Bicycle Mechanics - Fix gear conversion? can it be done??

I am wondering if this bike can be easily converted to a fix gear bike??
http://i42.photobucket.com/albums/e347/Courtg35man/CPCCycles002.jpg
http://i42.photobucket.com/albums/e347/Courtg35man/CPCCycles007.jpg

Yes

what would need to be done? cheapest way
And is the crank able to take the beating better then a sold crank?

what needs to be done? (think cheap)
can this crank take the beating?

http://sheldonbrown.com/fixed-conversion.html
http://sheldonbrown.com/deakins/how-to-fixed-conversion.html

cheapest probably: use current hubs and crank with existing or road chain, but get cogs designed for road chain as one speed chain won't work with present crank/chainrings very well, too wide. Use a bottom bracket lockring for a lockring on your hub, I bought and assortment of cogs 20t-16t to match the training, terrain and my "shape" I was doing and in. leave on at least one brake (front), preferably both, they'll save your butt!!

+1 on the brakes. Don't even think about riding brakeless on a converted freewheel hub.

The Sheldon Brown links below are your best source of info for sure. Focus on the chainline - it really does have to be right or you'll get noise, worn out parts or much worse.

Piece of cake. Read the Sheldon stuff. The only hiccup will be the crank. To have anything like a useable chainline, you will need to bring the chainrings in as tightly as you can to the chainstays. (Even so, you will have to respace and redish the wheel, and almost certainly be forced to make the wheel be off-center towards the right.)

The crank you have on there now appears to have bolts holding on the inner ring, so that ring can be removed, but then you will be using the larger ring which is considerably farther outboard. I doubt that you have much chance of getting a useable chainline using that large/outboard ring. You could use the inner/smaller ring, but then you will have to leave the larger one on. This might work just fine, but it will be ugly to have that bigger ring out there doing nothing. People in this position sometimes grind the teeth off the larger ring and have it play the role of a bashguard. This would give you two bashguards, so I am not sure that is any cosmetic improvement.

I might sugggest you go to your LBS and see if they have a cheap/beat up/used crankset they will sell you. I would guess that if they do, they will sell it for $5 to $20. Of course, if that new crankset is not cottered (which it most certainly will not be), then you also have to get a non-cottered spindle to go with it. Also not expensive, especially if it is used.

jim

+1. Pretty easy. Be willing to shell out extra when you screw up once or twice, but totally doable. Alternatively, a $40 fixed-specific rear wheel can be had, eliminating the worry of possibly ruining the hub.

MMM. A fixed-specific rear wheel does not solve all the problems for you. They come with the hub spaced symetrically. Which is to say, they are set up for a chainline that is pretty far inboard. With road width chainstays, a road BB spindle, and a road crank, it is usually pretty hard to work with that chainline. So, even track wheels have to be respaced and redished. Yes, there are plenty of advanages to using a real track wheel, but cutting down the steps in the conversion process is not one of them usually.

jim

p.s., it is still not a big deal; I am not trying to talk anyone out of it.

http://sheldonbrown.com/fixed-conversion.html
http://sheldonbrown.com/deakins/how-to-fixed-conversion.html

+1 to these

Jack

I have to disagree, Igedwa. When I built up my fixed wheelset, chainline was easy as pie. Road crank, BB, rear spacing.

I have to disagree, Igedwa. When I built up my fixed wheelset, chainline was easy as pie. Road crank, BB, rear spacing.

+1. I converted a Raleigh Gran Sport with a Stronglight 93 crankset using the original Normandy hub wheels. After a bit of spacer-juggling and re-dishing, the chainline is perfect and the tire is right in the middle of the stays. True, I have the chainring on the inner ring position, but it appears that if I flip the axle the outer position would be about right, and look a whole lot better. Eventually I'll get around to it.

Alternatively, a $40 fixed-specific rear wheel can be had,.

Where?

$40 for a track rear wheel? you're dreaming.

New - you will be hardpressed to find one under $100US I imagine.

I just got a pair of 2nd hand but barely used wheel set for £50 + Postage. the cheapest price I coudl fidn in London new was around £115 = ~ $230 US.

speaking of chainline - I would think that if you go to a Trackwheel with even dish then the rear cog will end up OUT further from the centerline than on a geared Bike wheel which is dished to one side.

so wouldn't it be easier to get a good chainline with a track wheel than an old geared wheel?

If I may ask a stupid question...why do you want to convert the bike?

The crank you have on there now appears to have bolts holding on the inner ring, so that ring can be removed, but then you will be using the larger ring which is considerably farther outboard. I doubt that you have much chance of getting a useable chainline using that large/outboard ring. You could use the inner/smaller ring, but then you will have to leave the larger one on. This might work just fine, but it will be ugly to have that bigger ring out there doing nothing. People in this position sometimes grind the teeth off the larger ring and have it play the role of a bashguard. This would give you two bashguards, so I am not sure that is any cosmetic improvement.


jim

I don't think they are bashguards -- the original one is a for stopping trouser cuffs getting caught in the chain.

