Wheel "dish" measurement for KTM 300?

[JG2]

Does anyone out there know the correct measurement for wheel "dish" on a 300XC front & rear wheels?

I bought a truing stand, "trued" the heck out of my front rim and suddenly realized I had failed to consider wheel dish. I loosened and tightened a lot of spokes trying to get it totally true and the rim runs nice & straight but but now one side of my front rim is further from the hub than the other.

A completely dumbass thing to do.

I'm worried I pulled my front rim too far over and am wondering if anyone out there knows the exact measurements for the dish on 300 wheels? I have poked around on Google but have not found an answer from anyone who really seems to know. Lots of generic "just center it and don't worry about it" type comments but I have OCD and want to set it back to KTM spec.

I appreciate the help guys - thanks in advance.

[cedric]

Have you mounted the wheel properly in the forks and measured/compared the distance from fork leg to rim edge on each side? If these are equal than I would think your bike will handle properly.

[JG2]

Yes, when I realized what I had done I installed and seated the front wheel properly and did a 1/2 arsed measurement with a ruler to the fork guard to see what it looked like and it's out maybe 5mm. That is admittedly a very poor measurement but I just wanted to see how bad it was. I mounted the tire last night and will re-install the front wheel and try and see how bad it is out.

What is most frustrating about this, other than my failing to check the measurement to begin with, is that the KTM Service Manual is so piss-poor. My old Honda manual had the specific dish measurements and how to obtain them in the manual, easy as pie. KTM manuals really suck.

Does anyone out there have 1) new KTM and 2) time on their hands to measure the distance from the outside of the rotor to the edge of the rim for me?

[Dobi]

Now you have me questioning myself.... I will measure both my homemade warp 9 rims and my new KTM assembled rims in the next night or two and post back. I would assume the measurement from a flat surface would be different for each side due to rotors etc, and could easily see 5mm of deflection from fork guards...

[JG2]

That measurement to fork guards I took was useless, really.

I was thinking that a measurement from the outside surface of the brake rotor (e.g. furthest from the hub) to the rim edge is all I need - I will move my rim over to whatever that distance is.

[Bark]

I'm not an expert but the fork clamps and forks themselves look symmetric. It makes sense that they would be symmetric. So, if you take good quality measurements from your fork tubes (which are 100% machined so good quality surfaces) to your rim you should be equidistant on either side. I would ignore the brake rotor. If you are equidistant +/- 1mm I would think you're pretty good, unless you are highly skilled at this type of measurement which is not easy because there are no flat parallel surfaces in this discussion. Personally, I would make some sort of spacer out of wood/steel/aluminum as a gage to compare left gap to right gap to the rim from the tubes.

[cedric]

Bark is explaining better what I meant in my first post. Find a way to measure/compare the distance between the outside fork tube and the rim on each side, when they are equal (or close enough) you are good to go.

Something like this should work (will allow comparison side to side but won't give absolute numbers....

[AJRJ]

A long straight off of the hub face, measured to the lip of the wheel rim is what I would do.

I would not guarantee that the rim is centered in the forks (to the mm), The preload side is variable, and the forks are always set to operate freely.

[JG2]

I ended up using my caliper to measure from the fork legs to the rim edges and am off center-by roughly 5.25mm. Sigh.

So I need to pull the rim over 2mm or so - probably not that difficult. We will see. (I somehow doubt that I'd even notice the difference while riding, however)

As a side note for anyone who is curious or ever in this same boat, from WARP 9 wheels..."The front should be centered on the hub. You can pull it over while it’s on the bike. Put some zip ties on your fork legs to measure the distance to center, then align it straight."

"The rear should be dished 1-9/16’’ from the brake disc to the rim."

Thanks for all the replies and suggestions - this forum is a great resource and worth the $40 RMDRA membership fee all on it's own.

[axel99]

2.125mm not worth fussing over. I am not sure the centerline of the rim is supose to pass through the middle of the hub in the rotating plane, althought it would make sense. In this case if the wheels are true forget about it. You may be suprised if you measeured the at the amount of "run-out" in the front and rear wheels when mounted on the bike. What about the out of round measurement, is the centerline of the axel in the center of the rim (the distance from the outer edge of the rim to the center of the axel should be the same).

[Dobi]

I laid my rims flat and measured using a digital vernier caliper and a framing square. 2 sets of front and rear rims, one being a handmade pair of warp 9s on factory hubs and the other being stock 16 ktm rims with no rides on them. None of the 4 rims were perfectly centered. they all varied between 2 and 4mm in measurement from the straightedge to the rim.