musicman716

Ok so I just finished building up my first track bike and I think my chain line might be off, but I'm not sure. It's a pake frame, with a shimano BB, Sugino crank, Formula track hub, and a dura-ace 16t cog and lockring. I need to measure again to be sure, but it seems like it may be off 5mm or so, and the 1/8" chain is making some noise. It could be just because the chain is new but what do you guys think? And consequently if my chain line is off, how can I adjust it?

zelah

peek at it, does it look off?

MrCjolsen

Hang the bike by the front wheel. Take of the rear wheel. Put it back on but don't run the chain around the cog. let the chain hang loose from the chainring and see where it falls. It should line up with the cog.

sivat

What length bb and which sugino cranks?

musicman716

It's a 68mm BB shell, with sugino messenger 44t cranks. My LBS helped me pick out the frame, BB, Crank, and Cog. Also, i used a laser and found the offset to be approx 4.5 mm. Is this enough to worry about?

transplant

radarkansas

he means, what length BB Spindle, not the frame width.

LóFarkas

How doesn't one notice 4,5mm before riding it? I'd not be satisfied with anything above 1mm.

matt_savvy

beat up the guy at the shop

sivat

Just get a shorter bb. The sugino 75s need a 109mm spindle, and the RDs need a 103. I'm not sure which the messengers need.

Edit: The Messengers are an upgraded RD, so they need a 103 mm bb. Might as well get the Sugino Bottom Bracket.

Igneous Faction

I'm having the same problem with my current build. I got an older, unused Dura-Ace BB that had a 103mm spindle and am trying to use it with the Sugino Messenger (RD's with an 1/8" specific chainring) and my chainline is also off by about 4.5mm.

At first I thought that the spindle length must have been wrong, but it's definitely a 103.

I don't know what to do.

Igneous Faction

"Yet another source claimed that the squares of Campa, Mavic and
Stronglight (ISO) are smaller than Shimano and Suntour (JIS) with the
result that JIS cranks will move about 4.5 mm further in.

This may conflict with the end of the square and result in a loose fit
or braking stress. for ISO cranks on JIS squares there's less contact
area between crank and spindle, since the crank does not slip perfectly
on the spindle. The result again is a higher risk of braking the crank.

But assuming those 4.5 mm and 2 deg, ISO is about 0.3 mm smaller than
JIS (2 * sin 2 * 4.5 = 0.3)?
ISO cranks (Campagnolo, Stronglight, others) won't go as far onto J.I.S. spindles as they ideally should.

J.I.S. cranks (most Japanese models) may bottom out if installed on ISO spindles."

(From Sheldon Brown's Site)

I think I may have just answered your question. JIS standardized parts (Shimano) have a bigger taper on their spindles. According to Toe-Clip, Sugino RD's are built to ISO size.

I am so sick of JIS vs. ISO. To solve the problem, both you and I will have to buy the matching Sugino BB.

Bummer.

baxtefer

suginos are JIS
*OLD* sugino's were ISO

sivat

Its really strange that a company like sugino would use ISO instead of JIS. If anything i would expect shimano to use ISO and sugino to use JIS. (BTW, i'm not disagreeing with you, just stating my confusion) On the plus side, the sugino bb is pretty cheap and looks pretty nice.

musicman716

thanks for the help everyone. I'm going to bring my BB and Crank back to my LBS and discuss the ISO vs. JIS issue, and probably return my BB and buy the segino BB. Hopefully they will allow me to return it since they are the ones who told me that crank and BB would work together....

musicman716

I think I figured it out! I double checked my spindle length and it turns out it was 107mm when it should have been 103mm. So I thought that was all, but then i realized if my spindle is 4mm shorter, that is actually only a difference of 2mm on each side, which would still leave me 2mm offset. Soooo I think that I may ALSO have a ISO vs. JIS issue, because it looks like the crank is not going far enough down on the spindle. I'm gonna go back to the LBS later this week and discuss both issues with them. Thanks again for all the help everyone!

musicman716

lol. its really convenient sometimes to have a father who has crazy obscure motorcyle and metalworking tools.

LóFarkas

Thing is, if you rode the crank on the wrong (JIS) spindle for a while, it may be a bad idea to put it on an ISO spindle now it has deformed inside... Ask Sheldon or God, whichever you got better connections to.

roadfix

neat idea, need to try that next time.

musicman716

I never really rode it, i just rode it in front of my house for 2 minutes, and not very hard at all.