Singlespeed & Fixed Gear - Did i screw myself ????

I'm building a old schwinn into a fixie. im using a wheelset off a redline 925 with the flip flop hub.

my concern is my lbs couldnt get me the bulletproof cranks so they talked me into the sugino RD, which they will order tomorow.

now that i started reading about the weird chainline they give im concerned! any idea what the chainline will measure for the rear with the 925 wheelset?
should i get the matching BB(103mm) for the RD, will any 103 BB work? do i really need a new BB.

should i tell them to cancel the order and go with the sugino messenger crank??

please help!!

Sorry I can't be a help for this matter, but I thought Messenger Crank is pretty much same set up as RDs as far as the chainline goes. Soma's description says 103 BB is recommended for Messengers as well.

http://store.somafab.com/surd2mecr.html

The Messenger and the RD2 are the same cranks
http://www.suginoltd.co.jp/singlespeeder_e.html

Just get the Matching 103 BB, and you will be fine for chainline. Don't listen to anyone else to who tells you otherwise

there are plenty of threads talking about the rd's chainline.

there are plenty of threads talking about the rd's chainline.

and what is the usual verdict?

i guess they are ordering the rd (not sure if there is a difference between the RD2 and RD), it was 60bucks for them or the messengers except the rd2 already came with a chainring so i figured might as well get more for my money.

so using the 103 bb everything should be smooth. how do i get the other mesurement they'll need for the BB?

so searching i found that the rd matched with the sugino 103 bb will give me a 42mm chain line how universal is that. and how will that compare to my 120mm rear wheelset??

42 is the track standard and the 120 spacing will have no bearing on the chainline, as the location of the hub would stay the same in relation to the crank whether it was spaced at 120,126 or 130.

120 mm over locknut dimension spaced track hubs are designed to give a 42mm chainline. The RD with a 103 bb will give 45mm chainline. just put the chainring on the inside of the spider gives a 42 mm chainline. Your problem is going to be that your schwinn will not be spaced 120 in the rear, maybe 126 or 130 or something else. so you'll play with spacers to get your chainline right. hope this helps.

so no matter what i need to order the 103 bottom bracket along with the rd cranks right?

and my lbs should be able to play with the rear spacers to give me the right chainline?

oh and isnt there a another measurement to the bb that my lbs will need to know to make the order? what is is and how do i measure it?

thanks

The other spec is the width of the bottom bracket shell on your frame. Yours is almost certainly 68mm, but you might as well measure it.

Also, even if the 103mm spindle doesn't work out right, your LBS should be able to supply you with the correct spindle (which will be ascertainable once the cranks are installed). This route is preferable to having to respace and redish the wheel.

I have a schwinn, RDs, formula hubs, soma cog and sugino 103; it all works together.

ok im gonna call the lbs to order the 103mm bb along with it.
when it all comes in i'll see if it works and go from there

Your problem is going to be that your schwinn will not be spaced 120 in the rear, maybe 126 or 130 or something else. so you'll play with spacers to get your chainline right. hope this helps.

Dropout spacing and chainline are mutually exclusive. Assuming it's a older iteration of schwinn with a 126mm spacing he should be able to just drop the wheel in and tighten things up. If the spacing is 130mm, he'll need to get a longer axle and either use larger (longer) or additional spacers/locknuts/widgets.

cold set the frame down and try your best to turn asymmetrical to symmetrical

Buy the Sugino BB. Don't have your LBS try and get some other spindle to match, they won't be able to. The only thing smaller is the Campy 102mm BB and that won't work.

In the end you'll have a 45mm chainline which might be perfect with your hub, cog, and lockring setup or might be a bit off, like it is with mine. Oh well.

thanks for the help so far.
today my lbs ordered the sugino rd's with the matching sugino bb, and a 42t chainring. cause the rd comes with a 48 and thats a bit much for me at the moment.

as far as the frame its a schwinn world. the wheel set fit nicely on there didnt feel like i had to tighten anything to make it fit. not ruse if the spacing is 120mm on the rear fork but im sure its close.

i guess as soon as the parts come in. i'll get to play around with them to get it close to perfect.

i know i want it perfect but how close do you acctually have to be on the front and rear chain line? will 3mm make a difference?

Yes it will. Your drivetrain will make more noise than it otherwise would. And it will be less efficient. Not noticeably though, I'd bet. Mine's off by ~2mm and I don't mind.

thanks for the help so far.
today my lbs ordered the sugino rd's with the matching sugino bb, and a 42t chainring. cause the rd comes with a 48 and thats a bit much for me at the moment.

as far as the frame its a schwinn world. the wheel set fit nicely on there didnt feel like i had to tighten anything to make it fit. not ruse if the spacing is 120mm on the rear fork but im sure its close.

i guess as soon as the parts come in. i'll get to play around with them to get it close to perfect.

i know i want it perfect but how close do you acctually have to be on the front and rear chain line? will 3mm make a difference?

I have the schwinn world, 103 bb, RDs, forumula hubs. I just have to use the inside position on the cranks.

http://www.fixedgeargallery.com/2007/july/3/AlexAThorn.htm

Don't listen to anyone else to who tells you otherwise
Yeah, especially not those with first hand experience.


I have a schwinn, RDs, formula hubs, soma cog and sugino 103; it all works together.

does it make noise when you ride?
my gf has rd + formula hubs, it's the noisiest of her two track bikes or either of mine.

significantly so.

Yes get the sugino BB. Aren't the rd's a 170 arm length? I rode on them and was not a fan. My roomie just snapped his Rd's at the bolts and just got the Pake cranks for 60 bucks they are 165's light and fairly stiff. same BB issue would pertain but I wouldn't ride the Rd's again. Don't get me wrong I love sugino just not the rd's. just my two cents, take it or leave it.
edit: you can get the RD's in 165's but I still am leary after a snapped crank and not impressed with their ride.

Yeah, especially not those with first hand experience.



does it make noise when you ride?
my gf has rd + formula hubs, it's the noisiest of her two track bikes or either of mine.

significantly so.


it makes some, but it really depends on the tightness of my chain; if it's really tight, I get a wierd little noise that feels like vibrating. if it's regularly slack, it's ok. I do kind of maniacally lube my chain, though.

to the OP:

there's got to be a better way to say that...