The Fixie Thread

[mitchy_]

i was going to try 38/16 as i had a 38T ring and stock fixed gear is 16... but if i go the stock 48T crank and buy a 20T freewheel i'll be about the same as you say.

i thought these single speeds were supposed to be easy... confusing the poop out of me for the whole 4 parts that make up the bike!

 

[Danny B]

Unfortunately bearings die under hard use, and the interface is a little flexy.

In my experience quality sealed cartridge ST bbs - Sugino, TA, Campy, Tange - ALWAYS outlast Outboard BBs. Sealing on them is far superior. As for flex I scoff at that. If its good enough for Hoy, Bauge, Perko et al its will hardly be a problem for you with your 42/16. Also lots of WC singlespeeders still run WI and Middleburn cranks. Your argument is invalid.

A Sugino messenger crankset is a RD2 crankset (read Road Double) fitted with a single chainring and a 108mm BB for a narrower chainline. You could just as easily use another ST/Octo/Isis 130bcd road double crankset and run the BB spindle length correct for your chainline. 130 unramped chainrings are easily available in one tooth increments.

If you're riding street fixed I'd recommend running 68-73 GI, lower end if brakeless, higher with a front brake. If your running SS maybe 60-65GI

As for wheels look at Miche Primato Pistards if you're on a budget. Good wheels and cheap as chips from ribble etc. Also look at Velomine for cheap wheels with reasonable and fast shipping from the states.

Track wheels are often heavier than road wheels because track riders generally prioritise stiffness over weight in a (training) wheel. If your bike weighs in at 8-9kgs you'll probably be faster than the dude riding his 6.7kg bike with 16 spokes and noodles for rims.

 

[Danny B]

Mitchy Ok so fixed. If you need to change your track cog you'll need to use a decent chainwhip and lockring tool (like the Shimano Dura-ace one) It has to be done up FKN tight. And make sure you keep the teeth away from your knuckles or forearm.

If in doubt take it to a shop that works on Fixthies and get them to do it. You can trash a track hub pretty quick braking on a marginally loose lockring, you can also cut yourself quite badly installing lockrings and cleaning chains. (My buddies brother clipped the end of one finger off doing this). Not being a drama queen just stating facts.

 

[Danny B]

Sorry to say it but anything over 18T at the back or smaller than 46T on the front ≠ badass.

This on the other hand...

 

[mitchy_]

wheels are sorted, keeping the stock ones. i thought the freewheel was part of the hub, like a regular freehub body for a cassette. bought an 18T free wheel today chucked behind the 48T. will probably go a bit smaller on the crank to begin with though, there are a few decent hills around where i live... no idea on what that is in gear inches, but i'm not out to be badass. it's purely for fun as i have a near identical bike with less weight with 10 gears...

i figured the wheels (and bike) was built for strength and power transmission.. the spokes make my other wheels look like cheap spaghetti. i was just concerned about new wheels being ~2500 grams for the pair when i'm used to ~15-1700 grams.

 

[Danny B]

wheels are sorted, keeping the stock ones. i thought the freewheel was part of the hub, like a regular freehub body for a cassette. bought an 18T free wheel today chucked behind the 48T. will probably go a bit smaller on the crank to begin with though, there are a few decent hills around where i live... no idea on what that is in gear inches, but i'm not out to be badass. it's purely for fun as i have a near identical bike with less weight with 10 gears...

i figured the wheels (and bike) was built for strength and power transmission.. the spokes make my other wheels look like cheap spaghetti. i was just concerned about new wheels being ~2500 grams for the pair when i'm used to ~15-1700 grams.

48/18 is a great ratio. low 70s. Perfect. You'll be fine unless the hills are really big. I used to train on low hilly terrain with that ratio. On the flat I rode 48/15 (mid 80s). You'll be fine. Enjoy it and have a go riding fixed its a good buzz.

