Is Cross Chaining Actually Slowing You Down? | Gear Ratios That Cost You Watts On The Bike 

How about 1X vs 2X efficiency (assuming somehow equivalent gear ratios)? 2X would be a bit more efficient on the highest and lowest gears while 1X will lighter (200-300 grams on an MTB, less for a RoadBike), but will the weight saving be able to offset the loss of efficiency? Converted my 3X9 (11-34t cassette) MTB to a 1X9 (11-40t cassette), i can hear the cross-chain friction when i am on the lowest gear and the chain changes gear when backpedalled (main symptom of cross-chaining). I wonder if i would be better-off with a 11-34t 2X...

@@sepg5084 Go for shit and you’ll loose 3 times that.

During shorter climbs, I frequently shift to lower gears on the back while leaving the front alone until I'm cross-chaining. The only downside is that I can hear the chain rubbing but the bike still shifts and handles just fine. I don't know that I've ever taken it to the extremes shown in this video, but it just isn't a big deal to cross-chain when you need a quick minute at a lower gear.

Sometimes but the furthest I go on the cassette is the second cog from the biggest one. I believe Dura Ace has a function that stops it on the second to biggest and you carnt go to biggest cog but not tried it on Ultegra yet.

Depends. I tend more to do it in the biggy-bigs position, on light gradient climbs for short periods, but I try to stay away from the extremes by at least 2 cogs. The other way around, interestingly, I go to the big ring way earlier, in the middle of the cassette, it's just easier to pick up speed and cadence, for example when you're going downhill at the top of a climb and you can virtually throw any high gear in. I can recall a situation from yesterday's ride when I shifted back up a gear because it clearly made a difference in drivetrain noise. At the end of the day, I have a 105 groupset, chains and cassettes are actually quite cheap but I don't want to beat on my bike too much, even though a new chain every 5k wouldn't really hurt the wallet.

They're just being smart, sitting in and drafting.

@@mapk4655 no drafting is for vageeeeens

Lol 😅

... which is a proper strategy, as you really do not need these gears.But to be honest: When you are in a tough situation in a race or in the group, you may be forced to user these 'forbidden' gears. Imagine you are coming out of an ascent of 7% gradient and its constantly getting flatter and flatter. You are e.g. using 39/15, but in the process you will need ...14, ... 13 and even 12 or 11. If you do the 'double shift' (to, e.g. 52/16) you would loose contact to your group or even it would not work due to the high tension on the chain. Real life is not as easy as theory...

basically the message of the video is ride with Biggie Smalls and Sky's the limit then. Unbelievable i know.

I miss Piddly Widdly. :(

@@KeithHeinrich

I still run 3 by on my touring/gravel bike. So I prefer Middly Middly.

P Widdly, Piddy, or Widdy.. Also made the gravel classic: "Bump, Bump, Bump" and the adventure favorite "Been around the world"

That impression is entirely correct 😉

@@gcntech I feel like all the new cyclists must keep him busy.

He's the cross chaining police like Connor was looking out for supertuckers

"Beware people, beware!"

Then it cant necessarily be a problem if they make bike that purposely cross chains.

@@Snagmaster30lb Mtb powertrains differ from road powertrains. I dont know if its enough to counter the cross chaining, but there are many small differences.

@@marcalvarez4890 very small differences.

@@Snagmaster30lb True, but differences.

@@marcalvarez4890 ok, but lol

1x groupset have the chainring positioned in-between the big and small ring positions; thus, while your average cross chain angle may be greater, the maximum amount that you can cross chain is significantly reduced and this is where it really matters. 1x is actually really good for chain line as the increased variety of ring size means you can selected the perfect size for your riding such that you spend the majority of the time with a straight chain line.

I think it depends on the terrain. Where I live one would either ride up or down, at least it's what I like to do. If its mostly flat one would use the middle gears more often and 1x is more efficient.

