question on single/fixed gear bikes

kumate_champ07

can you adjust the single gear? I want something I can ride at high enough speed, I dont mind having a slow take off and have fairly strong legs

Morgan

Yes, you can install whatever chainring and cog combination you like (within reason).

kumate_champ07

thats if I build one myself? how can I tell how 'hard' the gear is gonna be?

heres the bike I'm interested in:


http://www.cyclesuperstore.ie/shop/pc/viewPrd.asp?idcategory=35&idproduct=30738

Dr.Millah

This will tell you how hard the gear will be. Input the number of teeth in the chainring and the rear cog http://software.bareknucklebrigade.com/rabbit.applet.html . I cycle on a 72" ratio in cork city and find it good for speed and getting up hills. Its not too hard to lower or higher the ratios after but it will cost the price of a new rear cog with less or more teeth.

The above bike has a 74" ratio.

Morgan

Work out the "gear inches" for that particular gear combination. Essentially this is the distance covered per pedal-rotation. You can use a pencil and paper but there are plenty of tools online that will work it out for you. Here's one:

http://software.bareknucklebrigade.com/rabbit.applet.html

You could compare that to a gear combination you're already using (a higher number is harder to pedal).

flickerx

kumate_champ07 wrote: »

can you adjust the single gear? I want something I can ride at high enough speed, I dont mind having a slow take off and have fairly strong legs

Then put on a bigger chainring at the front, say a 46, 48, or 49t, and a smaller sprocket at the back, a 13, 14, or 15t.

I have 13t and 15t sprockets for sale if you want one

kumate_champ07

Im still confused by all of this! I'll just have to try the bike out before I buy it and then get different parts later if needed.

also was wondering why you cant see any brakes on that bike? in the spec it says 'Brakes - Alloy Dual Pivot'

blorg

I'd stick with the typical ratio you get and see how you get on. The Bowery comes 46-17 (73") and this is a good general ratio for getting around a city and up a few hills. Part of the joy of a fixed gear is that it forces you to work on your cadence and pedalling technique. No point just going immediately to a ridiculous gear and mashing it really slowly.

Cogs are generally cheaper than chainrings and you are less likely to need to buy a new chain. Bear in mind there are two fixed standards for sprocket/chain/chainring width, 1/8" and 3/32". That Bowery is 1/8".

Giant leave the brakes off in the stock photos as they think it looks better. The bikes come with brakes attached.

flickerx

kumate_champ07 wrote: »

Im still confused by all of this! I'll just have to try the bike out before I buy it and then get different parts later if needed.

Its not that difficult.

See the chainring? The ring nearer the front of the bike?
The smaller that is, the easier it is to cycle.
The bigger that is, the harder it is to cycle.

See the sprocket? The ring nearer the rear of the bike, on the wheel?
The bigger that is, the easier it is to cycle.
The smaller that is, the harder it is to cycle.

IM0

but you can get a flip/flop hub with 2 gears on the rear wheel and you just flip it around (the wheel) to use the harder or easier gear.

blorg

flickerx wrote: »

Its not that difficult.

See the chainring? The ring nearer the front of the bike?
The smaller that is, the easier it is to cycle.
The bigger that is, the harder it is to cycle.

See the sprocket? The ring nearer the rear of the bike, on the wheel?
The bigger that is, the easier it is to cycle.
The smaller that is, the harder it is to cycle.

It's exactly the same as a geared bike, just changing the gears is a more involved job.

petethedrummer

Hard Gearing


Easy Gearing

blorg

Hard gearing (I think he actually had a bigger chainring but this one worked better)

kumate_champ07

petethedrummer wrote: »

Hard Gearing


This I would like but Im worried about my weight on it, I'm 110kg 6ft 3.
I think I need a 62cm frame, looking back at the link I posted that bike is prob not available in my size. If I was buying new I have a place to go where I would get a good deal but I wouldnt mind buying an old racer and taking off the gears myself. would I need upgraded wheels for my weight?


does anyone here know anything about Rothar in Phibsboro, Dublin? they let you rent their space and tools, think they give you a little guidance too

Is 200euro a good price for an old racing bike? how much would the fixed gear parts cost?

abcdggs

Flickerx above volunteers there on a regular basis, he'll be able to fill you in. From what i've heard it's a great place and everyone seems very helpful

flickerx

Yeah Rothar let you use their tools for a fiver an hour. They pretty much have everything tool-wise down there you would need for doing a conversion from an old road bike to a fixie. City Cycles in Blackhall Place is your best best for buying a fixed rear wheel, they have flip-flop Raleigh Mach1 wheels that come with a 16t fixed sprocket and a lockring for €70. I'm down in Rothar a fair bit, but not every day. You could do worse than join up at http://www.dublinfgss.com and ask around for a 60cm frame, people are always trading stuff on there. People will also give you advice and help on that board (and here too).

