Advertise on Bikeforums.net



User Tag List

Page 1 of 2 12 LastLast
Results 1 to 25 of 33
  1. #1
    He drop me Grasschopper's Avatar
    Join Date
    Jul 2004
    Location
    Central PA
    My Bikes
    '03 Marin Mill Valley, '06 Cannondale Rush, '02 Eddy Merckx Corsa 0.1, '07 Bottecchia Euro Sprint Tour Comp Elite Pro 1000
    Posts
    11,436
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Can I run a std road double crank set?

    Ok so I am wondering if I can run a std road double crankset on a fixed gear and get a normal chain line. I am thinking my Merckx (Corsa 0.1) should be a fixed gear rather than a geared bike...it has semi horiz dropouts so I have that covered and it is spaced at 130mm if that matters.

    Thanks for any help.
    The views expressed by this poster do not reflect the views of BikeForums.net.

  2. #2
    LF for the accentdeprived
    Join Date
    May 2005
    Location
    Budapest, Hungary
    Posts
    3,550
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Too many variables.
    If by "normal" you mean 42mm, then probably not. 45 is doable. If you don't run a flipflop, you should be ok with 45.

    The above applies if you want to run the ring on the outside. If you're willing to put it inboard, you can get 42 (providing that your frame doesn't veto it).
    Quote Originally Posted by dutret
    Do you deny that you are clueless or do you just think that "moron" didn't need to be tacked on there?
    Bike on flickr and on FGG

  3. #3
    He drop me Grasschopper's Avatar
    Join Date
    Jul 2004
    Location
    Central PA
    My Bikes
    '03 Marin Mill Valley, '06 Cannondale Rush, '02 Eddy Merckx Corsa 0.1, '07 Bottecchia Euro Sprint Tour Comp Elite Pro 1000
    Posts
    11,436
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Ok I ride geared bikes a ton but know little to nothing about fixies here. What is the 42mm and 45mm measurement?

    The crank is a 2007 Campagnolo Centaur UT
    The views expressed by this poster do not reflect the views of BikeForums.net.

  4. #4
    LF for the accentdeprived
    Join Date
    May 2005
    Location
    Budapest, Hungary
    Posts
    3,550
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Centre of the chainring from the centre of the frame. 42 is the track standard so that's the way track hubs are set up. But then they're also 120mm wide, so you can compensate for the difference when you space your hub up from 120. There is a boatload of possible solutions. There are 130 hubs as well, which would be easier to install but it'd be trickier to play w/chainline. Paul hubs have a wider chainline to begin with.
    Quote Originally Posted by dutret
    Do you deny that you are clueless or do you just think that "moron" didn't need to be tacked on there?
    Bike on flickr and on FGG

  5. #5
    lunatic fringe Dogbait's Avatar
    Join Date
    Aug 2005
    Location
    Miles from Nowhere, Columbia County, OR
    My Bikes
    1980 Schwinn World Sport, 1982 Schwinn Super Le Tour, 1984 (?) Univega Single Speed/Fixed conversion, Kogswell G58 fixed gear, 1987 Schwinn Super Sport
    Posts
    1,111
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    First, here is a ton of info on fixed gear bikes:

    Fixed Gear Articles

    ... and more specifically about chainline:

    Chainline

    You can also adjust the chainline by using a different length bottom bracket or by using a spacer behind the drive side bottom bracket cup. Measure first, then adjust. Or, as the carpenters say, "measure twice, cut once".

  6. #6
    Senior Member
    Join Date
    Sep 2006
    Location
    Van BC
    Posts
    3,744
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Fixed gear chainline can seem really confusing and technical at first but like some guy on this forum once said, it's really cave man stupid. You want the cog and the chainring to be in line with each other. Find a rear hub that fits your 130mm spacing. It will put the cog someplace or other. Then find a bb with a spindle length that puts your chainring in line with wherever the cog is. The real moron method used by lots of people who build conversions (including me) is to get two bb's; the first one will not work, but you can see how far out it is and use that measurement when buying the second one. The beauty of conversions is, often the frame you're starting with comes with a bb that can assume the "sacrificial" role.
    Last edited by mander; 12-16-06 at 12:55 PM.

