DMR Single Speed Spacer Kit

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'''And The DMR Kit?'''

In the bag you get spacers, a cassette lockring, and a 16 tooth rear cog. Quality wise the kit is pretty good. The spacers are well made anodised aluminium rings. The rear cog is pressed chrome steel. Not the highest quality but perfectly adequate for it's use. The lockring is made from steel and is perfectly acceptable quality.

Fitting is straightforward. The largest 20mm ring is ...
...was the cassette lockring. The DMR lockring has a bigger diameter than a standard cassette lockring, and so is perfect for use with the spacers.

'''Overall'''

If you are lucky this kit will work straight out of the bag. But you could find yourself having to shell out for extra kit, and like me it would have payed you to source everything separately. Shame because quality wise there is nothing wrong with it.  ... more

The Company

Design Make Ride is a British company. Begun in 1995 they focus on the more extreme side of mountain biking. BSX, slalom, 4X, jumping and freestyle.

To Single Speed Or Not To Single Speed

Single speeds, and their track equivalent fixies, have seen a resurgence in the last couple of years. Single speeds are about as retro as you can get. Your dad, or more likely your granddad would have ridden a single speed bike.

So Why Single Speed?

Fitness. Climbing hills on a single speed requires commitment from the rider. You can't just slip your bike into a lazy gear, you have to go for it. This either means standing up on the pedals to deliver power at low pedal speeds, or remain sitting down and use high cadence (high pedal speed) to reach the top. Single speeding will make big improvements in your fitness. You have to get fit to make it to the top of any hills.

It's cool, especially if you have built your own single speeder. I'm often asked questions about my bike by fellow passengers on the train, and is a good way to make friends.

Simplicity. Removing the gears, removes a whole bunch of stuff, which will either break or go wrong. Removing the derailleur also reduces friction, and improves efficiency of the transmission.

How to Single Speed

Take off the gears, gear levers, surplus front chainrings, and rear cassette. Put spacer rings and single speed cog onto rear freehub, add a chain tensioner if needed, slap on single speed chain, set chainline, and ride away.

Well it's not quite that easy. You have to check the dropouts to see if you need a tensioner. If your bike has horizontal dropouts (slots for the wheel), then you don't need a tensioner. However most geared bikes have vertical dropouts, and so will need a tensioner to keep the chain taut. For general use a sprung tensioner is probably best. Getting the chainline right is critical for any single speed bike. The chain should run in a dead straight line from the front chainring to the rear cog. The further off the chainline, the more likely you are to get problems. A poorly adjusted chainline can cause serious accidents. Face planting yourself in the tarmac because your chain has skipped off the back cog isn't funny.

And The DMR Kit?

In the bag you get spacers, a cassette lockring, and a 16 tooth rear cog. Quality wise the kit is pretty good. The spacers are well made anodised aluminium rings. The rear cog is pressed chrome steel. Not the highest quality but perfectly adequate for it's use. The lockring is made from steel and is perfectly acceptable quality.

Fitting is straightforward. The largest 20mm ring is placed on first, and the remaining rings are then used to set the chainline. Unfortunately I found that with the combination of spacers supplied I was unable to set the chainline quite right. The kit would have been better if the 20mm ring was cut either in half or in a 8mm/12mm split. In the end I bought another spacer kit, which had a better spread of spacer ring widths.

The typical standard for off-road is a 32 tooth front with a 16 tooth rear, and a 42 front with a 16 tooth rear for use on road, so a 16 tooth cog is a sensible choice for the kit. Unfortunately I had a 44 tooth front chainring, and found the 16 tooth cog geared my bike a tad too high. So I also changed the rear cog for an 18 tooth. Other spacer kits have both a 16 and an 18 tooth rear cog, giving better flexibility. In the end the only thing I kept out of the original kit was the cassette lockring. The DMR lockring has a bigger diameter than a standard cassette lockring, and so is perfect for use with the spacers.

Overall

If you are lucky this kit will work straight out of the bag. But you could find yourself having to shell out for extra kit, and like me it would have payed you to source everything separately. Shame because quality wise there is nothing wrong with it. 

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