 

[g-fish]

In my experience quality sealed cartridge ST bbs - Sugino, TA, Campy, Tange - ALWAYS outlast Outboard BBs. Sealing on them is far superior. As for flex I scoff at that. If its good enough for Hoy, Bauge, Perko et al its will hardly be a problem for you with your 42/16. Also lots of WC singlespeeders still run WI and Middleburn cranks. Your argument is invalid.

Ouch,

You obviously haven't ridden quality outboard BBs (Shimano, Truvativ, CK, Hope). I've only had one outboard BB shit itself. But had 4 internal (2x sealed octalink, 1x white industries, 1x sugino). It's pretty clear outboard BB's have much larger bearings and have a larger/stiffer axle that distributes the force more evenly. And yes, internals are plenty stiff, but you can feel a difference in stiffness. When coming off MTBs (witch mitchy is) it is quite noticeable.

I didn't say internal BBs were worse, there are many valid uses for them.. high end single speeds being the most obvious of them.

I would say my argument wasn't an argument at all, just an explanation of the pros and con's of internal BBs. And for mitchy, I would argue outboard would be better for familiarity/feel/easy of use.

 

[mitchy_]

48/18 is a great ratio. low 70s. Perfect. You'll be fine unless the hills are really big. I used to train on low hilly terrain with that ratio. On the flat I rode 48/15 (mid 80s). You'll be fine. Enjoy it and have a go riding fixed its a good buzz.

i'll see how it goes. the single speed was purely to increase my fitness. i've slowly bumped up the chainring and decreased the cassette size on my other bike, but i wanted something that forces me to get up and pedal if needs be.
i'm waiting for my front brake to arrive before it does anything other than a lap of the block, i'll die fixed and/or with no brakes!

Ouch,

You obviously haven't ridden quality outboard BBs (Shimano, Truvativ, CK, Hope). I've only had one outboard BB shit itself. But had 4 internal (2x sealed octalink, 1x white industries, 1x sugino). It's pretty clear outboard BB's have much larger bearings and have a larger/stiffer axle that distributes the force more evenly. And yes, internals are plenty stiff, but you can feel a difference in stiffness. When coming off MTBs (witch mitchy is) it is quite noticeable.

I didn't say internal BBs were worse, there are many valid uses for them.. high end single speeds being the most obvious of them.

I would say my argument wasn't an argument at all, just an explanation of the pros and con's of internal BBs. And for mitchy, I would argue outboard would be better for familiarity/feel/easy of use.

helps when i have a bunch of mtb BB's, cranks, etc around too!

 

[wombat]

helps when i have a bunch of mtb BB's, cranks, etc around too!

Then if you're planning on running FW just yank on the frame until a 130mm hub fits, and run your cranks.

 

[Danny B]

You obviously haven't ridden quality outboard BBs (Shimano, Truvativ, CK, Hope).

Yes I have. Shimano XT and Sram x9/rival level. Both shit themselves relatively fast in wet seaside conditions, faster than the Sugino, Shimano and Tange SQ I have run.

I didn't say internal BBs were worse, there are many valid uses for them.. high end single speeds being the most obvious of them.

I would say my argument wasn't an argument at all, just an explanation of the pros and con's of internal BBs. And for mitchy, I would argue outboard would be better for familiarity/feel/easy of use.

Relax, its a figure of speech dude, but FWIW The bike came with a SQ crankset so whats the advantage of swapping it out with a MTB crankset?! Which will have the wrong BCD for road/track chainrings, not to mention the fact that the chainline will be too far outboard for 120mm rear spacing and your chainline adjustment is limited to what you can do with the BB spacers. This makes no sense.

I was of the understanding that the main driver of outboard BBs was about being able to produce a lighter cranks/BB, as the spindles can be made from lighter material than a internal BB. There is little uptake in track circles with only SRAM producing Ex BB track cranks. Put simply its just not the best tool for the job.

Then if you're planning on running FW just yank on the frame until a 130mm hub fits, and run your cranks.

