eloy said:

Exactly zero. Just do it, you likely wont have a problem.

Do double check that the shifting works as expected, specially at the bigger side of the cassette and into your lower gear -- the lesser tension sometimes requires to re-adjust the b-screw to keep a tiny gap between the cassete and rear derailleur. 

@Eloy Strikes again- new chainring on, b limit screw adjusted, shifting is buttery smooth. cross courses await

So I have a SRAM eTap question. I was chatting with a fellow cyclist, and he mentioned that it should be possible to use the newer AXS shifters with the older (first gen?) 11spd 2x eTap derailleurs. Can anyone confirm this?

I am slowly replacing my broken Roubaix which is a rim brake frame and the new bike will most likely be disc brakes. I hate to have to get all new stuff, trying to re-use as much as I can.

I know of some mechanical disc brake options that will work with the 11spd eTap levers, but I'm also going internal bar/stem/headset cable routing and I hear with cable actuated stuff, the bends in the cable run can be problematic with such a run and thus hydraulic would be the better option.

I have no experience on this first hand.

Looks like the "newest" (D2) AXS shifters are not compatible with 11 speed derailleurs.

However, the previous (D1) AXS shifters are compatible with 11 speed derailleurs.

Here's a SRAM page about it:
https://support.sram.com/hc/en-us/articles/6029351443099-Do-SRAM-eTap-AXS-shifters-work-with-eTap-11-speed-front-and-rear-derailleurs 

And a handy chart with model numbers (note that the red boxes are compatible if using the right firmware):
https://www.sram.com/globalassets/document-hierarchy/compatibility-map/road/SRAM-RED-eTap-11-Speed-Component-Compatibility-Map.pdf

Interesting, I can find ED-RED-D1 on eBay with low use relatively cheap. I will go check my current DRs and ensure of the model number that way I can just get the shifters and the calipers / hoses, and move my existing crank DRs and Cassette over. That would save me quite a bit.

Well looking at eBay I can also get the SRAM eTap 11spd hydro shifters... 

Please report back on how it goes.

--- 

This is an interesting space, I always wondered what drives decisions around compatibility of electronic systems -- i.e. why do the latest DI2 or AXS systems support only 12 speed cassettes.

Customer support is one consideration, the more open a system, the harder it is to pinpoint an issue, stay on a happy path, and more edge cases appear.

But otherwise business and marketing appear to be driving forces here, and not product and tech. That is, it is a business/marketing choice not to make these more backwards compatible and future proof. 

In your example, the shifter just tells the derailleur move one that way or this way, as long as they both use the same protocol and understand the high and low limits, why would it matter if it is 10 or 8 or 15 cogs? 

This gap is explored by a Chinese company, Wheeltop, who is making a electronic shifter derailleur system that can work with 3 to 13 speeds cassettes

If I recall, the lack of backward compatibility between Etap (gen 1) and Etap AXS (Gen 2 and beyond) was a change in the wireless protocol they used (possibly for security/reliability reasons, but my memory is fuzzy on that point).

You are definitely on to something, even LTWOO is making multi speed compatible electronic shifting, again another Chinese manufacturer.

But we are seeing this with everything, cars, electronics, computers, phones, appliances, etc... Yes there are some innovations which push for new, but in the end, I do believe there is a lot of planned obsolesce.

If you don't buy new stuff the company can't increase its profits. These days it's not about profits per se, more often than not, the board of directors are not happy unless it's constant increasing profits. Which is not sustainable because at some point you reach market saturation.

Ran across some pretty interesting science today with regard to torquing and torque wrenches while doing some aviation-related studying.

The interesting part for bikes is that static friction is higher than dynamic, so you should always try and get the torque wrench to click in one smooth constant application of force, rather than in smaller "bites" of increasing pressure. 

Jules said:

Ran across some pretty interesting science today with regard to torquing and torque wrenches while doing some aviation-related studying.

The interesting part for bikes is that static friction is higher than dynamic, so you should always try and get the torque wrench to click in one smooth constant application of force, rather than in smaller "bites" of increasing pressure. 

does that mean different techniques or different tools?  

I coincidentally stumbled across a video from park tool about this the other day and they reiterated what Jules has above about a smooth motion. They suggest backing the bolt off a bit so you can get it moving and hit the expected torque in one motion rather than ratcheting up to it. They were using their standard tools so I'd say it's more of a technique than any fancy or special tool.

Technique not tool.

I get what they are saying but it becomes a bit of an issue  when tightening up things that need to be done alternately and a little at a time such as stem bolts to the steerer, crank arm bolts like in the Shimano cranks when they are opposite, etc... But even in those cases I suppose smooth is king...

I might hop over to Ride Brooklyn Sunday the 10th to see if they can order me some parts for my slow bike build to replace my dead Roubaix... Been searching online and can't find what I need on some specific items, and they are allegedly a distributor.... Hopefully by the new year I'll have this thing complete...

Light Bicycle rims were delivered this week and after inspection they seem very well made and finished even if not the most refined (my experience of carbon rims are pretty limited though). After a rough couple of work weeks I think I may just pay my local shop/master wheel builder to lace them up to the DA track hubs.

I’m building up a new Cannondale Supersix this winter and wanted to get some feedback on some choices I’m making. 

The build is easier with sram , i also like the companion app

Mark Taylor said:

The build is easier with sram , i also like the companion app

seconded this ^^. I like the SRAM batteries, they are easy to charge. I haven't used a Shimano Di2; I have had a great experience with my SRAM Force AXS. I would opt for the Quarq power meter if you can, it is fantastic. The micro adjust for the RD on SRAM is a bit finicky to get right. If you can, get an etap version so you can add blips to your bars. I can't on mine. Those are my only 2 complaints if I would even call them that... 