I might be running a workshop in Rothar some time soon (http://www.dublinfgss.com/viewtopic.php?f=2&t=218) explaining exactly what you're looking for, and PhatYack might do some instruction on stripping and repainting a frame.

flickerx

petethedrummer wrote: »

Hard Gearing

Is that a Graeme Obree bike? I think I recognise it from a book I read with a piece on him in it.

blorg

flickerx wrote: »

Is that a Graeme Obree bike? I think I recognise it from a book I read with a piece on him in it.

Yes, he was planning last year to go for the hour record on it but then decided against it.

http://www.bikeradar.com/news/article/graeme-obree-bidding-for-hour-record-again-21712
http://www.bikeradar.com/news/article/graeme-obree-dumps-hour-record-plans-23985

Harrybelafonte

Personally, I'd suggest you try the Bowery and see what you think before making any other plans. If you already have a multispeed bike keep it in the one combination you find you can keep in for all different uses, i.e. uphill, downhill, flat. I have a Bowery and use it in city centre and on road up through Drumcondra and Whitehall. My gearing means I'm out of pedal on downhills but its at a healthy speed, probably well over the 40km mark which is ebough for me and I can still pedal up that same hill at a healthy pace. I'll probably change in the summer but for the moment everything is doable. Try it out in the shop first, The least it will do is give you an idea of what cogs to put on the one you might build.

niceonetom

Might be worth pointing out that the white bowery above is intended for tricks, or at least intended to look like it's for tricks - I doubt you could spin those bars though.

The down sides of this, aside from being judged harshly by people like me, are the it seems to come with a BMX style front crank and chainring which mean a limited choice of rings, all small, and a stem that will lead to very twitchy handling at any decent speed. A normal bowery would be a much more versatile and tunable bike, and would attract fewer condescending glances from the fixie elite.

LastGasp

niceonetom wrote: »

it seems to come with a BMX style front crank and chainring which mean a limited choice of rings, all small, and a stem that will lead to very twitchy handling at any decent speed.

Acc to the link it comes with a 48 Chainring, and according to the Blorg its 46. Either way it's not THAT small. I ride 44/17 for my commute, which I find fine. 46(or 48) /17 would be a pretty good starting point for the OP. Admittedly I'm a wimp, and not a registered member of the Fixie Elite !

niceonetom

Yep, you're right LG. 48x17 is the gear I run most of the time as it happens. I'd still advise the OP to go with a version that has a standard spider-and-ring setup. BMX bits on a road/track bike is just wrong and that stem is insane.

kumate_champ07

I'd just like to add, my last bike which was stolen monday this week, it was a 24speed dual suspension dual disc brake MTB which I rode around the city on short&long journeys. I used 1 gear most of the time, I like the challenge and its a great workout for my legs.

I was able to ride rough with that bike(up/down curbs,over potholes etc) but I dont think I could with a typical fixed gear bike. So I will prob have to change my riding style. Ive read a little about 'fixies' and I dont really care about fitting in with a sub culture, Im just interested in riding the bike every day and I'd like it to look nice too. that bmx style fixie looks nice to me, but Im not great on technical terms in relation to bikes, I need a strong bike but I will go easy on it if needed.

found another 1 here I like
http://www.eurocycles.ie/Hybrid_Bike_Gents/Felt_Brougham_-_2010/3610_p.aspx

blorg

kumate_champ07 wrote: »

I used 1 gear most of the time, I like the challenge and its a great workout for my legs.

Gearing has very little to do with the workout you will get, spinning a lower gear fast will give you a workout just as well as grinding in a higher gear. Probably a better one in fact and certainly less likely to give you knee injuries.

kumate_champ07

blorg wrote: »

Gearing has very little to do with the workout you will get, spinning a lower gear fast will give you a workout just as well as grinding in a higher gear. Probably a better one in fact and certainly less likely to give you knee injuries.

