Whips and Chains
[[image:whip_mini.jpg::inline:1]]I have come to the conclusion that some bicycle specific tools are designed to be used on new, or almost new bicycles.
Published June 11, 2007 by C.I.C.L.E.
Contributed by Harv :: Photos by Josef
[[image:whip_inside1.jpg::inline:0]]I have come to the conclusion that some bicycle specific tools are designed to be used on new, or almost new bicycles. Bicycles that have been in use for only a short time, and have not been subject to weathering, corrosion, poor assembly, extreme abuse, or neglect. This is fine for local bike shop mechanics who are preparing new bikes for sale, swapping components to suit a customer, or 'tuning up' a bike that a customer purchased only three months prior.
But after a number of years, that same bike would likely have various fasteners and components with overtorqued, seized, or nearly seized threaded interfaces. Now the mechanic's problem is to separate these parts so a repair or replacement can be effected. There are many such problem areas such as lock rings, bottom bracket fixed cups, freewheels, and pedals. Here we are going to examine the task of removing a stubborn cassette lock ring.
In particular, let's look at the standard 'Chain Whip' tool supplied by all the bike tool specialists. To remove a cassette lock ring, the cassette must be prevented from turning counter-clockwise as the lock ring tool is turned. This is usually done by holding the cassette with a chain whip. A standard chain whip has two major faults in this regard. First, it is too short to develop enough torque. Second, the free end of the short piece of bicycle chain can slip or fall off the cog while in use.
After a couple of these frustrating and time-consuming lock-ring removal sessions at the Bike Oven, I decided a chain-whip redesign was in order. What I came up with is a much longer tool with a closed loop of chain instead of the free length of chain whipping in the breeze and falling off at the slightest opportunity. Actually, this new configuration of tool would not be a 'chain whip', it would be more of a cog wrench.
Now, this is not a general purpose tool. It is designed to fit a limited range of cog sizes, in this case 14 to 16 tooth. You will additionally need a conventional chain whip to do cassette disassembly, or for cassettes that use the smallest cog to lock the assembly onto the free hub. But for the single purpose of removing a Shimano style lockring from a cassette containing a cog in the range of 14 to 16 tooth, this tool and a lock ring remover turned by a 1/2 inch drive socket and ratchet wrench (or breaker bar) will do the job.
Our new, improved tool is made from a piece of aluminum bar stock one and a quarter inches wide and an eighth of an inch thick. You will need about 18 inches of this bar stock which is a standard hardware store item. You will need a piece of bicycle chain 17 pitches long, or eight and a half inches from end bushing center to the opposite end bushing center. Optionally, you can vary the length of the chain to accommodate a different range of cog teeth. The piece of chain is held to the bar stock with 6-32 hardware consisting of two 3/4 inch bolts, four washers and four nuts. Fasten both ends of the chain, forming a loop, to the bar stock, boring clearance holes on 1/2 inch centers. Two nuts for each bolt are locked against each other allowing the chain to pivot freely. Two washers are placed between the chain and the bar stock to allow clearance for the protruding side plates and pins. Slip a length of mountain bike innertube over the end of the bar stock for a cushioned handle.
Orient the tools as indicated in the photo. The gripped cog should have a chain roller on each tooth. Rotate and position the cog tool so that no slack exists before applying torque to the cassette. This setup can save the day when you encounter a difficult lock ring removal due to overtorquing and/or seizing.