Chain line issue

[fullerlee]

Hi all.
I'm building this old estay as a 1x9.

The front ring is currently on the front of the spider, but the chain line isn't right - it's twisting too much when on the large gear at the back.

But I can't get the front chain ring on the back of the spider, because it doesn't quite sit.

Not sure what my options are - spacers on the back of the spider?

Thanks!

 

[hamster]

It's difficult with those Hollowtech bottom brackets as there is no choice of lengths, unlike square taper.
I would probably file down the ring. Alternatively a new singlespeed ring from somebody like Superstar Components: https://www.superstarcomponents.com/en/raptor-chainring-104bcd-narrow-wide.htm
I like their rings, they are well made, run quietly and last well in my experience.

 

[Imlach]

Spacers between spider and chainring to get the ring into middle position where it ideally should be for a 1x9 conversion.

 

[Imlach]

Or convert to SS

 

[fullerlee]

Spacers between spider and chainring to get the ring into middle position where it ideally should be for a 1x9 conversion.

Are there spacers sold specifically for this task?

 

[Imlach]

Are there spacers sold specifically for this task?

Bolt washer can work but a thicker solid piece is preferred. Sram makes chainring bolt spacers. Should be easy to find.

Can find many on ebay, amazon

Here is some from sjs


https://www.sjscycles.co.uk/chainsets/12-wheels-manufacturing-chainring-spacer-each/?geoc=DK

 

[Imlach]

Can play around with different thicknesses until its smooth.

 

[Imlach]

Obviously you'll have to take into consideration needing longer chainring bolts etc.

 

[fullerlee]

Excellent, thanks @Imlach and @hamster

 

[Imlach]

Let me know how it goes