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-   -   CRAAAAAZY question, need help. (https://www.bikeforums.net/singlespeed-fixed-gear/801818-craaaaazy-question-need-help.html)

positron 02-29-12 05:29 PM

CRAAAAAZY question, need help.
 
howdy,

post alot in other subforums, first time posting here... used to ride fixed wheel audax quite a bit years ago when I lived in England, decided I miss it.

anyway, heres the skinny:

I want to build one wheel for a Kogswell PR frame using a 135 rear (MTB) disk hub with a bolt on fixed cog.

I want the option of being able to use the cassette sometimes too by adding a derailleur and flipping the wheel around.

SO: casette one side, fixed cog bolted to disk other side... possible? Anyone want to measure an MTB disk rotor to see what the potential chainline would be?

PS, not interested in hearing why its a stupid idea, or why i shouldnt do it, just want to know if it will work... Im hoping that the disk mount cog would be around 54mm chainline, meaning i could ride fixed with a chainring in the outer position of an MTB triple crank. Anyone done such an ill-advised and foolish thing?

TIA :thumb:

Jaytron 02-29-12 05:38 PM

Is there even a hub that has the capability to do what you are describing? Probably not, because it makes no sense to do....

Santaria 02-29-12 05:38 PM

You'll have to search, but there was a recent thread about bolt-on cogs where peeps were riding with canti's on the rear because you eliminate the ability to use the disc (obviously). Seems that any traditional frame with studs on the rear would work.

I took a moment, feeling friendly, and remembered the name of the company. Velosolo.

My always preference on non-racing wheels are salsa delgado hubs laced to surly new hubs (pretty much the stock buildup for Surly Karate Monkey). I run them on my KM and my Fixed-gear Diablo (Handsom Devil).

Jaytron, oddly, they do exist.

Jaytron 02-29-12 05:39 PM

But I mean to run fixed/cassette, you would also have to break and change the chain every time you flipped over.

Santaria 02-29-12 05:42 PM


Originally Posted by Jaytron (Post 13915457)
But I mean to run fixed/cassette, you would also have to break and change the chain every time you flipped over.

True. You will also have a derailleur hanging there in space when in fixed mode. You might want to make sure there isn't a contact problem with it being there. If you're talking about running some form of a convertible where you can remove your chain, DR and just flip the wheel, then it would work. Otherwise, you're going to be putting a lot of money out there in space, exposed to contact and destruction.

JohnDThompson 02-29-12 05:43 PM


Originally Posted by positron (Post 13915414)
I want to build one wheel for a Kogswell PR frame using a 135 rear (MTB) disk hub with a bolt on fixed cog.

I want the option of being able to use the cassette sometimes too by adding a derailleur and flipping the wheel around.

SO: casette one side, fixed cog bolted to disk other side... possible? Anyone want to measure an MTB disk rotor to see what the potential chainline would be?

PS, not interested in hearing why its a stupid idea, or why i shouldnt do it, just want to know if it will work... Im hoping that the disk mount cog would be around 54mm chainline, meaning i could ride fixed with a chainring in the outer position of an MTB triple crank. Anyone done such an ill-advised and foolish thing?

TIA :thumb:

What are you going to do about the derailleur when you're riding the fixed side, and where will you get the additional chain length when you're riding the derailleur side?

positron 02-29-12 05:51 PM


Originally Posted by Jaytron (Post 13915448)
Is there even a hub that has the capability to do what you are describing? Probably not, because it makes no sense to do....

any mtb hub with a 6bolt disk rotor mount... see: shimano wtb, others.


moving on.

positron 02-29-12 05:58 PM


Originally Posted by JohnDThompson (Post 13915476)
What are you going to do about the derailleur when you're riding the fixed side, and where will you get the additional chain length when you're riding the derailleur side?

right, so obviously it wouldnt be set up at the same time... sorry if that warn't clear.

I would have two chains, one long(gears), one short (fixed).

most of the time would be ridden fixed here in the city.

When I want to ride out and go camping in the mtns. nearby I would pull the wheel, change the chain, screw the derailleur on, hook up the friction shifter.

the bike has paul cantis already, no disk brakes...
it would take 15 mins to swap from geared to fixed or vice versa, I just dont want to have to build two wheels...

IM mainly worried about where the chainline would be if I bolted a boone ti cog onto the disk mount. Most people do this with a front hub with spacers... I want to use the cassette hub.

positron 02-29-12 06:01 PM


Originally Posted by Jaytron (Post 13915457)
But I mean to run fixed/cassette, you would also have to break and change the chain every time you flipped over.

Sram powerlink... takes two seconds.

Jaytron 02-29-12 06:02 PM


Originally Posted by positron (Post 13915560)
Sram powerlink... takes two seconds.

Two of them? to resize the chain?

Edit:Nvm, says you're going to have two chains.

