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The MuffinMan 01-11-21 10:52 PM

New Sram Force AXS Road 2x drivetrain - Please Offer Opinions What to Be Ready For
I'm almost finished with installment of the group set on my new road bike. Please tell me about your personal real world experiences with this drivetrain, positive, negative, and otherwise. I'm sitting down so have at it..... Thank you very much.

ls01 01-12-21 03:05 AM

Its heavy. Functions great, does exactly what it is supposed to do. I did have to use Red calipers to adapt to a post frame, they were a bit fussy at first.
I feel a little hoodwinked over the whole proprietary sizes and Dub nonsensn.leaves me feeling like I need a shower.before I ride.. The crank is a boat anchor.

Overall I'm ok with it

The MuffinMan 01-12-21 09:24 AM

Than you Is01 for the input. The Force disk brake rear caliper barely cleared the seat stay of the new Merida frame but it fits. I looked at what Sram requires to use their Dub cranks and BB. I do not like the idea of being confined to using only Sram product, plus I think their crank is ugly. So I stuck with 30mm BB spindle Wheels Manufacturing BB386 Evo Angular Contact threaded BB mated to 5 arm Rotor 3D alloy crank with Carbon-Ti Carboring AXS 50/37 chainrings. This is plenty of gear potential for me with the 10/28 Force cassette. Spins and shifts great on the bike stand. I've heard about frozen RD's so that's kind of what I'm expecting sooner or later. I'm not a weight freak so it's mute for me. How long you been riding it?

DaveSSS 01-12-21 11:52 AM

The crank only weighs a little over 700 grams, without a power meter. The word proprietary seems to be used often and incorrectly. There are many different crank designs and none are proprietary, just different. Some think that any crank without a 24mm shimano standard spindle is proprietary. Not

I have force axs on two bikes, but I want more range than sram offers. A 50/10 top gear is like a 55/11 and not what most riders need. I have used a Campy chorus 48/32 to get the same top gear as a 53/11, but I now use a shimano grx 46/30 crank with the chainline corrected with 2.5mm spacing washers. That crank is cheap, but heavy at 810 grams. I've never had a chain drop with either crank and I don't use a chain catcher.

I have set up the FD on four frames a total of six times and never had a problem. I don't use the wedge that sram suggests. I followed SRAM's video instructions. One thing to watch for is the FD moving out of parallel with the chainring when the mounting bolt is fully tightened. I only had about a 3mm clearance between the Campy crank arm and the screw at the tail end of the FD cage. After tightening, it touched the crankarm, so I had to loosen it and readjust. I had to use a flashlight to see the height window stamped in the cage.

I have also found that the new 10-36 cassette can be used with the standard RD, with a longer B screw. The wide RD does not have a longer cage or more wrap capacity. It has a longer main pivot mount to provide more clearance for the 36T sprocket.

The MuffinMan 01-12-21 03:52 PM

I see about 2mm clearance between outer cage and crankarm also. I will do just a little more tweak of FD as it's not quite parallel to outer chainring. I'm curious, would you mind sharing why you don't use the shim Sram recommends? Thanks for your input. I appreciate all the info I can get as I'm new to e world on bikes.

DaveSSS 01-12-21 04:00 PM

On my first installation, my frame had 406mm chainstays and the tire made it hard to install, so I decided to try it without first. No other brand requires a wedge. The mounting screws are tiny. I could see them failing quickly. Altogether, not worth the trouble.

The MuffinMan 01-12-21 04:12 PM

I guess it works for you. The Sram video made it sound pretty important to install. It wasn't hard to do. If it fails it fails.

DaveSSS 01-13-21 08:28 AM

Originally Posted by The MuffinMan (Post 21875042)
I guess it works for you. The Sram video made it sound pretty important to install. It wasn't hard to do. If it fails it fails.

You asked. I'm a machinist and mechanical engineer. I think for myself. Sram will also claim that the axs chain won't work with either of the cranks I've had success with and they'll not sell a crank with a 16T difference between the chainrings, that also works fine.

The MuffinMan 01-13-21 08:51 AM

So what is your take on why Sram recommends the wedge and the 13 tooth max differential for the FD?

DaveSSS 01-13-21 04:06 PM

The 13T difference is probably because sram can't seem to make decent shifting ramps for their chain rings. There are many complaints about chain drops in both directions, blamed on the FD, but both of my bikes with not-sram cranks work great. It makes no sense at all to design a 12 speed drivetrain to gain additional range, then take it away by not offering any cranks with a 16T difference. When I made the change to force axs, I was already using Campy 12 speed mechanical with a 48/32, but the new 10-36 cassette offered more range than the Campy 11-34.

I now have the same low gear as SRAM's wide 43/30 and more top gear with the 46 big ring. Makes sense to me. I've never read any sensible explanation for SRAM's chain ring limitation.

The MuffinMan 01-13-21 09:21 PM

Would a yaw chain catcher work on axs fd to prevent chain drop, at least on the inside?

