2x10 22/36 issue
dan1502
Posts: 568
I have been trying to set up my gears but am having problems which I can't seem to solve so some advice would be appreciated.
I picked up a bargain XX drivetrain last year, sold the crankset and bought some S2200 (Specialized X0 equivalent) cranks, then changed the spider and rings to the new X0 22/36 converstion.
I also bought an MRP 2X chain device but have tried so set things up with and without this in place.
My bike is a Santa Cruz Tallboy Carbon with 73mm BB shell (standard external). I'm using a GXP Ceramic BB that came with the XX groupset.
The front mech is the new X0 mech designed to work with 22/36 set ups.
Anyway the problem is no matter how many times I have tried to solve it, if I set the H limit so that I can shift to the big ring up front whilst in the lower gears at the back, when shifting to the big ring up front when in the high gears at the back it overshifts and drops the chain off the outside of the big ring.
To get the front mech aligned to close to the specified 1.5mm gap between it and the chainring edge means screwing the H limit pretty much all the way in. If I do this there is no way I can shift to the front big ring without being a long way up the gears at the back.
I'm guessing it's a chainline issue. I changed the mech hanger at the rear for a new spare I had in case it was that. The new one was slightly thicker than the old one, thereby moving the rear mech out a bit.
It will probably end up going back to the bike shop but as that's a fair distance away advice on what else I might try would be appreciated. Unfortunately I sold the set-up I took off so the bike is out of action. If I could get this working I think I will like it.
I picked up a bargain XX drivetrain last year, sold the crankset and bought some S2200 (Specialized X0 equivalent) cranks, then changed the spider and rings to the new X0 22/36 converstion.
I also bought an MRP 2X chain device but have tried so set things up with and without this in place.
My bike is a Santa Cruz Tallboy Carbon with 73mm BB shell (standard external). I'm using a GXP Ceramic BB that came with the XX groupset.
The front mech is the new X0 mech designed to work with 22/36 set ups.
Anyway the problem is no matter how many times I have tried to solve it, if I set the H limit so that I can shift to the big ring up front whilst in the lower gears at the back, when shifting to the big ring up front when in the high gears at the back it overshifts and drops the chain off the outside of the big ring.
To get the front mech aligned to close to the specified 1.5mm gap between it and the chainring edge means screwing the H limit pretty much all the way in. If I do this there is no way I can shift to the front big ring without being a long way up the gears at the back.
I'm guessing it's a chainline issue. I changed the mech hanger at the rear for a new spare I had in case it was that. The new one was slightly thicker than the old one, thereby moving the rear mech out a bit.
It will probably end up going back to the bike shop but as that's a fair distance away advice on what else I might try would be appreciated. Unfortunately I sold the set-up I took off so the bike is out of action. If I could get this working I think I will like it.
Santa Cruz Tallboy
0
Comments
-
How is the BB set up?
Rear mech hanger will change nothing except for your rear mech set up. No effect on the front at all.
Sounds like you still need to set the front mech correctly or BB is not set correctly."Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools :?:SheldonBrown0 -
BB is an External GXP with no spacers added. When the BB mounted chain device is on its thickness plus a 1 mm spacer as instructed in the guide will affect things though. The spider/ring set has a marking that I think means it is 49 mm chain line and my frame is supposed to be 50mm if that helps. I have the front mech set with about a mm gap between it and the large chainring and have tried my best to make sure it is parallel (and tried adjusting several times).Santa Cruz Tallboy0
-
Eh, you don't use the H-screw to adjust that gap AT ALL, it's the height of the mech......the gap is radial not along the axis, sounds like you have set it up all wrong.dan1502 wrote:
To get the front mech aligned to close to the specified 1.5mm gap between it and the chainring edge means screwing the H limit pretty much all the way in.Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.0 -
No, you've misunderstood me. You are referring to the height gap of 1-3 mm. I am referring to the gaps of 1.5mm suggested by SRAM when setting the H and L limits. Ordinarily I just set these to the maximum limit I can get away with without chain rub but SRAM do actually give a suggested gap in the instructions which is what I was referring to.Santa Cruz Tallboy0
-
OK, well consider it a guide only, don't stick to it if it prevents you getting it right....
Have you checked/tweaked the toe in/out of the front mech, tweaking it slightly toe out as that will shift it earlier in the lower (bigger) gears out the back while maintaining enough coverage to stop the chain going off the outside in the higher (smaller) gears.Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.0 -
Yes, I realise that is only a guide but was just mentioning it as it doesn't even get close.
I have tried adjusting the alignment of the front mech but not specifically as you say so will give that a try as I can see what you're getting at. It was similar thinking that made me think the rear alignment could have an effect on the front in that it might just bring the chain a fraction closer to the pick up point. That said, presumably I shouldn't have to adjust the toe and it should work if parallel so something might still be wrong. I'll give it a go though. Thanks.Santa Cruz Tallboy0
