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Discussion Starter · #1 ·
When I spin my front wheel and tire on my dirt bike, I can swear that I see a "lump" or "high spot" in the tire. And, maybe it's just in my head, but I can swear that I feel it on road. This got me thinking either the tire is bad and/or the wheel isn't true. A couple of questions.

1. Is it possible the problem is just in the tire? Or, is it more likely the issue is the wheel, which is causing the "high spot" on the tire?

2. What is the best way to true this wheel or check for trueness without a wheel stand. Can I do this with the wheel on the bike?

3. Do I need to take the tire off or can I leave it on? I've read that sometimes, a spoked wheel can be trued without the tire and then when a tire is installed (and air put in) it can lose its trueness.
 

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Ace Tuner
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When I spin my front wheel and tire on my dirt bike, I can swear that I see a "lump" or "high spot" in the tire. And, maybe it's just in my head, but I can swear that I feel it on road. This got me thinking either the tire is bad and/or the wheel isn't true. A couple of questions.

1. Is it possible the problem is just in the tire? Or, is it more likely the issue is the wheel, which is causing the "high spot"
on the tire?

1) Possible it is only the tire but not at all likely. BTW, that is called "hop".

2. What is the best way to true this wheel or check for trueness without a wheel stand. Can I do this with the wheel on the bike?

2) If it is WAY OUT OF TRUE you could probably see it just by getting the tire off the ground and spinning it while eyeballing the wheel/tire assembly, but the best way is to remove the wheel so.....
Without a truing stand you can slide the axle thru the wheel bearings and rest each end of the axle on chairs, cinder blocks or whatever.
Position a long-ish screwdriver (resting on a third chair/block and pointing to the flat inside area where the tire bead would be) so that as you spin the wheel you can watch for "hop" as the wheel turns.
The max out of true spec is usually no more than about .040" out. Where I went to school it was no more than .020" out.
You'd be surprised how easy it is to see .020"~.040" with nothing but a screwdriver and the naked eye.

You can check for side to side true the same way but with the screwdriver 'pointing' to the outside edge of the rim.

3. Do I need to take the tire off or can I leave it on? I've read that sometimes, a spoked wheel can be trued without the tire and then when a tire is installed (and air put in) it can lose its trueness.

3) To check for hop you will need to remove the tire.
If the spokes are tight enough installing the tire will not change anything.
Answers in bold above.

Also note:
You did not say how old the bike is. Older spokes are almost always rusted making truing and torquing correctly a real problem if not impossible without replacing all of the spokes.
 

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You can leave the wheel on the bike, if you can lift it off the ground and clamp a pointer to the forks that nearly touches the rim. It helps to tie off the handlebar, to keep them from turning. As the wheel rotates, lightly tap each fork; properly set, they will all play nearly the same note, but any clunks or higher pitched notes indicate loose or over-tight spokes. If the pointer nearly touches at the corner of the rim, where it turns from the tire bead to the spoke area, you can see both the motions, or you can try setting up two, one parallel to the spokes, the other straight into the rim. Before attempting to adjust the tension, make sure you soak all the spoke nuts with a good penetrating oil overnight, to give it a chance to loosen the threads. Then try to loosen all of them a little, so you don't snap one. The rest is tediously going around, tighten/loosen to take out the wobble, and get them all the same tension. If the rim is actually bent, no amount of adjusting will correct it. They make torque wrenches for spokes, but knowing how much torque is proper is a problem, especially with old spokes.
 

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Check to see that the tire is properly seated at the bead all the way around, on both sides. A tire mounted at a dealership is no guarantee the tire is properly mounted on the wheel. A friend of mine had new tires mounted on his Softail. He came over and was telling me how he could feel something wasn't right. We discovered the rear tire was not properly seated at the bead. The dealer fixed at no cost when the error was pointed out to them.
 

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Discussion Starter · #5 ·
Check to see that the tire is properly seated at the bead all the way around, on both sides. A tire mounted at a dealership is no guarantee the tire is properly mounted on the wheel. A friend of mine had new tires mounted on his Softail. He came over and was telling me how he could feel something wasn't right. We discovered the rear tire was not properly seated at the bead. The dealer fixed at no cost when the error was pointed out to them.
I checked both sides of the tire and the bead seems evently and properly seated, all the way around, and on both side.

The rim and tire are new. But, it is out of trueness. I did a rudimentary check this afternoon. I will rig up a better test later, but from what I can see, it's out of trueness.
 
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