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Discussion Starter · #1 ·
A buddy of mine and I started riding recreationally last year. I caught the bug harder then he did and two bikes later I have a light 10 speed. My buddy is still pushing a 20 year old 6 speed. He has alot of trouble with the inclines (not long or steep hills). I looked at his bike and he has a Shimano 600 drivetrain with a 52/42 front and a 25T as his biggest cog in the back. Will the Shimano 600 FD work with a 39 inner ring? If not can a 105 FD be installed on a bike with down tube shifters? Are there 6 or possibly 7 speed cassettes or free wheel available that would have a bigger gear. I am not sure whether it is a freewheel or freehub.

He doesn't want to spend alot because this will be a temporary fix. If his work picks up he is getting a new bike and if not he hopefully will get in better shape.
 

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Joe the biker said:
A buddy of mine and I started riding recreationally last year. I caught the bug harder then he did and two bikes later I have a light 10 speed. My buddy is still pushing a 20 year old 6 speed. He has alot of trouble with the inclines (not long or steep hills). I looked at his bike and he has a Shimano 600 drivetrain with a 52/42 front and a 25T as his biggest cog in the back. Will the Shimano 600 FD work with a 39 inner ring? If not can a 105 FD be installed on a bike with down tube shifters? Are there 6 or possibly 7 speed cassettes or free wheel available that would have a bigger gear. I am not sure whether it is a freewheel or freehub.

He doesn't want to spend alot because this will be a temporary fix. If his work picks up he is getting a new bike and if not he hopefully will get in better shape.
Simple and cheap: They have these in both 6 and 7. Look at the Megarange if he REALLY needs a low gear.

http://www.sheldonbrown.com/harris/freewheels.html#7
 

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My 84 Ciocc came with a Shimano 600.

I had no problems flying up hills in the 42t little ring, and that was on a 21-12 7-speed cassette. But I'm a little past the recreational rider.

Now I upgraded (I use that term loosely) to an 8-speed Shimano Sora 52-39 on the 600 FD. It will work, but watch the trim on that 600. Sometimes the chain can pop off when dropping into that little ring. If memory serves me correct, the 600 crank uses the same BCD as the Sora. 130mm.

Also what cassette is he running? I upgraded to a 9-speed setup and ran a 25-11 on my 600 and the 4-tooth increase helped me off the line and up hills.
 

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Joe the biker said:
A buddy of mine and I started riding recreationally last year. I caught the bug harder then he did and two bikes later I have a light 10 speed. My buddy is still pushing a 20 year old 6 speed. He has alot of trouble with the inclines (not long or steep hills). I looked at his bike and he has a Shimano 600 drivetrain with a 52/42 front and a 25T as his biggest cog in the back. Will the Shimano 600 FD work with a 39 inner ring? If not can a 105 FD be installed on a bike with down tube shifters? Are there 6 or possibly 7 speed cassettes or free wheel available that would have a bigger gear. I am not sure whether it is a freewheel or freehub.

He doesn't want to spend alot because this will be a temporary fix. If his work picks up he is getting a new bike and if not he hopefully will get in better shape.
Just buy a cheap 39 tooth ring for the crank. Derailleur should be designed to handle it just fine.

Yes, a 105 derailleur will work with DT shifters, no problem. It'll actually work better because you can trim a friction DT shifter. You can't do that (as well) with STI.

And yes, there are cheap freewheels out there that will work. Nashbar usually carries them. Avoid the mega-range stuff, though. His rear derailleur will probably max out on a 26 or 27 tooth freewheel.

Figure if you have the tools and know what yer doing, you could make these changes for less than $50. If you've got to go to yer LBS, figure $100. Either way, pretty cheap.
 

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avoid the Megarange, the 600 rear derailleur is good for a max of 27 teeth.

most 600-equipped frames didn't have more than 25t on them.
 

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second that

OES said:
Simple and cheap: They have these in both 6 and 7. Look at the Megarange if he REALLY needs a low gear.

http://www.sheldonbrown.com/harris/freewheels.html#7
If it's a 20-year-old 6-speed, it's a freewheel, and probably will fit a 7-speed freewheel. For 20 bucks he can get a 7-speed with a 28, which would lower his lowest gear about 11%; changing the 42 ring to a 39 (another $20 for a cheap ring) would lower it only about 7% (changing both would lower it about 17%). He might need a new (longer) chain, which he probably needs anyway. Front deralleur should work; the only issue might be the rear derailleur handling the extra wrap, but you can probably make it work with the 28. The megarange with the 34 is more iffy.
 

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Discussion Starter · #7 ·
Thanks

Considering that this is supposed to be a short term fix I think that changing the cluster to a 7 speed with a 28T top gear will give the most bang for the buck. I told him to call the bike shop to get a price. They can figure out the chain and RD compatibility issues better than we can. The only problem is if he goes into the shop he will probably walk out with a new $4,000 carbon bike that he can't afford right now. Not my problem though. Except then I may have to upgrade to keep up.
 

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Joe the biker said:
Considering that this is supposed to be a short term fix I think that changing the cluster to a 7 speed with a 28T top gear will give the most bang for the buck. I told him to call the bike shop to get a price. They can figure out the chain and RD compatibility issues better than we can. The only problem is if he goes into the shop he will probably walk out with a new $4,000 carbon bike that he can't afford right now. Not my problem though. Except then I may have to upgrade to keep up.
I was being quick and cryptic, so I forgot to mention what other folks kindly and correctly pointed out: A megarange will take a long cage rear derailleur, which still could be done on the cheap. Even a real cheap damn derailleur works great for normal applications. It's mature technology.

The 600 RD should handle 28 with no sweat though, in fact I'm sure it will, and that IS probably the cheapest and best fix unless that's still not low enough to get him up the hill, which is entirely possible for a new rider, and no embarrassment.
 

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Nope

buck-50 said:
Just buy a cheap 39 tooth ring for the crank. Derailleur should be designed to handle it just fine.
It is extremely likely that the crank is sized so that the smallest chainring it will take is a 42. You probably can't just swap in a 39.
 
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