jpsawyer

I know some people that say to leave the tire and tube on when truing a wheel and some that say to take it all off. I normally take the tire and tube off when I true wheels. But just wondering if it is necessary or beneficial to take the tire and tube off or to leave them on and what you guys do.

hueyhoolihan

i can't see any harm in leaving them off or any benefit in leaving them on. i've even read on the "touring" forum of those who leave their clothes on when in the shower. so i guess it means... well i don't know what it means.

Drew Eckhardt 

It'd be hard to see radial run-out with a tire installed.

ThermionicScott 

I think the thinking is that you might puncture the rim tape and tube by turning the spokes with a tire on.

Drew Eckhardt 

The rim tape and tube aren't anywhere near the spokes/nipples in a double wall rim and some multiple of the .018" of spoke movement produced by a full turn of a nipple isn't going to do anything in a single wall rim.

Darth_Firebolt

someone on here (maybe psimet?) measured a significant spoke tension drop when the tire is installed and inflated. if you true a wheel, a lot of the time it will not stay when you inflate the tire. to skip that step, i just true my wheels with the tires on and inflated.

Stealthammer

I alway remove the tire if I'm not just tightening a loose spoke. I often find the radial run-out on wheels that I haven't trued before is not as close as I would prefer, and the extra weight of the tire makes spinning the wheel a hassle, especially on MTB wheels.

Stannian

But the nipple tears through the rim strip, then the tube, or leaves the nipple exposed to eventually wear a hole in the tube. One turn typically doesn't cause a problem though, and you can just deflate the tire to prevent it.

As far as checking round, yes, take the tire off.

hagen2456

It's a lot easier do do a decent job if you take'em off. In particular if you don't have a truing stand and will have to use the fork/chanstays.

mrrabbit 

1. Easier to do a quality job with tires off.
2. With tires off, you get an excellent view of the brake pads - makes "perfect" pad alignment much easier.
3. With tires off, you get a much more accurate view of the wheel alignment in the rear and front dropouts and stays.

=8-)

fietsbob

Touch-up tensioning and truing on a stand, in new bike pre sales prep.
just getting things to the last half mm
or major repair wheel well out of good true shape ?

pdlamb

The only time I've seen a trued wheel lose true when I started winding was when I had significant spoke wind-up. Heard the wheel pinging as I started pedaling. Wind up can happen either way.

I take the lazy way; if there's a minor blip, or one spoke loose or broken, leave the tire on. If I've waited too long and the whole wheel is wonky, take the tire off, loosen everything, and start (almost) over.

neurocop

Yep...that is the main reason to remove the tire. The second is so that you can see if the spokes are sticking too far through the nipples.

pat5319

You only NEED to remove the tire on a single walled rim as rotation of the nipple can damage the rim strip as it has contact to it and can even damage the tube as well. I will sometimes remove the tire on my wheels even though most are double walled as as I can check for roundness as well as trueness, and it is a bit easier to be precise.

spathfinder3408

I have trued a lot of wheels and would not take a tire off if the wheel was off a little bit and could be corrected easily if it was a rim off to the right or left. If the wheel has a bump to it the tire has to come off to remove that. Sometimes you can never get a wheel trued because a rim has had impact to it and is actually bent. time for a new rim.

Al1943

It really depends on the wheel. With light weight road rims there is a significant difference in spoke tension with the tire fully inflated as compared to deflated. I have measured a difference of 5 to 7% in spoke tension, and the change in spoke tension does effect the lateral true and dish slightly, about 1/2 mm. When building a wheel I get it as true as possible radially and laterally before mounting the tire and tube. After mounting and inflating I check the wheel again and make whatever adjustments needed in tension, truing, and dishing to make the wheel more accurate at riding pressure. On a rear wheel this usually means tightening the non-drive side spokes slightly to center the rim. My rims are Mavic Open Pro and DT Swiss road rims. YMMV

jpsawyer

Thanks everyone. All the info is greatly appreciated. I also use Mavic Open Pros so next time I end up needing to true one, hopefully not too soon, I will do what you do. I wouldn't have thought there would be that much difference in spoke tension with a fully inflated tire mounted.
thanks