Most likely the shift ramps won't be sync'd for mix and match ring combos.
Starting to make sense to me the more I think about it. I'm just a little slow sometimes. Guessing it based on angles.rockyuphill said:Most likely the shift ramps won't be sync'd for mix and match ring combos.
Yeah - thinking you are saying the same thing that uzurpator said and I finally realized. SRAM could have created a better graphic to show that. I'm convinced now at least in principle. We'll see how it works on the trail.Musturd said:The gearing is so teeth align for quicker shifting
26 is 2 x 13, +13 = 39
28 is 2x 14, +14 = 42
By having rings with teeth of equal multiples it allows every other tooth to line up with one on the other ring.
Just had a SRAM XX clinic.
riding29 said:I'm still not understanding this though.
Tnanks for the responses but the conversation took a little detour with why would I want 30/39 but and that is not what I was asking. I don't want/need a 26 especially if I have a 36 in back. If I had a 30 on the back I could stay there longer without having to shift the front rings. I don't live in a place where I need a 26/36 combo to crawl up a 5 mile hill. And I don't need a 42 or 44 either as I don't commute on this bike. 30/39 is just my preference if I could have it.
So hoping someone can still help me with the original question of why does the shift performance degrade if I would change the 26 ring of a 26/39 combo to a 30 so I have a 30/39.
I had read the content on the SRAM site
but it doesn't point out the why.
Here's all it really says "With X-Glide, all four upshift locations are identical and can be picked up by any outer link. " and I'm not sure what that has to do with the size of the small chainring.
From what I can see the front ring has no ramps and is just vanilla. Maybe there is something on the thing??