads and under-torqued axle nuts because some of the torque put into tightening their nuts (that sounds funny, doesn't it? :) ) is actually spent in overcoming the friction from their axle threads that are getting all messed-up.
Yeah, that's right, Sunshine.
Now you know.





All buttoned-up and ready to romp.
And I did take it for a good romp yesterday evening from about 6:00pm-8:20pm, riding past sunset into dusk.
It felt great, too, and the new front tire felt wonderful.
Any questions?


-John