speed freewheels with 13-15-17-19-21-24-28 teeth are available from Shimano, SunRace and IRD. This is a nice, even progression, or you may choose another -- see list of available freewheels from Harris Cyclery. Modern freewheels have the same easy-shifting features as cassettes. Within a given brand/style of rear derailer, all "speed numbers" are generally interchangeable. This applies to all indexable models, basically everything manufactured since the late 1980s. There are a few exceptions: you don't need to buy the spacer, because you can use the spacer that came between the original flat 13 and the 14.) Mountain" hubs will likely be slightly better sealed against dirt and mud than "road" hubs, but this is rarely an issue in practice. The wider 135 mm spacing will generally result in a slightly stronger wheel due to reduced dishing of the spokes. Many off-brand "Shimano type" Freehub bodies are not available, if they're even removable. Many of the off-brand hubs have the body riveted onto the hub shell.

Now you thoroughly clean all the parts of the freewheel mechanism. I (John Allen) use solvent followed by a strong solution of dishwashing detergent and a water rinse. I dry the parts afterward with paper towels to prevent rust. Even with a 30T inner chainring (you can go smaller than that, but look out for front derailleur capacity limits) you can use a cheap 14-28 6s or 13-28 7s freewheel to get a low gear like you want. Since chainrings usually last several freewheels/chains, this is not an expensive setup to run, because the freewheels and chains cost little. Freewheel bodies have a larger diameter than the spoking flange of many hubs. Warning: loosen a freewheel before cutting the spokes to replace the rim, otherwise you may not be able to loosen the freewheel or to replace the spokes on the right side of the wheel. The barrel (between the flanges) of many hubs will break if you respoke only the left side and then try to unscrew the freewheel. My 1984 Record Ace now has a triple with 26/36/46 and a 10 freehub with a 32 on the rear.Old age does not come alone!

Shimano 6 speed 14-28T Freewheel and Chain

Standard spaced 6-speeds required increasing the frame spacing to 126 mm, aggravating the problems introduced with the move to 5-speed, but still providing satisfactory service in most cases. Alternately, you can grind a bevel on the ends of the splines of an older body. This is a five-minute job if you have access to a bench grinder. Clean up carefully afterward so particles of metal and grinding-wheel grit don't wear out the bearings. All recent freewheels and threaded hubs, regardless of where made, use ISO threading. The older British and Italian standards use the same thread pitch but a very slightly different thread diameter, and are generally interchangeable. However, for strong riders and on tandems, it is best not to mix and match -- freewheels sometimes do strip the threads of aluminium hubs. A French freewheel may start to thread onto an ISO/British/Italian hub but will soon bind. An ISO/British/Italian freewheel will skim the top of the threads of a French hub and will slip forward if an attempt is made to use it. Do not force a freewheel -- you will ruin the hub. Old Chainrings, New ChainsThere is a lot of confusion about the compatibility of narrow 9- and 10-speed chains with older cranksets. Shimano says you should replace the inner chainring(s) with specially designated 9- or 10-speed ones, but then they're all too eager to sell you stuff, whether you need it or not.

First scrape off as much grit and grime as you can, then flush the old lubricant out of the freewheel before relubricating it, To do this, you will need a parts cleaning bath, preferably with a sprayer. Loosening the outer ring by a couple of turns can create a larger gap into which to spray the cleaning solution. Dura-Ace 7800 and 7801 10-speed hubs (and Ultegra wheelsets) with the aluminum Freehub body and tall splines accept only Dura-Ace, Ultegra and 105 10-speed cassettes. Derailer cage widths differ, but this is most often a concern when replacing pulleys: the bolts may not reach.SpeedsIn the 1980s, these two approaches were combined to create 7-speed freewheels, with 5 mm ("Ultra") spacing that would fit the same 126 mm hubs as "standard" 6-speeds. Early Hyperglide hubs had both external and internal threads, so they would work with either style of cassette. With other freewheels, reassembly can be more difficult. In days of yore, there were special bobby-pin-like clips to hold the pawls compressed against their springs while you re-assembled the freewheel. These are no longer available. Replacement bodies are not available for these early hubs, which can sometimes be identified by the narrow barrel, without the characteristic bulge on the right end. (The bulge is to accommodate the threading for the hollow bolt used on newer Shimano Freehubs) See the photos below, kindly provided by David Landsberg.

Long-cage (SGS) derailers have greater takeup capacity, and work with all types of cassettes. Long-cage derailers are commonly called "mountain" derailers currently, though in the past, this style of derailer was known as a "touring" derailer. (The marketeers retired the use of "touring" as a buzzword in the late '80s when mountain bikes became the hot item.) "Road" vs "Mountain" Front Derailers Campagnolo/Shimano 8-speed cassettes have different spacing , so you can't generally get good indexing using a Campagnolo 8-speed wheel with a Shimano shift system or vice versa.

Yes, SRAM and Shimano 8-speed cassettes are generally interchangeable. If you have either SRAM or Shimano components, you can use cassettes from either brand without compatibility issues, as long as you're not changing the whole groupset. 5. Do freewheels wear out? So my question is does this have a good chance of working or might there be problems? What pitfalls do I need to look out for? I made a spreadsheet of the gear ratios and they look very good. There is no large gap in the lowest 2 gear ratios and the middle gears that I mostly use are also very nicely spaced (between 11 and 14% gap). A 5-speed freewheel or Suntour Ultra-6 will work with the 120 mm rear dropout spacing that was usual in the 1970s. A 7-speed freewheel needs at least 126 mm spacing, but only steel frames are likely to have narrower spacing, and they can usually be cold set to spread the dropouts. You also may need to redish the rear wheel-- see article on frame spacing. To convert to a cassette, you would have to replace the rear wheel. But also, most Uniglide Freehubs can be updated by installing a Hyperglide ratchet body. This is an easy and inexpensive modification (see below.) The foot power is very considerable, and that's why it can be so hard to remove a freewheel that has been used for a while, especially on a bike with low gearing. To prevent future difficulty with removal, it is very important to grease the threads before screwing a freewheel onto your hub!