PeteHski

I wouldn't blame them. Front shifting is an agricultural concept. The modern mtb world isn't missing front mechs and triples. I think we are nearly there with road 1x13

eduskator

Funny I read this, because I just got my N+1 two weeks ago which is equipped with SRAM Force (first time SRAM user) and I've had nothing but issues with my FD so far. It seems like the FD needs to be PERFECTLY aligned and adjusted to work flawlessly, which is a PITA.

At first, the chain was dropping between the frame and the small ring when shifting from the big to the small ring. I adjusted the low limit screw to the tightest I could even though it was within SRAM's specs. It stopped. Last week, my chain dropped again but between the big ring and the crank arm when going from the small to the big ring. I adjusted the high limit screw to the tightest possible (it was also within SRAM's specs). It dropped again during the next ride. I then lowered the derailleur height and rotational angle (both were also within SRAM's specs). It worked. No issues since, but I am skeptical.

I've had 6 bikes equipped with Shimano (1x Tiagra, 2x GRX, 1x 105 and 2x Ultegra DI2) so far and I have never never had a single chain drop from any of them.

Finally, Force AXS shifts are slow as hell as compared to Ultegra DI2. I was told it's the same thing for Red.

PeteHski

I just made sure mine was set up exactly as recommended by SRAM before the first ride and never had any issues. Haven't had to adjust it since either. Did you pay attention to fitting the correct mounting wedge to prevent any flex, as I think that may be quite important here? Mine came with an assortment of wedges with different thickness, although the factory fitted one was fine on my Canyon.

eduskator

LBS took care of assembling it (I checked the whole bike at home right after picking up like I usually do with all of my N+1 and both the FD and RD were adjusted as per specs.). I was not provided with any extra wedge in the bag of parts they gave me, but I would hope that world's biggest bike manufacturer makes sure their bikes are equipped with the proper parts. If not, I would be disappointed lol.

Jrasero

I have had SRAM AXS FD on my last three bikes w/ zero issues. You do need to setup the front derailleur spot on with the included block and out I caution I do run a chain catcher, but frankly I had more issues with chain drops with Shimano 11 speed. I will say the FD does shift slower than Shimano Di2 but the new firmware has helped a bit, but SRAM AXS rear derailleurs shift faster than Shimano Di2

bampilot06

Only time my Sram Force etap has ever dropped the chain was a double shift. Big ring to little ring up front, and shifting the RD at the same time. Chain fell inside the little ring. 6700 miles on that groupset. 1 time isn’t bad.

PeteHski

It’s actually small details like that which sometimes get missed. Have you checked that there is actually a wedge fitted on the front mech mount? It would be an easy item to skip during a build.

jaxgtr

I have 2 bike running eTap AXS (D1 group) and have not had any issues with chain drop over about 4K miles. 1 was already setup, 1 bike was a conversion to it and I did the setup. It could not have been easier, and I did have to make sure to use the correct sized FD wedge. The FD's have just worked flawlessly.

eduskator

There is one installed (thin).

DaveSSS 

It's easy to make one simple mistake that results in chain drops. The most likely is the FD rotating out of alignment when the clamp bolt is fully tightened. All three of my bikes with axs do this, so I deliberately set the marks crooked in the opposite direction and watch that the marks are parallel to the big ring, after tightening. I never use a wedge. There is some suspicion that sram cranks have poor shifting ramps. I have used a Campy 48/32 and grx cranks with no issues.

I also think that some folks don't understand what parallel means and they may try to place the marks directly over the big ring teeth, which may not be parallel to the chain ring. Side to side position is what limit screws are for.

eduskator

Good point. Parallel on my Force AXS FD is both lines roughly 0.5mm off the centre of the teeth towards the small ring.

PeteHski

Ok, so you can rule that out as a potential issue. Just to clarify, yours is currently behaving itself since you checked the setup was perfect?

tomato coupe

I think you are the only person that has suggested that.

