Looking to buy a nice hard tail mountain bike and do a SS conversion myself. This niner mcr has caught my attention but doesn't have a sliding drop out. I saw a calculator somewhere someone had for exact chainstay lengths and teeth counts to calculate a tight chain length. Anyone know where something like that is ?
Also if there is anything to look out for or better options when buying conversion kits.
Cheers !
by jimmirekard
7 Comments
Niners have eccentric bbs which helps with the conversion. Check to see if that one does. I am looking into the Niner SIR9 2012-2014 model as a potential gravel build.
Honestly, don’t try the magic ratio method. It might work but it’s a pain to set up (sometimes you need to mess with half links etc), it limits your gear ratio and as the drive train wears you loose chain tension. Go with a chain tensioner that mounts where the rear derailurer goes like from Paul or an eccentric bottom bracket
If the bike has an iscg mount at the bb (for chainring protection and chain guides) you can a chain guide from mrp or funn or any other brand that has one pulley wheel to tension the chain.
Looks better imo and is also pretty versatile.
Something like this:
https://www.bikefit.co.nz/products/funn-zippa-lite-chain-guide-1
Don’t! If you’re buying a bike, buy one that’s intentionally a single speed. Conversions seem like a good idea until you really get into one. There’s limited cases where it makes sense, but if you’re posting the question on Reddit I’m betting you don’t have the mechanic experience to have a good time with this.
Hardtails are the easiest to convert. Tons of options for chain tensioner from cheap to premium, if u look at the right places. Forget magic gear and all that nonsense, its more of a luck than mechanics. Your current rd is essentially a chain tensioner after some simple adjustments. I suggest u start with that. It costs u zero and works really well.
You need the following:
1. A chain tensioner
2. A single speed cassette conversion kit with a cog and spacers
3. A narrow wide chainring
4. If you buy a bike with a 3x with riveted chainrings, you will need to buy a crankset and some single speed chainring bolts.
I bought all these things on AliExpress very cheap. Chain tensioner was around $15, single speed conversion kit is around $15, narrow wide chainring is about $5, cranks can be found for $20 – $30, and chainring bolts are around $2.
Thanks everyone, appreciate the input. I already ride a SS (Sunday high c bmx) and know I will love one, given me the ammunition to just spend the money on a nice dedicated bike.