I mean anaerobic workout.

blorg

kumate_champ07 wrote: »

I mean anaerobic workout.

You can most certainly go anerobic with an easy gear and high cadence, what are you trying to achieve here? The whole "big gear" thing is macho nonsense that only serves to build bad technique, make you go slower and pick up injuries. Unless you are going to be riding it around a track stick to an easier gearing, especially starting out, and if you want a workout go cycle up (and down) some mountains. You'll get the power mashing on the way up and a master class on your cadence on the way back down, best of both worlds.

kumate_champ07

blorg wrote: »

You can most certainly go anerobic with an easy gear and high cadence, what are you trying to achieve here? The whole "big gear" thing is macho nonsense that only serves to build bad technique, make you go slower and pick up injuries. Unless you are going to be riding it around a track stick to an easier gearing, especially starting out, and if you want a workout go cycle up (and down) some mountains. You'll get the power mashing on the way up and a master class on your cadence on the way back down, best of both worlds.

well I guess we both have different preferences. I like a big gear for the same reason I like deadlifting or squating alot of weight, I just like the feeling of high resistance. I like the way my body feels from it, its a physical pain that can be enjoyed. my ass also never leaves the saddle once I get on the bike

I dont plan on going up mountains, just bridges and the climb from clanbrasil st. up towards christchurch.

Greyspoke

If you want to go fixed and you're not sure what gear you want, check this out: http://www.pearsoncycles.co.uk/product/4685/PEARSON_150_LIMITED_EDITION_3_SPEED_FIXED
Interesting idea but for me a bit part of the fixed appeal is that you do only have one gear and no choice.

kumate_champ07

an update with more questions!
called over to my grandad at his farm a couple of days ago and decided to have a look in an old stable/shed. to my surprise I found an old rusty 5speed raleigh racer! I think its from the 70's. not sure the frame size but it feels comfortable enough to sit on.

Im converting it to fixed gear but I'm having trouble, yesterday I discovered that the wheels are 27 1/4 inch iso630. Ive got new tyres and tubes, chain, chain breaker,brake pads for the front, brake cable. the chain ring is 52t, is it ok for fixed gear? It seems to wobble very slightly when grabbed

After fitting the front wheel with new tube and tire I noticed it wobbled a bit when I stuck it back on the bike, I dont recall it doing that before.

the frame itself is rusty(on white paint) but I dont mind leaving it like that so it doesnt stand out. I'm thinking of buying this:

http://www.wiggle.co.uk/p/cycle/7/Miche_Primato_Large_Flange_pair_of_Track_Hubs/5360040675/
and having the wheels rebuilt with the original alluminium rims, spokes seem fine.

how much would it cost for someone to rebuild the wheels? and possibly put the bike together?

kumate_champ07

not sure if the rear hub in that set is fixed but heres a fixed rear hub, is this any good?

http://www.wiggle.co.uk/p/cycle/7/Miche_Primato_Large_Flange_Flip-Flop_Rear_Track_Hub/5360042842/

blorg

kumate_champ07 wrote: »

how much would it cost for someone to rebuild the wheels? and possibly put the bike together?

Rebuilding wheels is a bit of a big job, Mr Skeffington probably your cheapest bet.

Bear in mind you only have to rebuild (or replace) the rear wheel, no need to change the hub in the front. If you will be keeping both brakes and don't plan on skid stopping you may be able to thread a track sprocket onto the wheel as it is, not 100% sure on that, would depend on the wheel.

If you are changing I would probably just change the lot for modern 700c wheels as tyres could be more difficult to get in that size.

gman2k

kumate_champ07 wrote: »

http://www.wiggle.co.uk/p/cycle/7/Miche_Primato_Large_Flange_pair_of_Track_Hubs/5360040675/


how much would it cost for someone to rebuild the wheels? and possibly put the bike together?

I'm just after buying this and I got a miche primato rear hub also - as per the wiggle link.

You can budget 30-35 yoyos for building a wheel - you supply hub and rim, builder supplies spokes.
I was thinking of buying a pair of these rims, cos they are cheap, and so am I.