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. 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. Do you need to replace an older, threaded rear hub to update to a modern, index-shifting drivetrain?

FH-7850 and FH-7900 Dura-Ace bodies, which have returned to a splined attachment between Freehub body and hub shell, but it is larger than the usual one. It is similar but not interchangeable between these two models. Shimano information on the 7850; 7900. Not all 8-speed cassettes are compatible. Campagnolo and Shimano 8-speed cassettes have different spacing, so it is generally not possible to achieve proper indexing when combining a Campagnolo 8-speed wheel with a Shimano shift system, or vice versa. 3. Is a cassette better than a freewheel tool? Uniglide cassettes are no longer available. If you have a hub that only uses Uniglide cassettes, the best thing to do is to upgrade the hub by transplanting a Hyperglide body onto it. The same procedure works for off-brand Freehubs that have a LH threaded fastener accessed from the LH side of the hub, too. It doesn't work with freehub bodies that screw directly into the hub shell. Leave the freewheel in place on the wheel, or screw it onto a wheel, so that you will have something to hold it with. Breaking the freewheel loose from the wheel now with a freewheel remover reduces the likelihood of damage to the inner body if you have to remove it for reassembly. (If you don't have the right freewheel remover, or the remover splines on the freewheel are munged up, it is useful last resort to grab the inner body in a vise to remove it, after disassembling the freewheel.)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 A freewheel that has been ridden for a long time, especially by a strong rider with low gears, may be quite difficult to remove because the threads are so tight.

Sheldon's advice makes very good sense for Shimano Freehub bodies, because they are common, and easily replaced. But these days, more surviving freewheels are cherished antiques. Rebuilding them doesn't deserve to be a lost art. Here is how to rebuild one. I (John Allen) especially like old SunTour freewheels, and I use them as examples in this article. Freewheels of other brands are basically the same, but differ in detail. Ultra Six ®" spaced 6 speeds used a closer spacing, around 5 mm. This permitted an Ultra Six ® freewheel to directly replace a standard 5-speed unit on a 120 mm hub. The key to making this work was the use of a narrower chain. The interior width of the chain was the same as always, but the new narrower chains used shorter rivets, so the ends of the rivets didn't protrude past the outer chain plates, as the rivets in traditional chains did. Hold the bicycle with the rear wheel off the ground, and leaning to the left at about a 45 degree angle. An assistant may be helpful for this. Turn the pedals around a couple of times to get the wheel spinning fast, then let it coast (helps to be in high gear for this.) Triplizer (adaptor) chainrings for 130mm BCD area available from Spa cycles, but IIRC a record ace will have a 144mm BCD chainset in which case a 'red clover' triplizer might be the only off the shelf option.In reality, the fancier parts aren't always the most suitable, in the same way that a Ferrari, while it is a great racecar, isn't at all as good for daily transportation as a Toyota -- there are practical issues of cost, reliability, serviceability and durability. With bicycle components, the performance gain with higher-end models is often minuscule. Remember, you account for 80 percent of the weight even if you are riding a rather heavy bicycle! you don't need to buy the spacer, because you can use the spacer that came between the original flat 13 and the 14.) 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? Shimano lists Freehub bodies as a separate part, or you could cannibalize a hub. Wheels with damaged rims and good hubs are not hard to find.

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. An additional complication is that "road" front derailer cages are shaped to fit well with a 52-53 tooth big chainring, while most current "mountain" front cages are shaped to fit with a 42-44 tooth big ring. The earliest Shimano Freehubs, however, used a more primitive construction. There was a set of splines to keep the body from rotating on the hub shell, but instead of a hollow bolt to secure the body to the shell, there was a smooth cylindrical projection past the splines, and the corresponding Freehub body was a slip fit over this projection. The axle held the assembly from falling off, but the design was not fully satisfactory. The Freehub body could burnish the projecting sleeve, and loosen.Shimano Freehubs dating from the mid 1980s onward have replaceable bodies, held onto the hub shell by screw threads and, usually, splines. This is explained above in the transplant section of this article. 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.

A 38/39 will give you a gear similar to a 32, this was a common route to take in the era of your bike.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. 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. Narrow chains bring other problems, though. They are usually more expensive and -- with 10 or more speeds -- don't last as long -- even when used in the intended system. 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! In practice this "problem" almost never materializes. Many, many cyclists are using 9- and 10-speed chains with older cranksets and having no problems whatever. New Chainrings, Old ChainsGoing the other direction, using wider chains with chainrings intended for narrower chains is not generally a major problem if there's only a one- or two- generation difference. The only problem you might run into is that the chain will be more liable to rub on the inside of the bigger chainrings in the small/small crossover gears, gears you shouldn't be using in any case.