Converting a standa...
 

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[Closed] Converting a standard F/W threaded hub to accept a fixed cog & lockring?

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Right I've got a Fixed/free hub on my bike I've just taken of the Freewheel to discover that it's not got a LH lockring hidden underneath, so I can only safety fot fixed cogs on one side.

I'm very keen on setting the rear wheel up fixed/fixed so I can have a lower commuting ratio and a higher track gear and I only need to flip the wheel not faff with swapping sprockets or stripping lockring threads.

I'm really not keen on either side being a "suicide gear" I've had a look about on the interweb and although people seem to have discussed the idea a bit I don't think anyone has ever really bothered to try and convert a fixed/free hub to a fixed/fixed? especially using a method that allows you not to have to disassemble the hub from the wheel?

I can think of a way of doing it, but it would require a bit of tooling design, and I'd need to source a LH 1.29" x 24tpi die...

Anyone?


 
Posted : 15/04/2013 1:27 pm
 kilo
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I seem to recal you could use a lockring from a bb cup on a rear hub. Tbh i dont think a lock ring is essential for road fixed riding.


 
Posted : 15/04/2013 1:54 pm
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They don't call it a "Suicide gear" for nothing, RH threaded cog with RH Lock ring (taken from a BB) is liable to unwind itself, more than likely at the point you are trying to slow down...

I'd have thought it's also pretty poor form to use such a setup on a track where you are potentially compromising others safety, and some fella's are really shifting, I'd prefer not to be the one to cause an accident by installing a self destructing drivetrain...


 
Posted : 15/04/2013 2:06 pm
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Wil only unwind if you dont snug it up correct. Think the premice of locking nuts together in leui of lock nuts

Tbh if your runnin without brakes then the cog backing off is the least of your worries

For the cost of conversion you would be as well to pick up a cheap novatec fixed fixed hub.


 
Posted : 15/04/2013 2:28 pm
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I have never had a suicide fixed set up come undone


 
Posted : 15/04/2013 2:59 pm
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Edric 64 - Member
I have never had a suicide fixed set up come undone

Great! Hang on... there isn't any qualifying information missing from that statement, like [I]"Because i'd never be so stupid as to use one..."[/I] or [I]Because my bike has a freewheel fitted on that side like you are supposed to...[/I]

But if you lot reckon my concerns over a Suicide setup are unfounded then I might just try it out. Now would it be Wiser to chance it for my "Road" or my "track" gear?

Road = 4 - 5 hours use a week at lower speeds 14-20mph
Track = 1.5 - 2 hours a week but at higher speed (hopefully and trying to hold other riders wheels safely...

Although my intention was always to run Fixed with a front brake only using a top lever, and use my legs for a bit of "engine braking" at the back, is that a shade too much suicide? should I really be using a rear brake? I could buy a pair of top levers and run both, but I'm far keener on having the bike as simple as possible.

Trail Rat you are right probably, a new fixed/fixed hub would obviously cheaper but my brain just looks at what would be involved in making the mod to a hub and it's actually pretty simple on a par withthe sort of faff/complexity involved in facing or chasing Disc mounts/BBs/Head tubes,


 
Posted : 15/04/2013 3:53 pm
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Having it undo is more theoretical than real.
Dog the sprocket up real tight. Use an old steel BB nut as a lock nut, also damn tight. It will stay. You can add a chemical reinforcement if you like. Use no grease and maybe add some salty water. The chemical reaction will bloody well weld the sprocket to an alloy hub.


 
Posted : 15/04/2013 5:47 pm
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Second set of track wheels would be my suggestion, you can usually find a cheap pair with tubs. I seem to recall that some tracks prefer single sided hubs anyway (with lockring). I presume you'll be removing the brake(s) regularly too?

For fixed on the road, I prefer front and rear brakes. And yes, a BB lockring will work just fine. never heard of one coming undone on the road.

My fixed set up is: Miche low flange track hubs with Open Pros for the road and campag/airlite with GP4 and tubs for the track. Both single sided. But I like to ride the track wheels on the road once Spring is here 😀 .


 
Posted : 15/04/2013 6:30 pm
 Haze
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Weld it!


 
Posted : 15/04/2013 6:32 pm
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 kilo
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I would use the "suicide" option on the road where you'll have the benefit of a front brake to do most of the work. As an aside I remember reading years ago that for riding fixed with brakes it was recommended not to have a lock ring that way if the chain shipped or jammed the sprocket just unscrewed and you effectively freewheeled rather than locking the rear wheel up - and I can vouch that it does work!

With regard to two sprockets on the rear; at herne hill I've never had a problem with it but at a private session at newport the coach did say that normaly it would be a no-no there


 
Posted : 15/04/2013 7:01 pm
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You wont be allowed suicide fixed on the track the coach will kick you off if he finds out.Anyone who crashes because you have a problem wont be happy either.I only use mine on the road and with a quick release skewer


 
Posted : 15/04/2013 7:06 pm
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Manchester has very picky rules about the bikes - a second cog isn't allowed


 
Posted : 15/04/2013 7:26 pm
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I'll not be riding Manchester any time soon I only plan to use it at my local council outdoor track on the open training nights I went along last week and it's pretty much a free for all everything from a full on track bike to an MTB with slicks and a nice bunch of people.

I think long term I'll be wanting a second wheel, but for now I will probably suicide my road cog and take things easy.

Cheers for the input all


 
Posted : 15/04/2013 8:55 pm
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What about a [url= http://www.charliethebikemonger.com/surly-dingle-fixed-cogs-152-p.asp ]Dingle?[/url]


 
Posted : 15/04/2013 9:10 pm
 kilo
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as an alternative i bought one of these for a hack training wheel;

http://www.ebay.co.uk/itm/REAR-FIXED-WHEEL-700C-ROAD-BIKE-FIXIE-WHEEL-BLACK-/330881161190?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item4d0a0dd7e6

thirty quid with a sprocket


 
Posted : 15/04/2013 9:15 pm
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I like the Dingle idea but I'm after a bigger difference in sprocket sizes than that offers and 1/8" rather than 3/32" and at £40 a second wheel is a bit cheaper and probably less faff...

I'd already looked at those "Tru-build" wheels last night, and I think that's probably what I'll get, I've already got one of their mach 1 on Tiagra wheels for my geared road bike, and it's actually a bloody good wheel for peanuts, the rims are robust and the spokes were all nice and tight from day one.

I might see how much they want for a QR front hub on the same rim too as it would at least make fixing a front flat on my commute a wee bit less bothersome...


 
Posted : 16/04/2013 8:06 am