Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

Lightweight Square Taper BB

Old 10-05-18, 02:09 PM
  #26  
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Originally Posted by 1speed4me View Post


I'm chill. It is my first fixed conversion, not my first fixed gear bike. I like older stuff, so this is what I chose to build. I'm fully aware of the negatives of a build like this, but I'm trying to offset them wherever possible and thereís something about having nice parts on such a domestic frame that appeals to me. I have a lot of bikes, but this one is by far the most fun to ride, so it gets the most action. I could even possibly see myself selling off the rest of my herd and having this as my only bike... So I want to make it the best it can be, within my budget of course and it has to stay an attractive, cohesive piece in my eyes. I know a BB isn't a ton of weight savings, and I understand all of the reasons why a lighter one won't make a difference. My Ti eggbeater 11's probably didn't make a damn bit of difference compared to the 2's I had on there before, but I like them, they make me happy, that's all that matters on my bike. I know you guys probably see a ****ty old Schwinn, which it is, but I dig it and a cheap $20 BB just seems like the wrong thing to do.
No one said it was a ****ty schwinn, nor did anyone tell you to get a $20 BB. In fact, I think its a good looking bike!
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Old 10-05-18, 05:52 PM
  #27  
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Originally Posted by IAmSam View Post
Its a nice enough old frame, so if that along with whatever money you waste...errr...throw at it to make it lighter, is what makes you happy...enjoy! There are plenty of good, and even somewhat light, new modern sealed 68mm, JIS BBs for you to choose from, at decent prices.

But...you have got to get the right spindle length and that is going to be rough for you. That 147mm length on your current BB that you mentioned, however you got it, makes no sense. I'd say you should use the Google to check out what BB length your Super Maxy was originally specced for. However IIRC there were several versions so it might be hard to come up with a single, exact number, but at least that gives you a starting point.

Unless you can measure your existing BB better, you are not going to have it easy. Good luck - you are going to need it
Yeah, right after I reassembled it I realized that I probably measured it wrong by including the length of the threads. Iíll try to get back in there this weekend and measure it properly.

Is this JIS taper?
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Old 10-05-18, 06:15 PM
  #28  
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Originally Posted by veganbikes View Post
Here are good quality ones that may or may not be lightweight: Phil Wood, IRD Defiant/QB-95, SKF and White Industries. Those are all high quality square taper BBs and I will take better bearings and longer life then weight anytime.

If you want to save weight, remove the Tuggnuts, grab a carbon fork from say Wound Up Composites because they still make a 1" threaded carbon fork. Or you can do a conversion and get a 1" threadless headset from say Cane Creek or Chris King or Phil Wood and then do a Ritchey Comp fork (I think IRD or Soma or Tange basically one of the companies related to Merry Sales Co. also makes a 1" threadless carbon fork). This will allow you to use a lighter weight threadless stem (you might need to shim it if you are using a 1 1/8 stem) then maybe look at a shallower section wheel, a lighter seatpost and maybe a lighter bar either carbon or titanium.

If you wanted to keep the current set up then I would find a lighter weight quill stem and seatpost and swap out bars and of course shallower section wheels.

However me I would probably keep the set up as is and ride the damn bike. It is a good looking set up. I would change wheels and tires for myself to like a H+Son TB14 or similar rim and a tan wall tire and maybe some polished hubs (Phil Wood would look the best but Paul are just fine by me)
I also value long term reliability over lightness, Iím hoping to find the best balance of both.

The Tuggnuts (actually Hurdy Gurdyís) keep the wheel in place and allow me the fine adjustment that I need to fit the 32ís (itís very, very close between the chainstays). They are heavy, I donít like them, but they do work very well and I wouldnít trust the wheel to stay where I left it without them. The forward dropouts are the thing that I dislike the most about this bike but itís a sacrifice that I made.

Thanks for sharing all of those fork options! I had no idea those even existed. Iíll definitely keep them in mind.