I have the Firecrest 303 wheels as well and I love them. 

I enjoy the eTap 11spd SRAM Red I have on my defunct Roubaix. Since the bike was external cable routing the wireless option was great and clean looking, no zip ties holding wires on the frame. I don't like the hood feel as much as the Shimano, but still better than the 10spd 105 hoods.  I will be moving the 11spd eTap over to the new bike I'm building. Need to rush and get all the materials before the new tariffs take place... I hear companies are already scrambling to fill inventory before it's too late.

BUMP

@DavidVibert I think it's personal preference. Both are great groupsets and each has slight edges over the other here and there but no real clear winner in my opinion.

With the newest generation of Di2 being semi wireless and getting rid of the junction boxes, set up is really simple and straight forward (though Sram's full wireless is obviously easier). The eTube app is rough around the edges (Sram is the clear winner there), but for the little bit you use it, it gets the job done.

Bleeding the brakes is the real difference to me. Because DOT fluid holds air in solution far more than mineral oil, bleeding Sram brakes isn't necessarily hard, but I find the process to be more difficult/PITA than Shimano.

Quarq powermeters are top notch, you can't go wrong there. Other companies like 4iiii also make a good single sided meter these days for relatively low prices. From what I've seen from GP Llama and other testers out there, the Shimano meters still leave a lot to be desired and seems like they haven't figured it out yet.

After checking out the bikes at Ride Brooklyn last night I'm going to put together a budget to work towards buying a new race bike this year. I'm unsure what bike, but I'm going to try to stick to cable/mechanical shifting. The compromise I need to make are on disc brakes which are basically unavoidable as I think that decision has been collectively made by the industry over rim brakes (RIP).

I'm researching, but would love to hear real world opinions from KCC friends on hydro brakes - gear, set up and maintenance, etc.. I'm fairly competent at servicing my own stuff so want to make sure I know what I'm getting in to. How often do you change fluids, cables, and do general cable related maintenance (not rotors or pads)? Are your service intervals a requisite or is that just to make sure things continue to work without issues?

@David Yang I am sorta in your boat on my slow my new bike build to replace my Roubaix. Also forced to go disc brakes and since I have components from my 11spd SRAM eTap, hydro it is.  As you saw last night I got my rotors. I have disc with my CX bike and I haven't seriously maintained that bike in a while since I have't been able to race CX.

There are many advantages to hydraulic disc brakes. Some quick notes in no order:

• The only thing I regularly need to replace/service are the pads (I have yet to ever replace a rotor, altho maybe soon)
• When it comes to the hydraulic brake cables, they are set and forget. Once set up, you never have to route a brake cable ever again -- Unless you tinker with your position, or need to cut or reroute the cable for some other reason, or I guess a crash could damage one..., otherwise there's no reason to change them at all.
• I have a little protective plasticy/rubber thing where the cable sometimes touches the stem
• Bleeding is relatively easy, but you need a space to do it (i.e. do not do it in your 1bed NYC apt) like a basement, backyard, or even front stoop
• I've had my crux since 2019, I have bled my rear brake 3 or 4 times, and my front maybe once, maybe never
• A small consideration is that shimano uses mineral oil, and sram uses dot fluid, neither is better or worse, but you can't mix bleed kits, once you used a kit for mineral fluid, it should be used for mineral fluid forever 
• Dot fluid can be corrosive, but designed to dissolve in water or alcohol, so if ever touches anything it shouldn't, just spray some water on it
  

Good luck! 

I guess not too different from bleeding brakes on car - more tedious than it is difficult. Makes me feel better about it, thanks.

Eloy pretty much covered it all. 

Having used the older version of Shimano hydro brakes (which are now the 105 12 speed brakes) and the current ultegra/dura ace (with the survo wave tech) you honestly can't tell much of a difference. Maybe when hard braking you have to use less force, but if you're braking that hard, the amount of modulation is the last thing on your mind. I'd save the few bucks and go for 105 brake calipers and upgrade to the dura ace rotors 

As far as Sram vs. Shimano, I personally like Shimano more. I think they're easier on the set up/maintenance front (not that Sram is bad, just less easy in my opinion) and the lever design is more comfortable.

But onto the most important question, what bike you leaning towards?!

They had an Ultegra TCR which was pretty great - came in under 17lbs without pedals, but it was a size medium so the bars, stem and cranks were all a size too large for me. Pete and Lynn were both all in on the Propel (that's what he rode this year to win in the park series and the NYS masters crit champs). I'm sold on the performance, but I just can't see myself riding on one.

I slept on it and looked at a bunch of options and am sort of settled on a Supersix Evo variant. Seems like a natural upgrade to the CAAD10. The newer entry/mid range models all have semi-hidden cables similar to the Giant models. The 105 mechanical Evo 4 model seems pretty great, though the wheels are very basic so would have to factor in another $1500-2k for race wheels which isn't insignificant you know?

The most interesting wildcard thought experiment is this Supersix Evo CX model that is my size and highly discounted and could theoretically be a "one bike to rule them all" situation. The BB drop is relatively low - just 0.5cm away from the road frame with a slightly more slack headtube angle and longer wheelbase. As a 1x I would have to get a separate 50T chainring for road use to get the low gear range of a traditonal 39x28.

https://www.ridebrooklynny.com/product/cannondale-supersix-evo-cx-396644-1.htm

awesome, one important caveat on cannondales is that some (or most) require the rear wheel to be dished differently than the rest of all bicycles… because 🤷🏻‍♂️

eloy said:

awesome, one important caveat on cannondales is that some (or most) require the rear wheel to be dished differently than the rest of all bicycles… because 🤷🏻‍♂️

Ah apparently they phased that out for road bikes recently but the cross bike still has it (and very likely the one linked above).