bikemig 

I'm trying to take apart a TA cyclotourist crank and neither of my chainring nut wrenches work. I don't have a screwdriver that works on these either. I imagine there was once a special nutwrench for the chainring bolts. Will the Park CNW 2 chainring nut wrench work? Is there another solution out there?

https://www.parktool.com/product/cha...t-wrench-cnw-2

3speedslow

I think the last time I took mine apart, I used a suitably large screwdriver to hold the lock bolt.

conspiratemus1

Yeah, it has to be a thick screwdriver with a long handle, good square edges and fully as wide as the slot. Bear down hard on it while you're torquing the hex head on the other side -- clamping the crank/chainring in a vice helps steady it. And it'll still probably jump out on you.
...And, it'll work only for the three that aren't half-hidden under the crank.

Slightspeed

I just bought that Park tool yesterday. It doesn't work very well on my Sugino AT crank. These screws are really stuck. I managed to get two off, but the other three are really stubborn. I just want to change a 50t ring to a 52. Should have been a 10 minute job, I'm into day 2. After two penetrating oil soakings and the new tool, still no go. The tool keeps slipping which screws up the little slots in the back. I've always been able to fake it with a large flat screw driver. Since these were so tight, I thought I'd try the right tool. No joy yet. Good luck with yours.

52telecaster

If and when you get it apart, velo orange sells much better screws for those. I use the velos on a t.a. and an ancient shimano deore 50.4.

bikemig 

Is there a tool designed to work on these chainring bolts? There must be an old tool designed for the TA cyclotourist.

bikemig 

Yeah that did the trick. Rather than use a vice though I mounted the crank arm to the spindle which held it securely. I could have used three hands though so I could use one to hold the crank arm, one for the screwdriver, and the third for wrench, . I used my body to keep the crank arm from spinning and got that sucker out. This is such a nice crank but the chainring bolts are a bit of a bear.

JohnDThompson 

Maybe the #24 "Special key for 5 pins chainwheel bolts?"

I confess I've never seen this tool in the flesh.

bikemig 

I'd love to have that tool bag with all those old tools . . . .

I've never fooled with a TA crankset before. It is a good looking crankset on a vintage bike and chainrings are still available.

John E

Same here.

conspiratemus1

Yes, love that old crank. (Congrats to the OP for getting the nuts off.) They were wonderful for 1970s-style loaded camping-touring. 48T outer, some convenient middle, 26T inner, what's not to like? Rings lasted a long time, still have them. Sadly, pedal broke out of the eye of the left crank during my last year commuting before I retired in '16, just as I stood up to climb an overpass. Ouch that pavement is hard. Fortunately no cars behind me and no injury. (The fractured bits show the usual old surface + new surface appearance so it was likely a fretting crack that propagated into the crank until pop---> splat!)

Salamandrine 

The first shop I worked in had a complete TA case, and we built up TA cranks to suit all the time, yet I don't think we had one of those #24 tools. Maybe we did; it's been a long time.

Chainring bolts freezing shut was always an issue even BITD. I quickly learned to always use generous amounts of grease on them, but not everyone did. 40+ years later, of course there will be even more hassle.

Anyway, I would search for a big screwdriver that fits the slot well, and then square up the end with a grinder or file. Soak well with your favorite penetrant beforehand, and proceed carefully.

Metacortex

The T.A. ref #24 tool is an 8mm nut driver, it is for the older domed style T.A. bolts.

Slightspeed

I just finished getting the chain ring bolts off my Sugino AT with help from my old Workmate's wooden jaws. I clamped the Park tool hard against the messed up nut slots on the back side, and used a 90° angled hex driver on the front. I can usually get by with a large flat blade screw driver, but these were really stuck, so I bought the Park tool. This was a swap meet crankset that I bought 3 years ago, and never needed to remove the rings. I decided to try a 52t in place of the 50. What should have been a 10 minute job took three days, includng a couple of PB Blaster soaks. Turns out the screws were stuck with what looks like red Loctite. Now I need to find new chain ring bolts.

Park tool clamped hard against back side nut.

90°hex driver just cleared crank arm.

Red Loctite evidence?

wesmamyke 

The current VAR chainring nut wrench is really good, it has two slightly different sides. Whenever the Park/Campy/whatever brands don't work that thing always grabs without slipping, one side of it will anyway.

bikemig 

Are you talking about this tool?

https://www.vartools.com/en/chainrin...d-var-p644.php

I may need to order one.

wesmamyke 

Yeah, that's the one. Not sure why it works so good, the ends look pretty normal.

It's a bit longer than any of the standard ones, that might help as much as it fitting better.

JohnDThompson 

I was thinking more like this one (yer comin' out bolt; I don't take "no" for an answer):

https://www.vartools.com/en/combined-tool-for-chainring-bolts-var-p828.php