Can I convert an MTB to a fixie for the road?

[alchemy]

I might be able to get my hands on an old hardtail MTB frame with vertical drop-outs, canti brakes and 26" tyres. Can I convert it into a fixie that I can use on the road? It's about 15-20 years old with (IIRC) 7 speed Shimano gears, so I think that makes the rear spacing 130mm. A normal road brake for the front would be good.

The other part of the equation is can any conversion be done reasonably cheaply? I suspect that most of the parts are still original so will probably need replacing (the headset and BB certainly will). Thanks

[woollypigs]

Most MTB's I see are single speeds with a chain tensioner, but if you can find the "magic gear" I'm sure that you can, though as the chain wears you can't tension it. I have been thinking the same so I will be following this closely

[harrumph]

Can I convert it into a fixie that I can use on the road? ...reasonably cheaply?

Depends on your idea of "reasonably cheaply". Unless it has horizontal dropouts, I wouldn't think it worthwhile when an off-the peg fixie can be got for about £360. I'd just singlespeed it instead, which costs very little - or nothing, if you've got an old rear mech, a few old cassette spacers and a set of single chainring bolts in your spares box.

[rogerzilla]

Magic gear or ENO eccentric hub. 

The latter is not foolproof and suffers from some degree of axle creep (or, more accurately in this case, axle twist).  I'm trying to find a solution involving longer bolts and serrated washers.

[harrumph]

...ENO eccentric hub...

Except that "reasonably cheaply" has then gone out of the window...

[alchemy]

Thanks for the replies. Sounds like it's a non-starter in the "reasonably cheap" stakes. What would I need to do to make it a single speed? Can I get wheels to fit that will take suitable tyres for the road.

Is there a website that shows you what you need and how to do the conversion?

[Charlotte]

What would I need to do to make it a single speed?

Take a hot glue gun to the gear changers?

[harrumph]

What would I need to do to make it a single speed?

Count your chainring/sprocket teeth and pick a combo that gives you a reasonable gear (say 38x15 or 36x14 on slicks, about 62-3", for the road).

Remove rings and cassette. Refit your one chosen ring with single bolts in middle position.

Using spare cassette spacers, install your one chosen sprocket on the freehub so that it lines up with the chainring and the chain runs parallel to the frame centreline (not critical on a singlespeed - ~2mm out is no big deal).

Install old derailleur (pref. short-arm), without lever or cable. Screw down left-right travel limiting screws so that it sits under sprocket*. Shorten chain so that there is significant tension in the return spring.

Take off all the gubbins you no longer need (gear levers, cables, front mech) and go for test ride  



*if this doesn't work because there isn't enough adjustment... get an old road bike brake cable/install with nipple in derailleur cable tension adjuster and cable clamped at usual place/use cable tension adjuster to move derailleur left-right until lined up/ trim excess cable

[alexb]

Mario Vaz will put horizontal dropouts on for about £30 last time I heard.
New rear hub from On-One is about £30.
Re-use everything else, add a sprocket and lockring (about £20 total) and a chain (from £5)

New headset and BB, plus some single chainring bolts  (£5 from HubJub) could be pretty cheap Shimano UN72 (£15?), for example and then a basic headset is about £15.

That's about as cheap as it's going to get.
If it's a secondhand bike add tryes, brake blocks, whatever else you are going to change.
If these things aren't in the spares box, then you are starting to look at quite a bit of cash for what will end up being an old bike with a lot of money spent on it.

Does the quality of the frame justify that?

[Charlotte]

It might do, but I reckon the postage to Hither Green's going to be a bitch!

[hazeii]

Conversion to fixed will be a bit of a challenge; conversion to single speed will be much easier.

For SS, if you have an MTB rear wheel in reasonable nick just get a suitable rear splined cog and a spacer kit (On-One, DMR, Charliethebikemonger etc) and a tensioner (or look up the bodges to use your old derailleur as a tensioner).

For fixed with vertical dropouts, the issue is tensioning the chain. You *cannot* do this with a chain tensioner (because bad things will happen) so you're into a new rear wheel (or serious bodging of the old one) plus all sort of other arcania involved half-links, magic gears, strong QR's, filed dropouts and frequent fettling.

If you're determined to go fixed, much better to look around for an older frame with horizontal dropouts instead.

[woollypigs]

It might do, but I reckon the postage to Hither Green's going to be a bitch!

HA! yeah you can't trust royal pain to get it there either

[JonBuoy]

For fixie chain tensioning what about using a ghost ring as seen here ?

[border-rider]

For fixie chain tensioning what about using a ghost ring as seen here ?

I'd really not fancy that at 200rpm

More on this (fixing with v dropouts) on the FixieFAQs - magic gears are actually quite do-able.  My Zeppelin (as featured on last year's Swindon Ride)  is magic'd and works a treat

[andygates]

The ghost ring scares me.  I'd definitely give it a go with a magic gear.

[hazeii]

....
More on this (fixing with v dropouts) on the FixieFAQs - magic gears are actually quite do-able.  My Zeppelin (as featured on last year's Swindon Ride)  is magic'd and works a treat

While I'd agree magic gears are do-able, I find they require a degree of expertise and a stock of spare bits to arrive at a working solution.

And then, as soon as the chain tension needs twiddling (for me, within a couple of hundred miles even with run-in parts used in the first place) the whole process needs to be repeated.

[woollypigs]

I can just see the ghost ring fall off and take off some spokes when it gets jammed into the back wheel. Though that looks well cool

[Martin109]

An example of a magic gear solution is shown here.