heyjaffy

I built up my bfssfg iro with a formula rear hub, sugino rd cranks, sugino bb (103), and a surly cog, and my chainline sucks. My chainring is a couple mm outboard of the cog. I slapped a shimano freewheel on the flip side of the hub and with that the chainline is perfecto. Anyone running a formula with sugino/sugino with this problem? Is this just some wack spacing with the surly cog? My research had it looking like the formula would get along with the sugino/sugino combo like peas and carrots.

FERAL

Im running a Sugino Rd with a 48t and Sugino 68X103/ My rear is a Formula Fixed/fixed with a EAI 17t cog and no problems.
Anyone else?

orbThorn

Put the chainring on the inside position and it should be perfect. Well besides looks.

BuddyMike

flip your chainring around

skanking biker

i run the same setup on my pista with a dura ace cog---same problem--if I put the wheel inside the spider. my chainline is off a couple mm outboard to the rear. Ifv i put the spider on the outside, same problem but reversed

andre nickatina

My beater setup:
Sugino RD
Mystery loose-ball BB, JIS taper
Formula/EAI

The chainline was way off when I had the chainring on the outside of the crankarms... I decided instead of switching out spindles, I could flip the chainring... did it, everything looks perfect now.*

*** Disclaimer: have yet to read this bike, sitting in a shop right now. My chain may still explode in a climactic fashion.

In Absentia

That's weird. I prefer to ride my bikes.

andre nickatina

When there's no headset bearings in them?

I like to ride my bikes too, which is why I own 3. There's never any downtime when one is out of commission.

Igneous Faction

One possible problem... is your cog on backwards? I can't think of any other reason.

For anyone that ever has problems with RD's and doesn't have the Sugino BB, that's your problem.

666pack

my exact iro bfssfg setup: sugino rd cranks, sugino bb (103), formula hub (120mm), surly 17t cog, shimano 19t freewheel, wipperman chain (3/32).

my chainline is perfect. and i think yours really is too.

In Absentia

Take a closer look at my post. Particularly where your post says read and mine says ride.

SSSasky

My BFSSFG has formula hubs, and IRO track cranks with Shimano 110 BB. My chainline seems a touch off now, even though I don't remember it being off when these exact components were on my old frame...

onRoffR

I'm running the sugino RD2 48t ,Sugino BB 103, Formula hub 120 with a Soma 19t cog on my group frame and the chainline seems perfect. I have a white Industries ENO on the other side I've only flipped it once but the chainline seemed good on that as well.

vpiuva

I notice there are no actual measurements in this thread. What chainline(s) are you achieving at the chainring and at the rear cog? This may point you in the right direction for a solution.

FERAL

42

dijos

it's probably the cog. I have the same bb and cranks and hub and a soma cog. Duraace lockring, no problem.

queerpunk

you didn't do anything silly like thread the cog on shoulder-out, did you?

skanking biker

Sheldon brown's site has a list of the widths of various cogs and the resulting chainlines:



https://sheldonbrown.com/gloss_ca-m.html

not all cogs give the same chainline on a given hub

velomatt

Are you sure your cog/ring and chain are all the same size ? (3/32 vs. 1/8)

disconnec

Shouldn't matter, and if anything, would probably give more fudge-room in the chainline.. right?

Anyway, I'm running formulas, RDs w/ a zen messenger chainring, EAI cog, and a 103mm BB. It's all 1/8" and my chainline is perfect.

I saw someone with the chainring mounted on the wrong side of the cranks. Silly mistake, but, well, my guess is that you made a silly mistake somewhere... It should be fine.

heyjaffy

My surly cog is 17t also, but 1/8, not 3/32. I just switched the chainring last night from the 48t that came with the RD's to a 44t TA 1/8 ring. Chainline is still slightly off. If I move the chainring to the inside of the cranks (something that I couldn't do with the 48t, not enough clearance with the chainstays), then the chainline is a few mm off in the other direction.

The chainline is not dreadful, but I can clearly see the chain pulling out from the cog to meet the chainwheel, and it's a bit noisy (though I'm hoping that goes away some with a bit more riding, on that note, time to go spin)

Thanks all for your insight - I did go check to make sure I didn't thread my cog on with the shoulder out, I didn't, but I am that stupid to have made that mistake.

drewcifer

the surly cog is not as wide as other cogs. its almost a mm narrower than the eai

skanking biker

a clean chain is a quiet chain

heyjaffy

Problem solved. Took it out for it's first ride with it's new, more reasonable chainring for the hills around town...my smile was so loud that it drowned out any drivetrain noise (which seriously did dwindle) and caused a bit of selective amnesia as to a certain minor mis-alignment. Ride. Bike. Good.