Ha ha.. :gold:

 

[wombat]

I was of the understanding that the main driver of outboard BBs was about being able to produce a lighter cranks/BB, as the spindles can be made from lighter material than a internal BB.

That and shitty bearing life. That shittiness became was largely down to problems with things like ISIS though, which jammed a big spindle inside a small shell, and left you with seriously small bearings. External bearing BBs can definately be made stiffer than a square taper crank, that's simply a product of the larger spindle, and arguing otherwise is pretty futile. That said, there's obviously implications for chainline and such, and maybe that's too much of a trade off for track use, I wouldn't know.

I do find it suprising that there isn't greater adoption of the external setups and bigger spindles though. As you say, track guys put out crazy bullshit power, so you think they'd be looking for any advantage they can get. I can see why the hipster fixie crowd don't want it, they're just stuck in the dark ages, but I thought it might be more enticing to real racers.

 

[Danny B]

but I thought it might be more enticing to real racers.

I think the main reason is that its unnecessary with regards of weight savings and the benefit of increased stiffness is deemed to be an advantage in theory only (when compared to a top end 144 BCD track crankset (namely Sugino 75 and Shimano Dura Ace - which they all tend to run right now).

Track bikes have the same UCI weight limit as road bikes and so there's no advantage to having superlight cranks, in fact the converse is true, considering that the BB is an excellent place to locate extra weight on a bike.

One recent development that I think you might see adoption of in sprint bikes is tapered steerers. But then again maybe you won't.

 

[wombat]

Is Shimano's adherence to 3pce maybe something to do with NJS as well?

 

[Danny B]

Yes, most probably, with Keirin racing being Japanese and all.

It interesting that Team GB and FES (German National team) are still happy to use Sugino 75s considering there is no doubt that you can get a stiffer carbon crankset and lower bearing friction with ExBBs.

It would seem that the only country to use full carbon cranks and ExBBs is the French with their Look L96s and proprietary cranks. Of course its undoubtedly the most coveted track bike out there at this point in time. Not cheap tho' at $7000+ for a frameset. (and check out the bizzare steerer tube configuaration)

 

[mitchy_]

jagged the crank. S950 with GXP external bottom bracket and ring in the 'little ring' position gives me a perfect chainline.
tried 38/18 as i had a spare 38T ring and thought 48/18 would be ridiculous where i ride, but i spun out very easy... thinking somewhere around 44T would be perfect.

fitted a front brake, does the job. just need to play around with stems and bars to get comfy now. was an interesting first ride, my right thumb kept going to change gears hah.

 

[mitchy_]

well... after trying 38/18 as i had a 38T ring around, then going to 44/18.. i'm now back at 48/18... probably should have listened to Danny in the first place, haha.

there is a few fills i know give me grief on my 38 x 11-25 bike.. but they didn't seem as bad as expected on 44/18? perhaps knowing i have one gear i anticipated the climbs and carried more speed prior. who knows!
will find out how they go at 48/18 tomorrow.

 

[wombat]

My SS is running 39-18 on 23's, which is only going to be a little longer than yours, and it seems to be a pretty good get around gear. Gave me a bit of grief coming out of West Head once but I don't ride hills that much on the roadie anyway.

 

[mitchy_]

I spun out way to easy on 38/18. 48/18 is just that little bit to much, going back to 44 or 46.
This is on 28mm tyres too, although I don't think that makes much difference.

 

[yatseck]

halo Fix-G Track Hubs

hi, anyone has broken axles on the halo fix-g track hubs recently? I broke 3 in the last 18 months. trying to figure out if there is something wrong with my set up or problems with materials/built quality of the hubs. thanks, Jacek.

 

[SMIIISH]

Thought I'd pop in a shameless sell on my fixie here, I'm looking to shift it on quickly!
On an unfortunate side note, this thread has seemed to have lost some of it's momentum over the last couple years. :yuck:

http://www.rotorburn.com/forums/sho...ixie-Single-Speed-Steel&p=2919181#post2919181