Is it a fixie or singlespeed?

Singlespeed or multispeed chain for cheap singlespeed conversion?

• I'm doing a really cheap and simple singlespeed conversion to an old MTB to use for uni. I'm going to get rid of the dérailleurs front and back, then put on a new chain. I'll have the chain the right length to be tensioned on one gear with the horizonal dropouts. So the 7-speed cassette and the triple up front will still be there, but the shorter chain will only be running on one gear front and back. Should I go for a singlespeed chain or a multispeed chain (both in 3/32" width, of course)? Pros and cons that I can see for choosing a singlespeed chain: Pros: *Won't be so keen to 'ghost shift' *Cheaper (though not by a great deal) *When I have the money to change the crank/chainwheel (it's a riveted chainset at the moment, so I can't take the granny + middle ring off) and rear hub (it's a conventional threaded freewheel, so I would have trouble with dishing and chainline if I just stuck a BMX sprocket on there), the singlespeed chain will be better-compatible. Cons: *Chainline might not be great, in which case a singlespeed chain might get fussy and be noisy *It runs on a multispeed chain at the moment, IIABDFI. Has anyone done a similar thing, or got the expertise to help me out? Thanks Ben

• Answer:

  In my humble opinion, after building many single speed and fixed wheel bikes, the most important thing will be chain line. A good chain line will mean that the transmission will be smooth and quiet with less chance of ghost shifting. To achieve this end (and assuming a 3 clanger of 23,38 and 48 teeth) the 48 tooth chain wheel would probably run best over the 14 or 16 sprockets. This would give a gear of about 80+ inches. Even on the flat this is a large gear. Might be better to use the 38 tooth chain wheel with a straight chain running to the 18 tooth sprocket. If this is a viable option you would have a gear of about 55 inches. A bit low, but good for in town traffic and some hills. The granny ring would run over the 28 tooth sprocket giving a gear of 27 inches. Far too low for road use. So, chain line is very important. As for what chain to use, I would suggest that it will all be down to personal choice. I normally use 1/8" chains but in my off road single speeds I use 3/32" in order that a spare can be obtained at any cycle shop. Multi speed or whatever. I doubt you will notice ant difference. The chain line can be altered slightly by using a different width bottom bracket or the use of a 5 speed or 6 speed freewheel. Personally I would use a 3 speed hub gear, but this will not fit into your frame without the frame being set for it. Best of luck with your conversion.