cpsqlrwn

I am looking at a bike right now that has Shimano 600EX group and includes the 6208 rear derailleur. I have several questions. Derailleur and rear hub is pictured at the bottom of this post. I apologize in advance if some of these questions are a little off the deep end. I guess I know enough to be dangerous. Thank you in advance for any assistance.

1) I am curious about the shifting functionality and indexing performance of this derailleur, being that it is the first generation of Shimano 600 that had indexing capability. Does it do a good job of indexing or does it leave a lot to be desired?

2) This bike I am considering is a 6-speed with a 13-28 Shimano freewheel. Will this derailleur handle 7 speed freewheels in both friction and indexed mode or only in friction mode or not at all? See next question as well regarding this subject.

3) Is it possible to have a 6 speed indexed rear derailleur with a 7 speed freewheel that will work 7 gears in friction mode and will work 6 gears in indexed mode because that is all the shifting capability it has for indexed? If so, can the system be adjusted so that the 6 indexed gears are the 6 smallest tooth cogs (leaving out the largest cog)?

4) The existing freewheel is a Shimano 13-28 freewheel. What options do I have to continue to use a 6-speed freewheel but with a 12 tooth cog and a tight span, say 12-18 or 12-19 or 12-21? It appears as though Shimano does not make a 6-speed freewheel with a 12 cog. Are there other brands that would work and give me a 12 tooth cog? The rear hub is Campy so I am thinking maybe a Sachs would work. Does that seem likely? Picture also attached of the hub.

Thanks for any info!!!

Bianchigirll 

Interesting B tension screw.

I think a 12T on a 6spd FW might be hard to find.

The shifter will only index 6 speeds, but will handle 7 or even 8 in frictions.

I believe these shifters were subject to the 'teeth' breaking off the index pod or whatever shipmano called it, it is in the upper right in the pic



In this pic the 'teeth' are broken off

cpsqlrwn

Thanks for the post, Bianchigirll. That's really not a good look. Can any others confirm this please?

Classtime 

The teeth broke off on mine too. I replaced the shifters with 7 speed shifters and used a 7 speed FW for super shifting with that same derailleur. Is that a Trek 560?

rccardr 

Bill- That RD will happily shift a 6-7-8-9-10 speed cassette of up to 28 teeth when paired with the appropriate indexing shifter. 6208 shifters are somewhat fragile and it is not unusual to find only a couple of tangs remaining of the original six on the indexing pod. Not to worry, ANY Shimano indexing shifter is compatible with a 6208 RD. Aside from the fragile shifter tangs, 6207/6208 components are very robust...in fact 6207 shifters are my fave friction units.

I have 6208 on my 86 Ironman and late 80's Peter Mooney. Very nice stuff.
To answer your questions in order:
See above.
No, friction only.
No, friction only.
No 12 tooth small Shimano freewheel cogs, I'm afraid. At least as far as I know. Sachs made some 7 speed freewheels with 12 tooth small cogs (have one on the Botty), some others prolly did as well. But the Sachs spacing is the same as Shimano for indexing.

JohnDThompson 

Yes, that was a weakness of those shifters. You used to be able to buy the indexing pod separately, and it was interchangeable between 6 and 7-speed, Dura-Ace and 600, so you could convert a 6-speed model 600 lever set to 7-speed simply by swapping out the indexing pod with either a 600 or Dura-Ace 7-speed pod.

dddd

6-Speed SIS derailers should not be used with indexed 8, 9 or 10s shifters of any type.

The shift to the largest cog will not index quite right. It's not an issue of the derailer's travel limits, but that the actuation ratio does not remain linear, so there will be hesitation and/or noise when trying to use the largest cog.

crank_addict

Suggest to first review the Sutherlands book. You must also consider the frame dropout, axle length spacers, etc. for handling a 12t cog. Shifters need to be precise fresh and not worn. Lot of rough junk being peddled on the auction site.

Possibilities for index but it really helps to have an arsenal of used freewheel and parts to experiment with. Twist tooth to profiled freewheel cogs are desired but if you must, standard cogs may suffice and then select appropriate thickness cog spacers.

Realize you're seeking a tight ratio and with 12t, consider Sachs LY series or Regina freewheels CX or CX-s with 12t. Alternative spacers for Regina exist but you really need to do some resourceful work and find the right narrow chain. Its been awhile but did experiment with some narrow spacers and fit 7 cogs with 12/13 combo on the end of a CX body. Also, spacers can easily be custom machined. Crazy enough, fitted to a 120 width space on a 1st gen Dura Ace hub. I should look in my odd lot pile again but decided to run a 6 speed on that build.

That derailleur can handle quite a bit and with some mods. I'll look at a few bikes again but had partially ground down the stops which gave more range. Cages can be swapped with XT though requires pivot bolt mods. Jockey pulley type and chains largely matter too. Again, it requires time experimenting and a mix of parts on hand.

rccardr 

Mmmmmm.
Agreed in principle with regard to non linear actuation ratio, but in actual use on several installations, I've not experienced difficulties of any kind. And I'm quite fussy about shifting quality.
On the other hand, I use DT shifters almost exclusively, so STI's or bar ends may result in messier shifts to the larger cogs.

Jeff Wills

Shimano never made a 6-speed freewheel that would accept a 12-tooth small cog. If you wanted a 12, the 7-speed Santé and Dura-Ace freewheels were the way to go.

I'm pretty sure the SunTour New Winner regular spacing 6-speed (not Ultra) would go to 12-tooth (and 11-tooth, for that matter). Those cogs were very rare back then, nearly impossible to find now, and the result would not be index-compatible anyway.

How about a Regina Extra? I'm pretty sure it's not index-compatible but you won't know until you try: https://www.ebay.com/itm/183920531218