Along with the tires I also have some Conti race 28 tubes coming to try out, so I will be loosing a fair amount of rotational weight.

Last edited by 1speed4me; 10-05-18 at 06:23 PM.
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Old 10-05-18, 06:48 PM
  #29  
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Originally Posted by 1speed4me View Post
I donít like them, but they do work very well and I wouldnít trust the wheel to stay where I left it without them.
Then you need better quality axle nuts and probably need to work on your technique for mounting your wheel and setting chain tension. Iím not saying ditch the chaintugs, but thatís not their purpose. I understand exactly what youíre talking about in fitting larger tires. I actually run a 70s era converted road frame with 32mm tires myself, but you shouldnít need any chaintugs to help keep an axle in place. Also, I personally find forward dropouts easier for everyday use than track style fork ends, but to each their own.

one thing you could use are traditional drop out screws that thread into the back face of the dropout. Iím sure your frame has threaded holes for them. You can buy new screws from Velo Orange. The type that would have been originally used on your bike, for quickly setting wheel position. Thatís what I use on my bike and it makes setting my wheel very quick and easy.





Last edited by seamuis; 10-05-18 at 06:53 PM.
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Old 10-05-18, 09:16 PM
  #30  
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[QUOTE=Scrodzilla;20600814]People worrying about the weight of a ****ing bottom bracket.

Go take your laxative... then jump into your buggy and go to the big box store and buy a life.
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Old 10-05-18, 09:44 PM
  #31  
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Originally Posted by 1speed4me View Post



Yeah, right after I reassembled it I realized that I probably measured it wrong by including the length of the threads. Iíll try to get back in there this weekend and measure it properly.

Is this JIS taper?
I don't know BBs well enough to eyeball the spindle type, but yeah, measure it without the threaded portions to get the spindle length you need. Someone in the mechanics forum could maybe tell you if it's JIS. Or a good bike shop if you have one nearby.
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Old 10-06-18, 07:11 AM
  #32  
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I had one like this but not a Sugino. The "size code" listed on Sheldon's site was stamped on the spindle (scroll down to "Japanese Bottom Bracket Spindles, Traditional Cup And Cone Type"). https://www.sheldonbrown.com/bbsize.html If you want to stick with that type, you can get a replacement here: https://www.sjscycles.co.uk/tapered-...-cone/?geoc=US, or get a symmetrical equivalent cartridge BB.


Your BB appears to weigh 455g so even a Tange or Shimano at 300g... well, I am not going to argue about the weight. I agree with veganbikes where in one of his responses he suggested some good replacements. http://www.equusbicycle.com/bike/sug...hure56%201.pdf
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Old 10-06-18, 11:18 AM
  #33  
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Originally Posted by seamuis View Post
Then you need better quality axle nuts and probably need to work on your technique for mounting your wheel and setting chain tension. Iím not saying ditch the chaintugs, but thatís not their purpose. I understand exactly what youíre talking about in fitting larger tires. I actually run a 70s era converted road frame with 32mm tires myself, but you shouldnít need any chaintugs to help keep an axle in place. Also, I personally find forward dropouts easier for everyday use than track style fork ends, but to each their own.

one thing you could use are traditional drop out screws that thread into the back face of the dropout. Iím sure your frame has threaded holes for them. You can buy new screws from Velo Orange. The type that would have been originally used on your bike, for quickly setting wheel position. Thatís what I use on my bike and it makes setting my wheel very quick and easy.

To tell you the truth, I haven't even tried it without the tensioners. This fixed gear is the third forward dropout/mulit speed bike that I've converted to single speed, the others both needed the Hurdy Gurdy to keep the drive side from pulling forward. I expected this to have the same issue so just I built it with two from the start. My dropouts do not have the threaded holes in them. I'll try it without the tensioners sometime.
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Old 10-06-18, 11:32 AM
  #34  
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Whether it makes sense in everyone's eyes or not, you should be able to achieve some decent weight savings with your bottom bracket. A nutted spindle like yours will be solid all the way through, whereas a hollow spindle is lighter without giving up much (if any) strength. And the aluminum cups on higher-end bottom brackets save additional weight. On my rando bike, I went from a 286g Shimano UN55 to a 247g Tange-Seiki 7922, and that is in spite of going from a 107mm spindle to a 118mm spindle for a different crankset! So if you're not changing the length, you can do even better.
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Old 10-07-18, 05:56 PM
  #35  
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No worries. Happy to help!

