Are you sure? I have taken apart many Shimano 600 and Dura-Ace hubs, and I have only seen what is shown in the picture in the 2nd generation Dura-Ace hubs. I think that with 600 Shimano went directly from the first-generation press-fit body to the 3rd generation 10mm hollow bolt.

I have upgraded several older 600 Uniglide-style hubs to Hyperglide freehubs. No issues.

I have also upgraded several of the first-generation 600 press-fit hubs to 8/9/10 speed Hyperglide freehubs, without using the hollow fixing bolt. Bolt really isn't needed as the hub axle and cones holds everything together.

Interesting topic.

I have the same problem with the old style 600 hubs that have a screw on last cog.

Now as others mention just buy a 5/6 speed pignon remove the cogs and handfile the biggest spline to fit.

No problem there and use the spacers.

So so good,but what if one doesn't have the last screw on cog to secure the rest.

Is there an alternative to get.

As mentioned, a BB lockring can be substituted for the last cog.
I'd advise against that... it won't be as strong, that's for sure. Probably a pretty bad idea if you weigh more than 80kg, I'm guessing.

Good news, HG freewheel nut and casette on 600 hub installed. After study of many shimano docsheets, i went around a nice bicycle shop where they gave me an whole old mtb rear wheel for free :o (what a nice experience.. it was dirty as hell :D, but.. otherwise they would throw it away..) The hub which i robbed was FHRM40 hub with a Y-3SL98030 fw body. (there is more options as i learned from docsheets, but this one run across, so..) I tought that newermind its 8cog body, i would have room for spacers to adjust it to index shifting, but then, installed chain, and what a surprise, its working with old indexed 600ex shifter without any change on new HG casette. It has similar sound like on my old MTB bike (i could robb the 7cog hub from that bike than i realised.. but no way, that one should stay intact :D)

..dont care about the gap between 28T (last cog) and spokes.. thats ok, the chain is not jumping inbetween.. There is now still place for 8th cog if i choose to.. (than with friction shifting).
here it is: http://bikeforums.net/attachment.php...hmentid=261958

..only thing that bothers me, is that the hub body is now abit to the left (because of 8cog fw body), so the spokes on the right (by dishing) would be maybe too straight to the rim? Hmm..

Yes, you will have very bad dish with that configuration. I would remove about 5-8mm of axle spacers from the right and put on left side to centre the hub. Configure so that smallest cog is 3.5-4.0mm away from the dropout inner face. The chain should barely clear the dropout. This reduces dish to a minimum and gives you the strongest wheel possible.

Excellent!, thank you, that should help! ((did work.. won some mm also by replacing spacer on freewheel body.. and the lockring still locks the casette..)) Thx all for your help.