I have been wanting a wider range freewheel for my bike. I went looking for a Suntour Ultra-6 freewheel in 13-34T configuration.

OMG!, they are selling for $200 - $300 on ebay, so that is the end of that idea.

What can be done to modify the gearing on a 120 mm rear triangle? Do I need to buy a new wheel? Is there any way to retrofit more modern gearing (cassette?) onto a freewheel hub?

It helps to know what kind of bike and what frame material you have. Any method of installing modern wide-range gearing inexpensively will involve widening the rear triangle for a modern cassette hub.

The reborn Sun XCD hubs are available in 120mm width: Hubs ? SunXCD - Bicycle Components but I'm not sure they're available. The 130mm width are already pricey: SunXCD Large Flange Rear Cassette Hub

Triplizer or triple crank. Otherwise the gear jumps of a wide range freewheel are too drastic.

Do you have indexed or friction shifting?

Freqently you can squeeze 7 speed freewheels onto your hub with only minor mods.

DNP Epoch makes an 11-32, 7 speed freewheel:
DNP Epoch Freewheel 7spd 11-32 Nickel Plated

It does have a pretty big jump up to the 32 though.
Freewheel Cogs: 11,13,15,18,21,24,32

One thing about the DNP freewheels is that they have lot of back spacing, so they may be problematic.

With the 11T, you can go to smaller chainrings if you desire.

Also consider the Shimano MegaRange freewheels (although with big jumps).

Not sure what you are trying to accomplish. But IRD makes freewheels. Probably the least painless method. IIRC they are in the ~$50 range.

Aaron

Check with Mike Kone at Compass. He sent out an email about having a bunch of new freewheels. I don't remember the brand, but I think he mentioned some 14-28 ranges and an $88 price tag.

If you have a good 5-speed SunTour freewheel body, you can probably find larger low gear cogs for it on eBay and perhaps around here. (I might still have some unused 32 or 34T cogs on my pegboard -- I'll check). Then, with a couple of chain whips or a chain whip and a freewheel clamp for your bench vise, you can swap cogs as desired. Pastor Bob may be able to help.

I can help. [MENTION=348240]Bad Lag[/MENTION] send me a PM.

if you can get by with a 28t on the rear with your current double, get a new ird fw for $50 or sunrace fw for under $20.

i like ird, 'cause they're stealthy quiet and probably a little nicer in quality and long-term dependability.

Are they selling for that much or just listed for that much? I picked up a new-ish SunTour Winner Pro 6-speed 13-34 for $50 not too long ago. I can't remember whether it was here on the big auction site. You might want to place a WTB ad in our for sale section here.

And like Bill says above, a Sunrace HG copy is dirt cheap and shifts great.

I'm sure pastor bob will set you up, but in case he doesn't have what you're looking for, pm me. I've got a couple of unused alpha 6, and should be able to build one up to the gearing you're looking for.

I had a bike with 120 rear spacing that I wanted a wider range on. I just laced an used Shimano 126 7 speed cassette hub onto my wheel. The flange dimensions were the same as the Malliard hub it replaced so I was able to use the spokes over again. Seven speed cassettes are widely available and the 12-32ish cassettes from SRAM and Shimano are not expensive or hard to find. They don't have that ugly jump to the 34 like the Shimano megarange freewheels do. A 126 wheel will slide right into a 120 spaced frame with a negligible amount of fuss.

Yes.

Oh, I thought you said free wheels.

Good point.

Check the SOLD listings on E-Bay.

There are often quite a few buy-it-now listings on E-Bay that are wishful thinking. Also check Amazon and other sources.

The IRD freewheels look pretty but the 5-speeds spacing... that 14-16-20 sequence on the 14-28 looks jarring, so does the 24-32 shift on the 13-32. I suppose the 17 cog they have is for the wrong position and they have no 26 cog.

The 7-speeds look ok, though. The 7x13-28 and 13-32 are the same gearing as a Shimano 8-speed cassettes but without the 11t

I've put 6s freewheels onto many old 120mm hubs with only having to move a ~1.5mm washer from the non-driveside end of the axle to the driveside end of the axle. An extra washer would expand the selection of 120mm hubs that this "trick" would work on, while only increasing the axle spacing by a mm or two.
But every bike is different, and spacings and clearances need to be well-considered, tested and re-corrected if necessary.

When I re-dish the wheel to restore centering of the rim, I typically increase and equalize the spoke tensions, so the wheel is still as strong as it was.
Axle re-spacing efforts are time consuming I must admit. I tend to try to optimize the wheel and axle strength by lengthening the driveside axle spacing by the most minimal amount, hence the added consumption of time as I may need to "home in" on exact dimensional adjustments.

On bikes with wide-ranging chainring sizes, such as 52-36t, I am able to ride fast enough using only a 13-24t five-speed freewheel even here in the foothills.
But with more-normal chainring sizes, I need at least six cogs to handle the terrain changes and keep up with today's local pelotons.

Lastly, a typical Shimano 7s, 126mm freehub can be narrowed to about 122mm simply by removing washers from both ends of the axle.
And on many bikes, there will still be enough clearance for the chain at the dropout.
Here's a 124mm-spaced 7s, freewheel-style wheel I put together for use in a 121mm Peugeot frame. This wheel is strong as heck!