  7. #7
    Geek Extraordinaire sivat's Avatar
    Join Date
    Feb 2006
    Location
    Long Beach, CA
    My Bikes
    Bianchi Advantage Fixed Conversion; Specialized Stumpjumper FS Hardtail
    Posts
    1,769
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The simple answer is yes, you can. You'll probably need a new bottom bracket to get the chainline right though. Here is the easy way to do it:
    1. with the double crankset on the bike, measure the distance from the center of the seat tube to the center of each of the rings. (Or measure from the edge of the seat tube to the rings, then add half the diameter of the seat tube, it a little easier that way).
    2. If either of the rings measures within 2 mm or so of 42mm, just put the ring in that position, and you'll be fine. Really, anything up to 5mm is acceptable, but the closer it is to 42mm, the quieter and smoother the drivetrain will be.
    3. if you're not that lucky and neither ring is close enough, or you just don't like the look of running a single chainring on the inside position, pull the cranks and measure the bb spindle. If you have the original bottom bracket, you might be able to find the length here.
    4. Subtract twice the difference of where your chainring is from where you want it to be from the bb length you have now, and try to get a bb in that size. That was probably hard to follow. If you didn't understand, let me know.

    Also, not all bottom brackets are symmetrical. The drive side on a 110mm bb is the same as the drive side on the 107mm bb. The difference is on the non-drive side. Unfortunately, theres no easy way to find this out, but I am trying to build a spreadsheet of bb sizes to make it easier.
    I'd rather have a bottle in front of me than a frontal lobotomy.

    Sintesi Conversion Serotta Track

  8. #8
    Banned.
    Join Date
    Oct 2004
    Posts
    4,418
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Yes, it will work fine.

  9. #9
    Packfodding 3 caloso's Avatar
    Join Date
    Jul 2002
    Location
    Sacramento, California, USA
    My Bikes
    Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper
    Posts
    29,886
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Yes, it will work fine, but depending on your frame, you may be limited to the chainring you can run. I have a 42t chainring mounted on the inside of a double crankset and I have maybe 2 mm clearance at the chainstay. I doubt I could put a 44 on there without messing with moving the rear cog out. That would be a huge can of worms.
    Cyclists of the world, unite! You have nothing to lube but your chains!

  10. #10
    Cornucopia of Awesomeness baxtefer's Avatar
    Join Date
    Oct 2004
    Location
    not where i used to be
    Posts
    4,847
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    guys, he's trying to do it with the new Campy Ultra-Torque cranks. He can't change out his BB spindle to futz with chainline.

    install the cranks then measure the position of both rings.
    the inner ring will likely be the closest one to 42mm. if it's within ~2mm then use it.

    if neither is close to 42mm then get a different crank.

    though another option would be to get hubs that have a non-standard chainline. like pauls' (44mm)
    {o,o**
    |)__)
    -"-"-

    O RLY?

  11. #11
    spinspinspinspin fatbat's Avatar
    Join Date
    Nov 2004
    Posts
    880
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by baxtefer
    guys, he's trying to do it with the new Campy Ultra-Torque cranks. He can't change out his BB spindle to futz with chainline.

    install the cranks then measure the position of both rings.
    the inner ring will likely be the closest one to 42mm. if it's within ~2mm then use it.

    if neither is close to 42mm then get a different crank.

    though another option would be to get hubs that have a non-standard chainline. like pauls' (44mm)
    +1 on the pauls- wider chainline should make your life a lot easier in this respect.
    a radar blip, an empty clip, post-nasal drip, and kung fu grip

  12. #12
    He drop me Grasschopper's Avatar
    Join Date
    Jul 2004
    Location
    Central PA
    My Bikes
    '03 Marin Mill Valley, '06 Cannondale Rush, '02 Eddy Merckx Corsa 0.1, '07 Bottecchia Euro Sprint Tour Comp Elite Pro 1000
    Posts
    11,436
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thaks for the input guys...and Baxter is right...integrated spindle BB so no change is possible.

    The outer ring is at 45mm and the inner ring is at 36mm or 37mm.

    I was thinking of using a 130mm IRO hub (really looking at the set). It looks liek they are just adding spacers and not changing the actual hub body...is that correct...this an ok hub to go with?
    The views expressed by this poster do not reflect the views of BikeForums.net.

