"When i look at pauls chart its recommending i need -3 or -6 offset to achieve a 49mm or 52mm chain line. Which in today's standards is very odd as most chainrings are 0, 3, 6mm. I am not even able to find any minus chainrings for purchase. Any suggestions on this? I attached a photo of Pauls chart, thank you!"
This is just a conceptual error. What Paul is calling a -3mm chain ring, that's exactly the same thing that other vendors call 3mm. All offset rings go inboard. My instinct (guess) from the chart would be to go for 49mm chain line, but if it were me I would measure exactly where the gap between cogs 6 and 7 is, and use that as my guide. If that measured number is about 49, then that's what I would shoot for. Then, when I did the build, I would take a close look at tire clearance in the lowest gear, and then decide if I want to go to 52mm chain line. Ideally, you'd have both 3mm and 6mm rings on hand and test fit both and then decide, but that's why doing a build in a shop is easier, because all the parts are there. Again, my gut is 49mm. I will offer a full refund of what you paid for my advice if I'm wrong. :) Bill Lindsay El Cerrito, CA On Saturday, October 11, 2025 at 6:13:36 AM UTC-7 Bryan H wrote: > Thank you everyone for suggestions! I have decided to go with shimano 1x12 > on my lugged susie. I am still figuring out chainline and which chain ring > to get. I posted in another thread but figured i would post it here as > well. I have purchased a white industries 73x113mm BB to pair them up with > paul 100% cranks. I am confused on which offset chainring i need to get the > correct chain line. When i look at pauls chart its recommending i need -3 > or -6 offset to achieve a 49mm or 52mm chain line. Which in todays > standards is very odd as most chainrings are 0, 3, 6mm. I am not even able > to find any minus chainrings for purchase. Any suggestions on this? I > attached a photo of Pauls chart, thank you! > > > > On Sunday, October 5, 2025 at 9:35:10 PM UTC-7 [email protected] wrote: > >> The GRX 822 showed up first and I installed it! I expected a 20g weight >> savings but it turned out to be more like 60g. The barrel adjuster is also >> quite nice, and the niggling clacking noise on my bike is now gone. (And to >> think I was suspecting that the frame was cracking when it was just a rear >> derailleur pulley going bad!) >> >> [image: PXL_20251005_223900079.MP.jpg] >> >> On Friday, October 3, 2025 at 9:03:23 AM UTC-7 Piaw Na wrote: >> >>> On Fri, Oct 3, 2025 at 8:56 AM Will Boericke <[email protected]> wrote: >>> >>>> Piaw, >>>> >>>> I’m happy you posted this! My 5100 on a commuter lives a hard life. I >>>> disassembled, cleaned and greased and still have squeaks. I’ll order new >>>> pulleys. Perhaps replacement sealed bearing units? >>>> >>> >>> I ordered both a replacement pulley set and found on eBay the Ultegra >>> level GRX822 rear derailleur which will work as a replacement for the >>> entire derailleur for $80 + tax + shipping. (A new m5100 is $28 or so on >>> eBay, but I figured I can afford to splurge on fancy parts on my most used >>> bike) We'll see which one gets to me first. >>> >> -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/rbw-owners-bunch/d14fc9b7-b532-43cb-b3b2-085fb6f7d22en%40googlegroups.com.
