Classic & Vintage - Lower gears on racer, compact crank or new freewheel?

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schaefere
10-01-11, 02:50 PM
I recently purchased an 85 Bianchi Stelvio with all campy components. I want to get some lower gears on it but not sure what the easiest/cheapest option would be. I'd like to be able to use the same shifters and derailleurs.
Would it be possible to put a triple on the front with the derailleur I have now, or would I only be able to use a compact double?
Could I get a wider range 6 speed freewheel on the back?
Which of these options would give me a wider gear range?
Thanks
grinningfool
10-01-11, 03:05 PM
You could install a megarange freewheel with a 34 tooth granny, which would most likely require a long cage rear derailleur. Putting a triple crankset on is possible, and if you get used components it can be done without breaking the bank. You'll need a longer bottom bracket spindle, a triple front derailleur, and possibly a long cage rear. It can get costly unless you are patient and resourceful at finding used parts.
due ruote
10-01-11, 03:09 PM
http://www.sheldonbrown.com/gears/
Play around with this to figure out your best combinations.
The least expensive option would be a new freewheel. I'm going to guess that you could get a 7 speed to work on that. I hear the Sunrace ones are decent, and don't cost much. Or go with a Shimano. Someone will be along to advise whether that RD can handle a 28 tooth cog, or you can look it up on Velobase.
Puget Pounder
10-01-11, 03:13 PM
Basic breakdown: Anyone can feel free to disagree.
A larger range freewheel is the cheaper option, but means larger gaps between gears. You would need a new freewheel, chain, and a MTB derailleur (if >28 teeth).
A compact crank would require a new crank and bottom bracket (most likely). You would find yourself shifting much on the front to achieve the right combo.
A Triple would require a new crank, bottom bracket, rear derailleur, and front derailleur. Most expensive option, but gives the best options for gears.
jimmuller
10-01-11, 03:51 PM
Ask yourself what you are willing to give up. Your top gear or two? Tight spacing between the gears you use most of the time? Shifting simplicity?
For me years ago that question was easy - the top gears, because I (almost) never used them, never really needed them. But then, I don't mind less tight gear spacing either because I'm not racing anyone so I don't mind if a gear isn't exactly precisely perfectly what I want. As someone said, the cheapest way to get low gears is probably a freewheel. The best way though may be a compact double crank.
Which that's just my opinion, now ain't it?
I do not know how much lower you want to go. In my opinion the triple option should always be looked at first.(unless you have Campy which you do) The triple gives you 5 or 6 more gears.(although you might only use 1 or 2) A third granny ring & new FD with your current freewheel and RD might be enough of a change. But if it is not then you might go to a 28T freewheel before you have to change the RD. The problem is that crank will probably not accept a very small 3rd ring. So no triple for you unless you change the crank as well.
Listen to what jimmuller is saying. What do you want to give up? There is always a tradeoff. Putting a bigger freewheel and long cage RD on the back is probably the cheapest way. But then you might not have as tight of spacing as you are looking for. Look at your where you ride and the riding that you do the most. Then make your decision.
What do you have now -- 52-42 / 13-15-17-19-21-23? (That was stock on my Bianchi.)
Simply replacing a standard (non-ultra) 13-23 6-speed w/ a 13-26 7-speed (been there ... done that) will give you a noticeably lower bottom gear w/o compromising anything else. I ended up gearing my Bianchi 50-42 / 14-16-18-20-23-26, for a superb 1.5-step progression from 43.6 to 96, which meets my needs well. I kept the original derailleurs and could have kept the original crankset, which I replaced w/ a newer Ofmega/Bianchi crankset which can take a 38T inner ring, should I ever need to drop down another 10%.
A case in point is my 72 Lejeune. When I acquired it it had a 52/40 cottered crank on it and a 14-28 5 speed freewheel. The Simplex FD was cracked and I was going to upgrade to cotterless anyway so I acquired a 52/40/32 triple crank/chainrings, a FD that would handle a triple, and another spindle. Put it on and found out for my everyday riding I could go to some smaller cogs on the back. So I acquired 2 more freewheels on ebay for around $15 each. A 14-24 and a 13-21. Now I have the 24 on for my everyday riding. If I'm doing a flatland century the 13-21 goes on. If it is some loaded touring or really hilly riding the 14-28 goes back on. I can take the wheel off, replace the freewheel and have the wheel back on in about 5 minutes. Same chain, RD and best of all tight gear spacing. It works for me.