  13. #13
    Cornucopia of Awesomeness baxtefer's Avatar
    Join Date
    Oct 2004
    Location
    not where i used to be
    Posts
    4,847
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    the 130mm IRO hub is just a 120mm with 5mm of spacers on either side
    {o,o**
    |)__)
    -"-"-

    O RLY?

  14. #14
    yo yo yo yo yo
    Join Date
    Nov 2005
    Location
    delaware
    Posts
    2,518
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    pauls are 44 and levels are 45 if it matters that much to you

  15. #15
    I like turtles mascher's Avatar
    Join Date
    Dec 2004
    Location
    Philly
    My Bikes
    Pink Nightmare (RIP), Kona Smoke fixed conversion, Surly Steamroller, Schwinn hardtail, Raleigh singlespeed mtb conversion (soon to be RIP), Green Road Biest
    Posts
    898
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The idea of buying different hubs for a 2mm difference in chainline seems crazy to me. I won't call the chainline police if your hub wants a 42mm chainline and the outside of your crank kicks it 45mm. I'm running a 107mm Shimano bb with a 600 crank and the ring on the outside with a 45mm chainline on a Kogswell hub without a problem, save the the chainring bolts are very close to the stays. I don't find it noisy or anything less than smooth.

    Even with a Miche crank and bb and Miche hubs, I still don't have a perfect chainline on a Steamroller out of the box.

  16. #16
    LF for the accentdeprived
    Join Date
    May 2005
    Location
    Budapest, Hungary
    Posts
    3,550
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I know I wouldn't run a drivetrain w/chainline that's 3mm off for sure. Especially not if I have the oppurtunity to get it right because I haven't bought the parts yet.

    Are integrated cranks that narrow? That's 7 mm in compared to standard sqare taper stuff...

    I'd look into the Level thing. If you don't mind the proprietary system and don't want to run a freewheel, you're golden. Otherwise, just respace an IRO if you don't want to run a flipflop. Actually, I think you can get pretty good chainline if you run a freewheel on the other side. Freewheels are wider than cogs.
    Quote Originally Posted by dutret
    Do you deny that you are clueless or do you just think that "moron" didn't need to be tacked on there?
    Bike on flickr and on FGG

  17. #17
    I like turtles mascher's Avatar
    Join Date
    Dec 2004
    Location
    Philly
    My Bikes
    Pink Nightmare (RIP), Kona Smoke fixed conversion, Surly Steamroller, Schwinn hardtail, Raleigh singlespeed mtb conversion (soon to be RIP), Green Road Biest
    Posts
    898
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by LóFarkas
    I know I wouldn't run a drivetrain w/chainline that's 3mm off for sure. Especially not if I have the oppurtunity to get it right because I haven't bought the parts yet.
    Haven't bought, sure.

    Why wouldn't you though? How off would you run, and why?

  18. #18
    LF for the accentdeprived
    Join Date
    May 2005
    Location
    Budapest, Hungary
    Posts
    3,550
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Preferably <1mm. Mostly just to "do it right". If your chainline is off, the chain will 1) be noisier 2) wear faster 3) be more likely to fall off. You also lose some efficiency.

    These are small factors at <3mm, but why bother going singlespeed if you're going to put up with the drivetrain problems of multispeed bikes?
    Quote Originally Posted by dutret
    Do you deny that you are clueless or do you just think that "moron" didn't need to be tacked on there?
    Bike on flickr and on FGG

  19. #19
    I like turtles mascher's Avatar
    Join Date
    Dec 2004
    Location
    Philly
    My Bikes
    Pink Nightmare (RIP), Kona Smoke fixed conversion, Surly Steamroller, Schwinn hardtail, Raleigh singlespeed mtb conversion (soon to be RIP), Green Road Biest
    Posts
    898
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by LóFarkas
    Preferably <1mm. Mostly just to "do it right". If your chainline is off, the chain will 1) be noisier 2) wear faster 3) be more likely to fall off. You also lose some efficiency.

    These are small factors at <3mm, but why bother going singlespeed if you're going to put up with the drivetrain problems of multispeed bikes?
    I'm for all those reasons. It's hard to tell on this board for proper/ideal/nitpicky/anal stuff like chainline where people are trying to dial in to the nth degree (41.5mm just isn't *good* enough) or if they're trying to get something ramshackle to work or are a first timer who wouldn't know the difference, and everyone's somewhere in between on something or other.