I would just have a dedicated fixed gear tbh.

positron 02-29-12 06:06 PM


Originally Posted by Jaytron (Post 13915567)
Two of them? to resize the chain?

Edit:Nvm, says you're going to have two chains.

I would just have a dedicated fixed gear tbh.

I would too, but I live in a shoebox, and the frame is spaced 135 for 650B wheels, so its not like I can just pick one up cheap from the local latte-hustler off CL.

Jaytron 02-29-12 06:09 PM


Originally Posted by positron (Post 13915583)
I would too, but I live in a shoebox, and the frame is spaced 135 for 650B wheels, so its not like I can just pick one up cheap from the local latte-hustler off CL.

If you had a vertical stand to hold both bikes, is just having two completely separate bikes out of the question? n+1!

osiris419 02-29-12 06:13 PM

I'm pretty sure, not positive, you will have to break down the hub and change around the spacers anytime you want to flip the flop. You'll probably be better off with two separate wheels, or bikes.

positron 02-29-12 06:20 PM


Originally Posted by Jaytron (Post 13915598)
If you had a vertical stand to hold both bikes, is just having two completely separate bikes out of the question? n+1!

Ive thought about it, alot... but im actually trying to get rid of Stuff right now: simplify and all that the only @$$hole on BF doing N-1...
The idea of a double-use bike seems nice to me, and something makes me want to try an unconventional build for 'WTF thats stupid' value. I think it came from looking at sheldons left-hand drive bike.

wait a second: bolt on cog.. left hand drive.... I could just pull and flip the crankset hahhaha now thats a stupid idea...

positron 02-29-12 06:25 PM


Originally Posted by osiris419 (Post 13915613)
I'm pretty sure, not positive, you will have to break down the hub and change around the spacers anytime you want to flip the flop. You'll probably be better off with two separate wheels, or bikes.

plus redish the wheel... yeah, thats not gonna happen- I wish I could find the center- disk rotor distance of a rear hub online. I know its standardized, just don't know if its within the realm of any 'normal' chainline

adriano 02-29-12 06:31 PM

ive been planning the same thing for quite some time. its a 50mm plus chainline.

positron 02-29-12 06:32 PM

well, thanks anyway all,
Ill check this again in the future, so If anyone has, or can take the measurements I'm talking about, please post em.

cheers.

positron 02-29-12 06:35 PM


Originally Posted by adriano (Post 13915708)
ive been planning the same thing for quite some time. its a 50mm plus chainline.

Ahhh bichin,

a "standard" MTB triple has the outer chainring at 54mm, so that might be doable!

Lets hear it for Bal'mer! Craaaazy dudes like this guy ^^ and John Waters.... I raise a pitcher of Natty-Bo to you sir.

M_S 02-29-12 06:37 PM

Ask in the ss section of MTBR. Lots of tomicog users there, and someone should know the chainline.

Also, no, of course you don't need to redish the wheel, ever. Why would anyone think that? It's amazing how willing people are to offer up opinions on things they know nothing about. For what it's worth I think your idea is fine.

Cynikal 02-29-12 07:05 PM

I think a simpler solution would be a separate IHG rear wheel. You could use the fixed hub as a SS as well. I know it's not exactly what you are looking for but it may meet you space needs.

markaitch 02-29-12 07:28 PM

i have a singlespeed 29er that i run fixed with a tomicog pretty often. the ss side of my rear hub is a splined cog & spacers on a freehub & i have a ss crankset with the ring on the inside.

unfortunately, i lent that bike to my kid & have not been able to get him to return it so i can't measure but if i remember correctly, i think it is a 50mm chainline when it is set-up ss. when i am in the mood to go fg mtbing i just put the tomicog on, flip the wheel, & hit the trails. it is not a perfect chainline but it has never been a problem.

op...as long as you have the chain & derailler thing figured out, there's no reason your plan should not work out easily.

M_S is right, go ask about this over in the ss forum on mtbr where you will likely get better info than suggestions to buy a 2nd wheel or a vertical stand & another bike ;)

have fun & good luck...

adriano 02-29-12 07:39 PM

so this happened: http://baltimorebohemians.com/

ball so hard.

positron 02-29-12 07:52 PM


Originally Posted by markaitch (Post 13915954)
op...as long as you have the chain & derailler thing figured out, there's no reason your plan should not work out easily.

This is what I was hoping to hear. Ill make it work, thanks boss.

positron 02-29-12 07:53 PM


Originally Posted by adriano (Post 13916001)
so this happened: http://baltimorebohemians.com/

ball so hard.

So I live out in Denver now, but I gotta get a shirt.... thats awesome.

positron 03-01-12 11:38 AM

Found it:
http://www.flickr.com/photos/7935825@N04/2973503413/

52-53 mm.

within realm of the outer position of MTB triple... miller time!


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