Phil Wood made a Ti/Magnesium BB at one point and I think WI did a full ti as well (and might still). My SKF unit I don't feel like weighed a ton but it went into a touring bike and it was so long ago and the bike lost weight from the previous touring bike with smaller wheels.

There is still a decent number of great options for 1" in both threaded and threadless not so much for mountain bikes (at least not in quality) but plenty of road bikes. There is a small part of me that wants to run a 1" threadless fork on my Phil Wood Frame but it is an original PW frame from the Apple VeloXS race team so I would rather not change it too much because it looks good as is.

@seamuis had some excellent ideas as far as getting rid of the tuggnuts or hurdy gurdys whatever they call them these days.

@Aladin Scrod probably has more life in one hair on his chain then you will have in your entire life. Though as I write this I realize he does own his own shop so maybe that is not wholly true but his point is valid. People worry so much about weight on everything and forget to ride. "I can shave a milligram from my bike if I use plastic bolts on my bottle cages" is a really dumb ideal that many people follow. I get it lightweight bikes are fun but obsessing over weight can just get silly at points. For UCI races you have to be over a certain weight to ride the bike and some pros have to put weights in their bikes to make them legal so why not just build a weight appropriate bike instead of weighing down your too lite bike.
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Old 10-07-18, 08:32 PM
  #36  
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Lot of butt hurt in this thread. I second taking laxatives to squeeze out extra weight, then go buy a nice cartridge BB with hollow spindle and aluminum cups as suggested. Wonít break the bank and you can enjoy years of trouble free use. One of the nicer conversions Iíve seen looks good
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Old 10-07-18, 08:44 PM
  #37  
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Originally Posted by REDMASTA View Post
One of the nicer conversions Iíve seen looks good
True that! I once had the opportunity to buy a chromed Schwinn Voyageur and now regret I didn't snag it.
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Old 10-07-18, 08:57 PM
  #38  
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Thanks for the kind words! I know itís not everyoneís first choice, but I have a problem when it comes to old original paint black Schwinn's

My Compass tires arrived, still waiting on the tubes. I work full time and take classes so I haven't had an opportunity to measure my spindle again, much less research exactly what I need and where to find it. I'll get there.

Thanks for the help, I genuinely do appreciate it!

Last edited by 1speed4me; 10-07-18 at 10:47 PM.
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Old 10-10-18, 08:11 PM
  #39  
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I suggest Action-Tec titanium bb. They are located in SoCal https://www.actiontec.us/index.htm
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Old 10-10-18, 09:19 PM
  #40  
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Is Action Tec still around and selling stuff? I know the website is up but it doesn't look like it has any updates for 11 speed stuff and more modern standards. Would love a Ti Chainring.
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Old 12-20-18, 02:02 PM
  #41  
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Apologies for forgetting this thread, my father passed away a couple months ago and my head is still pretty messed up from that. I haven't even been on my bike since then and that is making me feel even ****tier, the PNW winter weather isn't helping the matter. But, I've gotta keep pushing forward...

I decided to go ahead and upgrade the crankset as well, so in keeping with the vintage theme I found a Sugino Super Mighty (144bcd) and I'll be using the 42t drilled inner chainring that came standard on it. Just like my previous combo, I ditched the outer ring in favour of a BBG bash guard and detailed the arms in black.