    I'm mostly in the latter faction out of ideology - something in me *likes* being a little bit off what you're supposed to do or making stuff work that's not supposed to against all odds. I like having a little more slack in my chain than perfect so that when I balance I have that half cm of non-engagement to float a bit, say, and I think conversions are cooler than fixed specific road frames, and I especially love stuff like your version of the project of the disk hub conversion. And I made several posts here about bbs and cranks because I didn't know whether or not my bike would blow up if I just did what I thought would work.

    As for chainline, agreed and disagreed - wear and noise, meh, and if you're dropping chains, well, something's more wrong than a mm or two of chainline. I'd consider multispeed drivetrain problems to be: missed shifts, tuning deraileurs (and throwing them into your spokes), wearing out my favorite gear and needing a whole new cassette, breaking shifters that have more moving parts than a car (and cost almost as much), and not getting to experience the fun of a fixed gear bike or the carefreeness of a SS. mms of chainline I think for me is the most overthought and least significant part of building up a fixed gear bike. I guess it's also practically the only thing you have to think about, so touché.

  20. #20
    Senior Member mattface's Avatar
    Join Date
    Sep 2005
    Location
    Montpeculiar, VT
    My Bikes
    Soma Rush, Fuji Cross, Raleigh Technium Mtn Bike, Ross 10 speed with Shimano 600.
    Posts
    3,951
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I can't believe the inner ring is 8-9 mm inboard of the outer ring. 3-4mm is closer to what most doubles look like. if the outer ring is at 45mm, the inner ring should be around 41-42. The inner ring on my 105 9-speed crank measures just about 41-42, and the outer measures about 45.

    I know it doesn't look as slick to run the chainring on the inside of the spider, so with that setup, you get to choose between perfect chainline, or aesthetics. Another option to improve the aesthetics would be to run a bash ring on the outside of the spider. if you can't find a bash ring in the right BCD (135?) grind the teeth off an old chainring.

  21. #21
    He drop me Grasschopper's Avatar
    Join Date
    Jul 2004
    Location
    Central PA
    My Bikes
    '03 Marin Mill Valley, '06 Cannondale Rush, '02 Eddy Merckx Corsa 0.1, '07 Bottecchia Euro Sprint Tour Comp Elite Pro 1000
    Posts
    11,436
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I will measure it again...maybe I was smoking crack or something.

    Thanks for all the feedback guys. So the Paul's and Level's have those numbers with a 130mm spacing? Since I don't have anything (well other than the bike) I can get whatever.

    FWIW here is the bike as she sits now:
    The views expressed by this poster do not reflect the views of BikeForums.net.

  22. #22
    Cornucopia of Awesomeness baxtefer's Avatar
    Join Date
    Oct 2004
    Location
    not where i used to be
    Posts
    4,847
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    that bike needs gears.
    leave it as it is.
    {o,o**
    |)__)
    -"-"-

    O RLY?

  23. #23
    tarck bike.com exile 666pack's Avatar
    Join Date
    Jul 2006
    Location
    lancaster, pennsylvania
    My Bikes
    bfssfg iro--black.
    Posts
    2,058
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by baxtefer
    that bike needs gears.
    leave it as it is.
    + cokehead ex-girlfriends.
    that thing is too nice to convert. if you want a nice fixie just get a track bike.

  24. #24
    Geek Extraordinaire sivat's Avatar
    Join Date
    Feb 2006
    Location
    Long Beach, CA
    My Bikes
    Bianchi Advantage Fixed Conversion; Specialized Stumpjumper FS Hardtail
    Posts
    1,769
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I was told by an experienced track mechanic that a chainline within 5mm is just fine. If you don't mind spending the extra cash to get hubs with a 44-45mm chainline, go for it. Otherwise, the 3mm won't really matter.

    P.S. Nice bike.
    I'd rather have a bottle in front of me than a frontal lobotomy.

    Sintesi Conversion Serotta Track

  25. #25
    Packfodding 3 caloso's Avatar
    Join Date
    Jul 2002
    Location
    Sacramento, California, USA
    My Bikes
    Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper
    Posts
    29,886
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Leave it geared. For Eddy's sake.
    Cyclists of the world, unite! You have nothing to lube but your chains!

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •