Feasible SS/Fixed project?

dhope

Sister and I know nowt about bikes but like them none the less. She's about 5'1" and has a junior Raleigh that looks a lot like this



It has 600a wheels. Anyone with any experience of catering for midgets know how feasible it would be to turn it into a SS, what I should be looking for or any gotchas etc.

Ta

SamWise72

I can't see the picture, but two things to be aware of; you'll need to have wheels built if you want to go fixed. Chances are you can remove the freewheel and put on an SS freewheel, but for fixed you need a hub with a lockring thread, and this won't have it, plus no chance of finding appropriate wheels prebuilt in that siz. Scond, you'll hav vry limitd choic of tyrs (sorry, my "e" key is being intermittent!)

wgwarburton

SamWise72 wrote:

... but for fixed you need a hub with a lockring thread, ...

It's not absolutely essential. If you're planning on running a rear brake and not doing much skid stopping then many have found that you can manage fine without a lockring.

It's your call, your risk but I've personally been riding fixed for several years now and I've yet to use a hub that has provision for a lockring. The only times I've experienced any unscrewing are when I'd just fitted a sprocket and not bedded it in. It feels a bit wierd, but as soon as you realise what's going on you can just start pedalling and screw it back up again! Obviously you can't delay too long or the sprocket will pop off the thread... :-)

Cheers,
W.

EKE_38BPM

dhope wrote:

Anyone with any experience of catering for midgets...

Ask CafeWanda


I'm sorry, I could only resist so long.

She really is going to kick me in the shins. I promise to buy her a drink to make up for my constant ribbing.

nicklouse

for SS if it has a cassette and not a freewheel (spin on block) then any SS kit can fit (be made to).

PS picture link fixed.

wgwarburton

nicklouse wrote:

for SS if it has a cassette and not a freewheel (spin on block) then any SS kit can fit (be made to).

PS picture link fixed.

I can see the bike, now, thanks Nick.

That looks to me like it should be a straightforward conversion. Going by the visible parts on the bike it looks like it has a freewheel, rather than a cassette (how many sprockets at the back? I'd guess six or maybe five).

Assuming you're happy to run a rear hub without a lockring:

You need to take the freewheel off and put on a fixed sprocket (it's a straight swap, they have the same thread). If you're going SS, not fixed, the lockring isn't an issue anyway.
You might get away with reusing the chain, if it's not worn.
The chainset is steel. Unless you're building a winter hack I'd change it.

Your LBS should be able to help with the wheel (though they'd probably prefer to sell you a new one), so replace the chainset and get a suitable sized single (anything from about 42 to 48 teeth can be made to work easily, bigger or smaller with a bit more thought), then get a rear sprocket to suit the gear you want (high 60s/low 70s is a good starting point) and get them to swap the cogs & re-dish it to suit.

Gear charts and calculators abound- make sure you pick one that lets you select the smaller wheel size you are using.

Cheers,
W.

lainey_85

Hello, said sister here : )

Here's a link to a picture of the bike in question:
http://img221.imageshack.us/img221/9153 ... eugeot.png

Please excuse any stupidity - I really do know very little about bikes… the additional problem I've got is that the front wheel needs replacing, it has a massive dent in it, but finding 600a wheels is a nightmare, so I was wondering if we can replace the wheels with a more standard size wheel, get rid of the brakes and convert to a fixed gear? Is it possible to change the size of wheel from a 600a to a more standard size or am I talking jibberish?

Ta

dhope

lainey_85 wrote:

Hello, said sister here : )

Here's a link to a picture of the bike in question:
http://img221.imageshack.us/img221/9153 ... eugeot.png

Please excuse any stupidity - I really do know very little about bikes… the additional problem I've got is that the front wheel needs replacing, it has a massive dent in it, but finding 600a wheels is a nightmare, so I was wondering if we can replace the wheels with a more standard size wheel, get rid of the brakes and convert to a fixed gear? Is it possible to change the size of wheel from a 600a to a more standard size or am I talking jibberish?

Ta

Ello sis,
Hm, I didn't realise you were thinking of a brakeless fixie. Front brake at very least would be preferable methinks, or I'll feel responsible when you career into the back of a lorry.

dhope

So on the 600 A to (possibly) 650 C wheel idea - Sheldon says the diameter difference is only 97mm, which is only 15mm difference in radius. Could surely get some brakes with shorter drops or similar?

rjsterry

600a rims are 24" x 1 3/8", so you could look at some other more readily available 24" rims. Airnimals use 24 " wheels I believe, so they might be suitable.

lainey_85

Guys at my local bike shop reckon I'd have all sorts of problems with the brakes if I changed the size of the wheels… which was why I thought brakeless… for fun - not for commuting, I don't wanna die!
My local bike shop got out what they said was a 24" wheel and it was loads smaller, which doesn't seem to make sense… can anyone shed any light?

dhope

http://www.sjscycles.co.uk/wheel-rear-2 ... l-prod2936

?

dhope

lainey_85 wrote:

Guys at my local bike shop reckon I'd have all sorts of problems with the brakes if I changed the size of the wheels… which was why I thought brakeless… for fun - not for commuting, I don't wanna die!
My local bike shop got out what they said was a 24" wheel and it was loads smaller, which doesn't seem to make sense… can anyone shed any light?

Measure the diameter
http://www.sheldonbrown.com/rim-sizing.html

nicklouse

sorry but is it really a 600A wheel?

rjsterry

I was wondering the same. 600A is a small road wheel size, albeit rare/obsolete. But 600A is definitely 24" diameter.

BTW, that 24 x 1 3/8" wheel that SJS have looks like it's been in the warehouse a while.

nicklouse

rjsterry wrote:

I was wondering the same. 600A is a small road wheel size, albeit rare/obsolete. But 600A is definitely 24" diameter.

BTW, that 24 x 1 3/8" wheel that SJS have looks like it's been in the warehouse a while.

well not quite. that is the Wheel diameter with tyre. rim bead is 540mm and even when adding the braking surface, say 12mm total you are still short of 24" measured diameter.

540mm = 21 inch

even an MTB 26" wheel is "only" 22" on the bead.

lainey_85

I'll measure it as soon as I'm home…

nicklouse

also check the info on the tyre sidewall.

rjsterry

nicklouse wrote:

rjsterry wrote:

I was wondering the same. 600A is a small road wheel size, albeit rare/obsolete. But 600A is definitely 24" diameter.

BTW, that 24 x 1 3/8" wheel that SJS have looks like it's been in the warehouse a while.

well not quite. that is the Wheel diameter with tyre. rim bead is 540mm and even when adding the braking surface, say 12mm total you are still short of 24" measured diameter.

540mm = 21 inch

even an MTB 26" wheel is "only" 22" on the bead.

True, it's not a 24 " diameter rim, which is what most people would measure. I was meaning that a 600A wheel might also be sold as 24 x 1 3/8", which might be easier to find.

nicklouse

yep but knowing what goes on in bike shops I thought it would be best to clear it up.

brings back memories of a guy popping in for a 22" tyre for his 22" wheel. finally found some old stock... he says that looks small.

he had a 26" wheel.

Alphabet

for the gears conversion, get yourself to velosolo.com. they're lovely and produce some good stuff for replacing your cassette with a single cog and spacers. also makes lining up the chainline easy.

SamWise1972

You could buy a spacer kit, or just a length of water pipe in the appropriate diameter

lainey_85

Definitely is a 600a, measured it at the weekend - just over 21", with tyre just over 24"… does anyone know of a more standard wheel that might fit or shall I stay on the hunt for a pair of 600a's?

Ta,
Lainey

rjsterry

Looking at Sheldon, the nearest similar size would be 24" x 1 1/8". This is 20mm smaller in diameter, so you would need brake calipers with 10mm more drop to reach them (Tektro make some 'long drop' calipers). The rim would also be narrower by 1/4", but I don't think that would be too much of an issue.

As I mentioned before, Airnimals use 24" or ISO 520 rims, built onto standard Shimano road hubs. This shows some information on manufacturers of suitable rims.

ETA: Just to warn you, reducing the wheel size may make the handling go a little odd.

dhope

rjsterry wrote:

Looking at Sheldon, the nearest similar size would be 24" x 1 1/8". This is 20mm smaller in diameter, so you would need brake calipers with 10mm more drop to reach them (Tektro make some 'long drop' calipers). The rim would also be narrower by 1/4", but I don't think that would be too much of an issue.

As I mentioned before, Airnimals use 24" or ISO 520 rims, built onto standard Shimano road hubs. This shows some information on manufacturers of suitable rims.

ETA: Just to warn you, reducing the wheel size may make the handling go a little odd.

I was thinking 650c. 31mm larger diameter, so would need around 2cm frame clearance to accommodate the 15.5mm radius...
And 650c would be more standard in terms of road bike rims etc, some TT bikes having them etc?

lainey_85

There is about an inch more space but assume that'd make it pretty tight and mean no brakes?!