Originally Posted by ThermionicScott View Post
Whether it makes sense in everyone's eyes or not, you should be able to achieve some decent weight savings with your bottom bracket. A nutted spindle like yours will be solid all the way through, whereas a hollow spindle is lighter without giving up much (if any) strength. And the aluminum cups on higher-end bottom brackets save additional weight. On my rando bike, I went from a 286g Shimano UN55 to a 247g Tange-Seiki 7922, and that is in spite of going from a 107mm spindle to a 118mm spindle for a different crankset! So if you're not changing the length, you can do even better.
I finally properly measured my current BB spindle, looks like I'm right about 125mm. I wouldn't mind adding a few extra mm's for chain stay clearance on future possible upgrades. I also need it to work correctly with the Super Mighty square taper crank (whatever type square taper that is). I like the idea of aluminium cups. Any recommendations on where to find/compare/buy bottom brackets like this? Thanks again-
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Old 12-20-18, 02:04 PM
  #42  
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Old 12-20-18, 11:12 PM
  #43  
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Sorry to hear about your father passing. Losing parents sucks. As much as I tell people I have gotten over my mom passing 13 years ago I haven't and it pretty badly screwed me up but life does go on and be thankful you are still kicking around!

Those cranks do look quite nice, though that is pretty much what Sugino does make nice looking cranks! Wish they would do some vintage repros like these.
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Old 12-21-18, 02:31 PM
  #44  
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Thank you for the condolences.

So I was looking around online for a 125mm bb yesterday and didn’t really find much in that length. Made me question my measuring. So I pulled everything out of the shell and had a closer look. It measures 124.5mm not counting the threads for the crank nuts.

Something that I did not notice when I first built the bike nearly 3 years ago is that one side (the right side in the photo) is about 3mm longer than the left side. Unfortunately I don’t know for sure which way I had it installed, but I presume I had the short end on the drive side, the chain ring was very close to the stay (probably backwards??). Can anyone confirm which direction it should go? Will a symmetrical axle work for this application or should I find one like this?

Last edited by 1speed4me; 12-22-18 at 06:49 PM. Reason: Wrong measurement
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Old 12-22-18, 10:46 AM
  #45  
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Something that I did not notice when I first built the bike nearly 3 years ago is that one side (the right side in the photo) is about 3mm longer than the left side. Unfortunately I donít know for sure which way I had it installed, but I presume I had the short end on the drive side, the chain ring was very close to the stay (probably backwards??). Can anyone confirm which direction it should go? Will a symmetrical axle work for this application or should I find one like this?
traditionally, with an asymmetrical bb, the longer side is the drive side. These are most common on road cranks, to give extra clearence for the chainrings. They are also found on older proper track cranks as well though, depending on the design. Ideally all square taper cranks should be asymetrical. There should be no issue in flipping it around, to get the chainline more narrow. (A common trick with conversions on older frames.) the problem with doing that though, is it will cause your non drive side crank arm to be offset way out. This probably wonít affect your pedal stroke noticbly, but if youíre concerned with aesthetics, it can look pretty odd. Most modern square taper bbís today only come symmetrical, obviously because different cranks require different offsets. If youíre going to switch from asymetrical to symmetrical, you have to take the offset into account, in your total length when converting, if you want the driveside crankarm to sit in the same place (chainline). The problem of course is that you can only take one side into account. That means one side will either be inboard or outboard from what it was designed to be.

Last edited by seamuis; 12-22-18 at 11:26 AM.
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Old 12-22-18, 07:38 PM
  #46  
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That is helpful, thank you!
And yes, I am overly concerned about aesthetics.

I've researched the Super Mighty crankset and I'm 99% sure it is ISO taper, not JIS like I had with the Super Maxy cranks. Since you mentioned that most BB's today are symmetrical, it sounds like looking for an asymmetrical BB would be a waste of time(?). So, correct me if I'm wrong, but in that case I would just look for a spindle that is 3mm longer than the 124.5mm that I have now(?). However, it looks like nearly every spindle I can find is a good 10-15mm shorter than what I have... and my head is about to explode from all of these different specs. Fun!
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Old 12-22-18, 09:02 PM
  #47  
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Put the BB back in the frame and install the crankset. Measure the distance between the chainring and chainstay. Muliply that distance by 2 and subtract 8mm(4mm each side) then get a symmetrical BB that much shorter than the current BB. Or you could just find out the correct BB length for that praticular crankset and get that size.