Anyone looking for vintage freewheels can not possibly buy a freewheel that shifts as well as a modern new IRD Classica freewheel. I don't care what anyone says and I know people love group correct kit. I've seen 'em all. Suntour, Shimao, Sachs freewheels, Atoms, Campagnolo, Cyclo, Everest, Maillard, Regina etc.

All were good freewheels, even great in their day, but nothing on par to the high bar that IRD has now set with the Classica freewheels. Simply put you can't buy another freewheel of the same quality with the same shifting precision. I don't care what your eBay budget is. Modern crappy Shimano freewheels come close to the quality in the shifting performance, but not quite. Vintage high end freewheels like Suntour come close in the quality category, but don't have the shifting ramps.

End of story, the golden age of the freewheel in terms of performance is actually now:

Classica Freewheels 5/6/7-Speed ? Interloc Racing Design / IRD

^ cool. i had not seen those 'classica' freewheels before. very posh.

Those look nice, but I wish they made a close-range six speed for us flatlanders; something like a 14-21. I almost never need anything lower than a 21 tooth cog, I'm not going to cross-chain from the 42 ring to a 13, and I certainly can't push a 53 x 13 gear.

As far as I know, no modern freewheels have such an option.

Ok we'll end the story if you like, but I don't believe much of what you just wrote myself.

The IRD freewheels sound good, but don't quite have Shimano's years and miles of cumulative reputation at this point.

I have no idea if the design or quality is copied from the 600 freewheels (which were never offered in 7 speed). My Giang freewheel from 8 or 9 years ago (Giang has long been IRD's and American Classic's freewheel/cassette supplier) looks about like what is being sold today, but I wouldn't say that it shifts quite as well as the equivalent Shimano 13-28t freewheel. It's been ok, that's all, but does look very good and has smooth bearings.

They say:
"That's because all the big Asian manufacturers are only churning out freewheels for department store bikes. We made these purposely nice enough to put on a vintage Cinelli road bike, but affordable enough to use as a replacement on cheaper bikes with. The Classic takes design cues from the reliable Shimano 600 series."

Actually, they don't make these at all. Last I heard, they have them made in Malaysia by, you guessed it, a "big Asian manufacturer". I have a problem with the common practice of, for instance, food being sold where the labeling only tells the buyer who the distributor is, so as to camouflage that the candy you buy is made in Mexico, or that the fish you buy is pulled out of polluted waters in China. I don't even want to buy any food that is made in China, since a country's food supply is a primary matter of national security. And I don't want to pretend that anything else that is being entirely sourced out is made here in the US.

I'm happy to see that IRD have persisted with their freewheel offerings. The 13-24t five-speed sounds awesome, but some (like the 13-28t six-speed) seem to have ratio sequencing (13-15-18...) that I would find maddening while trying to ride with a fast group, though I guess that I have to admit that Sunrace and Shimano don't even offer a 13-28t six speed any more (Shimano once made some really good ones).
Since I mostly friction shift, I prefer still building up my own 5, 6 and 7s Uniglide freewheels, which seem to offer just the right amount of audible feedback to assure robust transmission under hard-riding conditions.

I have to say I am still "blown away" by Sunrace's introduction of their 7s 13-25t freewheel, a combination of ratios that I was no longer able to source reliably. I'll post a picture of one (below the picture of the Giang 13-28t).

I'm posting some large pictures here, so sorry if this doesn't agree with everyone's device display!

How does it feel jumping to a 34 on a six speed, and did you use a MTB derialleur to fit that size?

I have a build coming, and I'd like to use that ratio for climbing adventures.

Well, it feels normal to me, since I've been doing it since I got back into cycling about 5 years ago. And yes, usually I will employ a "mountain bike" RD to do this, or rather anything with a long cage, including vintage Shimano 600 (both Arabesque and 6200 series), Crane, SunTour Cyclone (three different generations), SunTour aRX, VG-T, Blue Line, Shimano Tourney, 105, etc...

It's a good way to avoid the extra hassles of going to a triple up front (which I also do a lot, because I like to tinker.)

But it doesn't necessarily take a triple or a long-cage RD. Here's my Super Course in a previous configuration running a 34 cog with an Arabesque short cage RD. With the exactly right combo of chain length, RD hanger length, and position in the dropout, it worked just fine.

A lot of IRD's freewheel and cassette sequences bug me, but it might be unfair to complain as I'm not a current customer. Even though they provide the wider ranges they claim are more in demand, the jumps are uneven in most combinations. It's too bad they don't sell the cogs individually, since they're making them anyway.

That may all be true, but will the IRD index correctly with Accushift? I was under the impression that they wouldn't, due to Suntour's irregular spacing change in the bottom two cogs.

Here's a Sachs freewheel on the local Craigslist.

Sachs Maillard 6 speed Freewheel---New Old Stock - $30 (NE Eugene)

6 spd:
13-15-17-21-26-32



You don't quite get the 34 you wanted, but it is pretty big.

I could probably snag it and drop it in the mail, if the seller isn't wanting to ship.