The "bolts" on these old steel cranksets sometimes are faux ones and sometimes real. On this one, the original cuff-guard is likely attached with nuts and bolts and the chainrings are riveted.

On my set-up, I removed the cuff guard, then attacked the teeth on the outer chainring with a pair of pliers first, before grinding down what was left with a file. Looks pretty good to me and serves a vital function -- if you've ever had the cuff of pants caught in a fixed-gear chainring, you'll know what I mean. But then it's probably not cool to ride with the right pants cuffs rolled down...

It's the God's honest, I swear. There's a guy in my neighborhood (Boston) who builds cheapie flip-flops for $30. See the link

http://boston.craigslist.org/gbs/bik/479711272.html

While I'm at it, the whole kerfuffle over fixed chainline is just overdone. It's not hard to accomplish, and people seem to scare newbies away from attempting it. I've never had trouble achieving an acceptable chainline.

If you use the inner chainring you will not need to redish at all, you could even use your outer with little problem. I'd be very surprised if you're strong enough to need the outer ring. The spacing on your 5cog/10 spd bike is 120 mm., which, if memory serves is the same as purpose built track wheels. I turned an old Bianchi w/126 mm spacing into a "fixie" and stuck the "road spaced cogs" on a seven spd hub and used the same chain no problem, all I had to buy were the cogs with "road [thickness]teeth) 16,17,18,19 and 20 tooth used with a 39 tooth innner ring. ( I already had a BB lock ring I used as the hub/cog lockring. I saved the extra chain derailleurs etc. I could change it back to multi-speed in less than an hour.

While I'm at it, the whole kerfuffle over fixed chainline is just overdone. It's not hard to accomplish, and people seem to scare newbies away from attempting it. I've never had trouble achieving an acceptable chainline.

Agreed. It's fixie-babble to make themselves feel important and set apart from the rest of the cycling world. :D

Agreed. It's fixie-babble to make themselves feel important and set apart from the rest of the cycling world. :D

No one is trying to scare anyone off. The factors in getting a good chainline are many, but none of them is really hard to manipulate.

I have to disagree about the importance of chainline on a fixed gear. A moderately bad chainline will cause noise and wear. A bad chainline will perhaps cause the chain to jump off the cog. No one who has had this happen on a fixed gear would call this fixy-babble.

Get the chainline right. It is not hard, and with luck is not expensive.

jim

No one is trying to scare anyone off. The factors in getting a good chainline are many, but none of them is really hard to manipulate.

I have to disagree about the importance of chainline on a fixed gear. A moderately bad chainline will cause noise and wear. A bad chainline will perhaps cause the chain to jump off the cog. No one who has had this happen on a fixed gear would call this fixy-babble.

Get the chainline right. It is not hard, and with luck is not expensive.

jim


Lighten up, and stop taking yourself so seriously!!! I haven't had a chain come off with (a) slack chain (b) no totally accurate, straight chainline and (c) shock and horror, with a Biopace chainring.

I am a firm believer in people TRYING THINGS FOR THEMSELVES and finding out rather relying on what others might promulgate.

I'll try this again... :D

Lighten up, and stop taking yourself so seriously!!! I haven't had a chain come off with (a) slack chain (b) no totally accurate, straight chainline and (c) shock and horror, with a Biopace chainring.

I am a firm believer in people TRYING THINGS FOR THEMSELVES and finding out rather relying on what others might promulgate.

I'll try this again... :D

I think my serious ape avatar leads people to believe I am more serious than I am. My apologies for that.

I agree that people should play around with these things and get a feel for it. The whole appeal of bike mechanics, for me, is that the entire system is simple enough that one can just think themselves through most any problem. It is just plain fun to bumble toward a solution.

On the other hand, one wants to avoid some bumbling.

Sure, there are slack chains that have never jumped. I have run some of them. There are bad chainlines that have never jumped. I have run some of them. But they do open up a possibility that is rather dangerous, and so they are to be avoided. Since it is not so hard to avoid them, I highly recommend they be avoided.

Setting aside any serious issues, there is also the issue that a smooth drivetrain that spins like butter is just a beautiful thing. Nothing makes my tinkerer's heart sing like a silent bike.

jim

How cheap?

No one is trying to scare anyone off. The factors in getting a good chainline are many, but none of them is really hard to manipulate.

I have to disagree about the importance of chainline on a fixed gear. A moderately bad chainline will cause noise and wear. A bad chainline will perhaps cause the chain to jump off the cog. No one who has had this happen on a fixed gear would call this fixy-babble.

Get the chainline right. It is not hard, and with luck is not expensive.

jim

I doubt many fixed riders even know what their chainline measurement is.