Edit: measure the distance between crankarm where the pedal mounts and the chainstay,not the chainring.

Last edited by BoozyMcliverRot; 12-22-18 at 09:08 PM.
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Old 12-22-18, 11:43 PM
  #48  
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Originally Posted by BoozyMcliverRot View Post
Put the BB back in the frame and install the crankset. Measure the distance between the chainring and chainstay. Muliply that distance by 2 and subtract 8mm(4mm each side) then get a symmetrical BB that much shorter than the current BB. Or you could just find out the correct BB length for that praticular crankset and get that size.

Edit: measure the distance between crankarm where the pedal mounts and the chainstay,not the chainring.

I can't mock it up. The BB is JIS, the Super Mighty cranks are ISO. If I tried to bolt it up it would ruin the crank (and supposedly stick out 4.5mm from where the last crank sat). I did try, I gave the nut a few turns and it didn't feel right so I stopped.

Edit: I suppose I could put the old Super Maxy back in, but would that directly relate to the Super Mighty?

I believe I now know what I need; 68mm shell, 125mm+ spindle, English thread, ISO taper. I'm out of my wheelhouse here, but I've searched pretty well and can't find anything worth using with those specs.
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Old 12-23-18, 04:40 AM
  #49  
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Originally Posted by 1speed4me View Post
I can't mock it up. The BB is JIS, the Super Mighty cranks are ISO. If I tried to bolt it up it would ruin the crank (and supposedly stick out 4.5mm from where the last crank sat). I did try, I gave the nut a few turns and it didn't feel right so I stopped.

Edit: I suppose I could put the old Super Maxy back in, but would that directly relate to the Super Mighty?

I believe I now know what I need; 68mm shell, 125mm+ spindle, English thread, ISO taper. I'm out of my wheelhouse here, but I've searched pretty well and can't find anything worth using with those specs.
one of the main issues with using a vintage crank. This is why I chose the dura ace 7400, because the 7400 bbís are still plentiful. You are correct that this crank is ISO not JIS. Both the road double and the track single, are 144bcd. The track used a 109mm spindle and the road used a rather odd 113.5mm spindle. 125 seems way too long and is certainly not the original spindle length. Any 68mm asymmetrical ISO 109mm spindle should be perfect for setting it up as a single speed or fixed. For maintaining clearence for and inner chainring and an outer bash guard as you have yours setup, a 68mm asymmetrical 111 or 112mm ISO spindle should be what you want. I just have no idea how a 125mm spindle came to be used. My DA 7400 crank uses the original asymmetrical 112mm spindle. Setup as a singlespeed I have a chainline at the outer position of 46mm and 41 at the inner chainring position. With a 111 or 112 mm spindle you should end up with similar at the outer and inner positions.

most 70s and 80s higher end square taper cranksets used similar spindle lengths. Typically 109mm for a track and 112-113 for a road double. Only use I could see for 125 would be for a touring triple setup.
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Old 12-23-18, 09:05 AM
  #50  
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Originally Posted by 1speed4me View Post
I can't mock it up. The BB is JIS, the Super Mighty cranks are ISO. If I tried to bolt it up it would ruin the crank (and supposedly stick out 4.5mm from where the last crank sat). I did try, I gave the nut a few turns and it didn't feel right so I stopped.

Edit: I suppose I could put the old Super Maxy back in, but would that directly relate to the Super Mighty?

I believe I now know what I need; 68mm shell, 125mm+ spindle, English thread, ISO taper. I'm out of my wheelhouse here, but I've searched pretty well and can't find anything worth using with those specs.
Ah,I see. Good luck in the search.
BoozyMcliverRot is offline  

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