I thought cone wrenches were cone wrenches. I have a couple of LIFO cone wrenches. Weird cone wrenches in that each end is double cut so one side will work for 15mm and then more recessed for 13mm. The other side is 14mm/16mm.

Well the strange thing is I'm having trouble getting both cone wrenches on the same side of the hub. One on the cone, the other on the outer locknut. Its a 6500 Ultegra front hub. Did cone width narrow or something, or are my old LIFO wrenches just worthless for being too thick?

Shimano locknuts are almost all 17 mm so if your largest wrench is 16 mm, that may explain it.

Try a different brand of cone wrench. I have cone wrenches from VAR, Campagnolo, Hozan, and ATD. Some fit some hubs better than others.

Are you trying to adjust the cone while the wheel is on the bike? I take off the wheel to do the adjustment. This allows me to use a cone wrench on the cone and any wrench, regardless of thickness, on the lock nut. My cone wrench is a Sunlite combination CW, lock ring tool, and chain whip. It's 4mm thick and works great. I use an ordinary adjustable wrench (or any wrench with the correct jaw opening) on the lock nut.

FWIW, I check for proper adjustment by twirling the axle ends while the wheel stands on the floor. I loosen one lock nut and manually tighten the cone until the bearings rumble a bit. It's felt in the fingers. I then back off until the rumbling goes away but I can't feel play in the axle. Then I tighten the lock nut and reinstall the wheel. It pays to check the bearings again by feel after some riding. (I believe this is all per Sheldon Brown.)

Properly adjusted, a mounted front wheel will have zero free play but can be spun manually and continue spinning by itself for a couple of minutes. You'll get tired of waiting for it to stop.

None of these will make any difference if the OP's wrench is too small for the locknut.

Maybe my first post wasn't clear enough. I have the exact size cone wrenches needed. Ultegra 6500 hubs...there isn't enough room to get both cone wrenches on at the same time. The outer locknut can only fit a cone wrench, not a regular wrench. Seems insane my thin cone wrenhes are "too thick."

Agreed, they should fit.

Are they flat wrenches, or do they offset slightly? My older Spin Doctor wrenches had the small/large nut opening thing like these, but would only fit one way on the wheel. They would interfere with each other if one was backwards/upside down. If your wrenches are flat, then it sounds like you'll need to buy thinner ones. I replaced mine with Park double ended ones, a pair of 13/14 and a pair of 15/16.

Not to belabor this, but are you adjusting the cones with the wheel on the bike? If so, please see my previous post. If there is an advantage to doing it with the wheel installed, I'm afraid I don't see it. My lock nuts are also narrow (about 4mm), but it doesn't prevent the use of a thicker wrench.

Since the locknut is outboard, ANY thickness wrench will fit. Remove wheel from bike.

To OP, yes I have had this issue with those cheaper wrenches you find in tool kits. You can lightly grind some of the side of the cone down, if you don't mind the cosmetics.

No. On new and higher end Shimano hubs, particularly this Ultegra hub, the outer locknut has an outside flange. The cone wrench has to fit between the flange and the spacer.

Get a pair of Park wrenches that are the right size. You have a new and improved hub that has the wrench flats adjacent to each other.

Thanks for the correction.

Yep. Pretty tight in there.

https://wheelsmfg.com/tech/PDF/hub/hb-6500.pdf

In emergencies I sometimes just hammer the cone wrenches out after I'm done locking them down. I'm not sure if I should file my wrenches down or just get rid of those wheels with locknuts that have fewer than six flats on 'em

Or maybe I'll just get tiny washers between cones and locknuts. .5mm on each side

OK, 6500 hubs and their contemporary Dura Ace 77000-series hubs did indeed require two cone wrenches as the locknuts had thin flats like the cones. The front hub required a 13 mm cone wrench on the cone and a 14 mm cone wrench for the locknuts while the rear hub required 14 mm cone wrenches for both. I've used Park cone wrenches on my 7700 hubs with no problems. I'm still not sure you don't have an opening width mismatch rather than a thickness issue.

Not the case. The outer locknut on an Ultegra 6500 hub is adjusted with cone wrenches. There is a cone flat on the inside half. If you saw a picture of one you'd understand why the assumption didn't hold.

Thanks! I was assuming both were 13mm. Because the 13 would slide over the cone flat. I wasn't paying attention to whether the locknut was a different size. An oversight on my part. Thank you!

Like the OP, I ran into cone wrenches that were too thick for the flanged locknut on Shimano hubs (XT M760). I think I found that the maximum thickness cone wrench that will fit that locknut is right around 2.0mm.

The thickness of various cone wrenches I have include:

Park DCW: 1.85mm

Park SCW: 2.15mm

Park CW: 2.45mm

Tacx: 2.05mm

Hozan: 2.00mm