Of course if you get a modern bike it will have all the range you need. But where is the fun in that?
schaefere
10-02-11, 03:24 AM
Thanks for all the helpful info. Right now it looks like the easiest thing to do is get a 13-28 or 14-28 freewheel, no new RD required. I don't really mind losing the close spacing between gears. Could I simply replace the inner chainring with a smaller one?
Road Fan
10-02-11, 05:02 AM
I'd suggest trying something cheap to get some experience and better learn what you specifically need. In the $25 range, Ebay has a lot of 13-28 7-speed freewheels by Shimano or Falcon, which should just screw right on to your hub. Guessing that what you have there is a 13-21 or 23, a 13-28 would drop your lowest gear ratio by around 30%, which is a huge difference. It would be enough to let you see if you like the new riding experience, and to assess the need for a triple. Plus, with a racing chainset like that, it's very likely your Campy derailleur can actually handle that new freewheel with no problem.
If you buy it at a shop and have them install it, they should also address any issues with chain length as well. It could need to be adjusted. It would cost more at a local shop, but you should come out good to go.
On that chainset you probably can't get a smaller chainwheel. Most that look like that had a bolt circle diameter of 144 mm, and 40 teeth is about the smallest that can be fit in that case. To avoid the much bigger cost of changing the chainset, do the freewheel first to see if it gives you everything you need.
jimmuller
10-02-11, 06:40 AM
Right now it looks like the easiest thing to do is get a 13-28 or 14-28 freewheel, no new RD required.
One thing no one has mentioned is the possible need for a few more links in your chain. You shouldn't be running a big-big combination anyway but we don't know how well you chain length was done in the first place.
devinfan
10-02-11, 06:43 AM
Thanks for all the helpful info. Right now it looks like the easiest thing to do is get a 13-28 or 14-28 freewheel, no new RD required. I don't really mind losing the close spacing between gears. Could I simply replace the inner chainring with a smaller one?
I think you've got the smallest possible ring on there already, looking at your crank, but I might be wrong. John E's suggestion is the easiest and would work best for you, I think. OR...
Since you just purchased the bike, you're not really dialed in to it's range of gears yet. Maybe it's been awhile since you've been on a bike? If that's the case (I'm not saying it is) I would ride for a couple of weeks and go on some longer training/fun/distance rides with some hills. You might find it's your legs and cardio that get upgraded, and that's absolutely free!
Oh yeah - really nice bike, by the way!
THEJAPINO
10-02-11, 11:50 AM
I used to have a regular 53/39 double on one bike and switching to a compact 50/34 double did exactly what I needed. The trade off? I lose one high gear and gain two low gears. To me, that was a perfect compromise. I didn't use my high gear for very long but almost always used my low gear.
LeicaLad
10-02-11, 01:46 PM
There's excellent advice here, but given your desire to keep costs down I think you've seen the best 1st step: a new freewheel.
Go to Niagara or Harris Cyclery (online). Either the Sunrace (very cheap) or Shimano (still quite inexpensive). 28t as the largest cog, as anything bigger will require a derailleur change. This may be all you need, but you should tell us about your hills!
You may need a new chain or some links. Again, not big money. Start with a freewheel. Stay away from large ring/large cog combo and see if the chain is adequate. If not, a new $10 chain will do.
With a 144 bcd crank, such as yours, the smallest available inner ring is 41t. Not worth the money, even if you get the TA or other non-Campy version. You have a 42t now.
The advice about getting out and riding a bit is the best advice.
Do report back to us!
Cheers!
schaefere
10-02-11, 02:01 PM
Well the consensus seems to be get a new freewheel with 28 teeth. That sounds good to me, the price fits too. I don't plan on using the big/big combo, but I have an extra chain laying around that I could salvage extra links from if needed. I've been using a mountain bike with some city slicker tires for some time now, and it just wasn't high enough for the downhills and I never used the small ring. If anyone knows about Golden, CO they know the foothills can be steep, and I just can't do Lookout Mt or Golden Gate Canyon with this gearing.
I think I'll just go for the freewheel and if its not low enough, I'll just have to work on those legs!
Thanks! :thumb:
jimmuller
10-02-11, 05:50 PM
I don't plan on using the big/big combo, but I have an extra chain laying around that I could salvage extra links from if needed.
I keep my bikes set up to accommodate the extreme combinations if necessary. I intend never to use them but every now and then I'll lose track of which cog I'm on, or just shift the front without thinking. Dumb moves do happen when you (which is to say, I) are tired enough.
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