Jonob

[QUOTE=PeteHskiAre you shifting the front under heavy load? Is it dropping when shifting to big or small ring? I've been using Force AXS for 18 months now and it has dropped the chain 3 times when shifting to the big ring under very low load. It has never dropped a chain going to the small ring, which happens occasionally on my other bike with Shimano. At the moderate load I typically shift the front I can't see flex being an issue.[/QUOTE]

no not shifting under big load. FD set up by bike shop with the appropriate wedges. Drop happens randomly so I don’t see how it can be FD position. I thought rather to do with the chain ring especially since sram have binned the original force chain ring and now distribute force with a one piece chain ring like red. Not sure though happy for other advice. I think the current mechanic is very good they only do higher end race bikes I don’t think k the FD position is the issue. And if a bike shop that only does high end road bikes can’t set it up correctly then the product is not a good product. Happy to get the red front chain ring and report back
If people are interested

Jonob

[


i agree it needs to be set up absolutely perfectly but that is why I didn’t set it up myself

PeteHski

If you are not shifting under a high load then flex in the chainring is not likely to be an issue. I wouldn’t read too much into the chainring update. I think it’s just a normal product cycle update. Force was due a refresh and the move to a one-piece chainring could be for all sorts of unrelated reasons. But it would be interesting to see if a Red chainring actually fixes your issue.

When I was originally reading about these potential issues there appeared to be no real consensus about a cause and many riders have no issues at all. Fortunately I never had a problem myself so never looked any further.

Edit: Thinking about it more, if chainring flex was the issue then pretty much every user would be dropping chains regularly.

DaveSSS 

I suggest that SRAM shifting ramps may be lacking because I've done a dozen setups with 7 different Campy and grx cranks, on 6 frames, never used a wedge and never experienced chain drops or the setup sensitivity that others claim. It's easy to blame the FD, but most users have only owned one SRAM crank and automatically blame the FD. There's more to it, in my much larger experience.

I've never set up an AXS FD then found it to function poorly on the road and need readjustment.

PeteHski

But again if it was SRAM shift ramps, then why is it not affecting all users?

Maybe it’s just fussy about chain line, chain length, or even just user technique ie not as tolerant to variations in cadence, load etc. as Shimano. I would describe myself as a cautious shifter ie I never shift the front under load and I’m careful to pedal smoothly through the transition. I also never use rear shift compensation. The 3 isolated chain drops I’ve had with SRAM Force (from thousands of shifts) all happened on up shifts at very low load when I wasn’t paying much attention. They all popped the chain off on the outside of the big ring.

DaveSSS 

I'd say that some users get lucky and have a perfect setup. My setups don't have to be so perfect. A 1/8 turn of a limit screws doesn't create chain drops. I don't use a wedge either. Some would claim it's necessary.

Using sequential mode can certainly make chain drops more likely. Some users are also new to cycling and make poorly timed shifts. With sequential it will shift to the little ring and several sprockets smaller if you try to shift into the big/big. Then it won't allow any of the 5 smallest sprockets to be used with the little ring. I only set a 2 sprocket limit on multi-shifts to use for compensation if needed. I might use the big/big briefly.

I also use cranks that all have a 16-17 tooth difference that SRAM says won't work.

tomato coupe

My statement was that you’re the only one that has suggested the problem is due to the shift ramps on the crankset.

Polaris OBark

What is ambiguous is whether this is a dismissal or recognition of unique insight. (I read it as the latter, but others, like the author, might not have.) But I have always been a bit of an optimist.

tomato coupe

Neither, really. The statement “There is some suspicion that sram cranks have poor shifting ramps” implies that there is theory circulating that this is the cause of the problem. I’ve never heard anyone but the poster posit this theory. The merits of the theory were addressed by someone else.

DaveSSS 

It just seems obvious to me that there are either many incompetent mechanics or some other issue. I have been building up bikes for a long time, I'm a mechanical engineer and machinist by trade, so maybe this setup is easier for me. I've read dozens of threads on this subject. Many claim that only by leaving a slight chain rub in the big ring and 10T sprocket can they stop chain drops. I've never needed that. Anything in spec works for me.

I own two force and one rival FD for three bikes. The force models were manufactured over 3 years ago and the rival was new last year.

The idea of incompetent mechanics was thoroghly thrashed on another site, but there were posters who can't do their own work who claimed that every shop in town failed to fix their problem. You could postulate that there are many defective FDs out there or that the marks were incorrectly painted, out of alignment. There are many possibilities. All I know is I break a lot of SRAM setup rules and have no problems.

The current SRAM video seems very thorough. I can't use the plastic setup tool because it doesn't fit the wider teeth on my grx cranks. That's no problem.

tomato coupe

Your claim that most mechanics are incompetent is nonsense, and was rightfully trashed. And, since you've always worked on essentially the same frame geometry, your experience is actually rather limited.

Polaris OBark

Hence the "or".