DaveSSS 01-14-21 08:28 AM

Sram sells a chain catcher that will fit the axs FD. No clue if it works. I've tried k-edge chain catchers and found them to be worthless.

The MuffinMan 01-14-21 08:45 AM

Thanks for your input Davesss. Really appreciate it. :)

fattires 01-21-21 04:32 PM

I set mine up about month ago and have about 150 miles on it. The Sram videos were spot on except for the big ring to front derailleur gap. My group came with a front set up alignment/spacing tool that was not mentioned in the video. While the video says the space should be 1mm if I remember correctly, the set up tool makes that space about 3mm. This is on a clamp; not a braze on. So far shifting has been perfect.

I also installed the sram chain catcher based on the feedback from different forum conversations, but that may be based on the first generation stuff and I'm going to remove the catcher in the near future and see how it goes.

My only problem is I still have to adjust the calipers every other ride to avoid slight rubbing. Maybe it is a disc thing (my first disc bike), maybe my lack of mechanic skills, who knows. Nevertheless I would buy this groupset again without hesitation. At least until a Shimano wireless comes out.

The MuffinMan 01-21-21 09:19 PM

You mentioned the chain catcher and FD gap. I just put a Sram chain catcher on today, but I haven't had any chain drops on the inside after 4 rides. Just want it on for insurance. It mates to the braze-on bracket and AXS FD just fine. However, I did need to make the chain catcher hole a little wider in diameter as the AXS attachment screw was just a tad too wide for it. This was easily rectified by drilling it out to widen the hole. I have had several chain drops on the outside when shifting up to the big chainring. Today I adjusted the high limit screw a little more inboard and turned the FD so the cage would be as parallel to the big chain as possible. The FD is turned as far left as possible on the braze-on in order to achieve this. I also positioned it so that the cage bottom is only about 1mm above the big chain ring teeth. I hope these tweaks will eliminate or greatly diminish the frequency of outer chain drops I have had thus far. We shall se on the next ride.

About the front disk rub, I also hear it on my front caliper. I loosened the flat mount bracket attachment screws, jiggled it around to loosened it up, squeezed the front brake lever while gently retightening the screws, alternating between top and bottom screw until tight. Squeaking gone and no more rubbing. If it starts again, do this procedure again. You can also take the brake pads out and manually insert an open end wrench end between the pistons to push them back in to fully receded. Hope this helps and thanks for your input.

fattires 01-22-21 07:44 AM

Cool, yeah that sram FD tool aligned it perfectly, but the gap is the first thing I would change if I had drops. So far so good. I've even been trying the sequential shifting which seems to me swaps rings more than I normally would manually. Still super smooth shifting.

I think I'll try the business card trick on the hose side of the caliper next time I adjust them. Just so little space I may have to use a sheet of paper.

Anywho what bike are you dropping this group on?

The MuffinMan 01-22-21 08:02 AM

I have the Sram FD alignment tool too and tried it, but I did not like how much gap was showing between FD and big chainring. So I used the white lines on the FD and slid it down closer to chainring. I believe the smaller margin of gap the better to prevent chain from escaping off to the outside. If the 1mm gap doesn't improve the drops I'll go back to the 3mm gap and try that again. Trial and error.

What is the business card trick you speak of?

The drivetrain is on a new 2020 Merida Reacto 800E frame. I'm super happy with the fit and feel of this new machine. Got a good deal on fleabay from a guy in the UK. These bikes are not available retail in the states (yet).

fattires 01-22-21 09:56 AM

Since the piston seems to stay closer to the rotor on the hose side of the caliper after applying the brake and torquing the caliper down, adding a card between the pad and the rotor on that side before the centering process "should" offer some more clearance. Maybe it just reverses the bias and shifts the problem to the other side.
Just more stuff that I read somewhere. Easy enough to try.

Also in this same forum I recently read that there may be some variance in the way one tightens the through axle, so I'll probably try that first.

Nice frame by the way! That thing looks quick...

The MuffinMan 01-22-21 01:37 PM

I'm going to try that cc trick. Thanks! This new bike has taken riding to a new level with modern geometry, electronic shifting, and disk brakes. It's "crisp" and light! What are you on?

fattires 01-22-21 01:50 PM

Interesting because I went kind of opposite from you. A little more relaxed century easing geometry, custom steel forever bike. Like you though I have the same enthusiasm for mine. It's almost in it's final form--I went with some Hunt wheels just to get her rolling while I figure out long term hubs and rims. Those Hunts are working out fine for now though. One of these days I'll feel like stopping and taking a photo.

The MuffinMan 01-22-21 09:33 PM

There's a lot to be said for comfort, especially on a bike for several hours and miles. I'm always on top of seat, bar, and cleat position in order to alleviate lower back, butt, and foot pain. Once you find the sweet spot riding usually becomes quite pleasant (when not drilling it or in nasty weather conditions or surrounded by cars and buildings in some metropolis). I can totally relate to the long century ride bike style. Riding slow has to be one of the most relaxing activities of all. I still like the sporting side of cycling so I train for intensity and speed. I've always been that way. Something about riding to race keeps motivated. To each his own.

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