1x is made to simplify mountain biking, front mech and additional front chainrings are inefficient in the trails

@@karlcorrz If your MTB does more miles on the back of a SUV than it does being pedalled and is only ridden in unsatisfying loops that go nowhere on purpose-designed MTB trails, then 1x is a fine solution. If your idea of a proper MTB spin involves biking in actual mountains, covering everything from fast road and fire road sections between trails to the steepest climbs you can find, with plenty of quality tech descending in between, on trails that were never intended for MTB's but accidentally are amazing to ride for anyone with the skill, all in one spin you'll need a bigger gear range. As for efficiency it's already been established here and in more scientifically rigorous tests that straight chains are more efficient. However, for the endurobro types MTB marketing is mostly aimed at, knowing how to use a front derailleur is getting looked at similarly to being able to drive a stick transmission car at this stage. With 1x the choice is between chewing the tiny top gear sprocket up in no time because anything over 25 km/h will already have you in top gear and spinning it out, or end up having a decent top gear and having to walk up climbs that could be pedalled easily with the right bottom gear. Keep in mind that unlike on road bikes, where 11 teeth is as small as top gear goes with decent chain wrap around that gear, modern MTB drivetrains have 10 tooth top gears, of which maybe 4 teeth end up carrying the entire chain tension due to them reducing chain wrap trying to increase shifting speed to compensate for the lower wheel rpm that ever bigger and therefore ever slower turning wheels are causing, so wear will be fast. Sadly buying a MTB that can even take a front derailleur is almost impossible at this stage, so after 25+ years mountain biking, I'm disgusted with the industry because even though Shimano make a proper 600+% range 2x12 drivetrain, I can no longer get bikes off the shelf with frames to which this drivetrain can be fitted. Shimano are a bit of a pain on this front too as XTR is the only option that allows people to get a 38 tooth big ring as part of a 38-28 chainset, which is closer to what I'm used to from 3x10 drivetrains with 27.5 or 26" wheels and this setup costs 3 times as much as 36-26 XT level chainrings, for literally no benefit bar saving a couple of grams. The idea behind this is not about me being anything like strong enough to push this top gear on everything, the idea is to make top gear high enough that I don't spend much time in it, to give it a chance to balance wear life of the tiny top gear sprocket against the lower gears that wear more slowly because of having more teeth to share the load.

@@nathanphillips875 except on my electric bike kit, where the front chainring is level with about the 6th cog. I know because bumps can pull the chain off in the lower gears.

Depends on what your big ring is.. :). 48 is the sweet one for general riding.

Mmm I heard that and laughed!!!

For a given power and final ratio, using a larger chainring results in _lower_ chain tension.

I remember one mountain stage where a (Schleck?) lost the stage because he cross-chained and then missed a shift, dropping the chain. It just shows that being a pro doesn't mean everything.

@@ericpmoss usually, it's shifting under load which causes the chain to drop or the fd not to function properly .. not cross chaining itself .. pro's cross chain on steep climbs precisely to avoid shifting rings while under load .. maybe, just maybe, frank shifted too late while under load causing his chain to drop ..

@@ericpmoss pro means everything.

My gravel bike came with a 46-36 chainset, and I've ended up quite liking it. The smaller gap makes it easy to avoid cross-chaining and the top speed is the same as a 50-12 (which I would only reach on downhills anyway).

105 is all you ever need in life #changemymind

@@mrendo4742 Agreed...why pay more???

Doesn't the chain rub on the front derailleur at some point? I am riding 105 and that's what's happening on my bike, possibly time to re-adjust it? I am new to this and particularly this group set.

@@Charles_Bro-son check for adjustment and use the trims built into the group set.

@@mrendo4742 agreed, I have Ultegra 6800 on one bike and 105 5800 on my other, both are brilliant, ultegra feels no different (brakes are disc in one and rim in the other so can compare those but the gearing is great) I only got the ultegra for one as it was a steal on eBay and comparable in cost to 105 so figured I may as well, but I would never buy a bike because of the “better” group set the costs simply don’t make sense unless you’re actually racing at a high level

But if it's 11 or 12 gears on the back, doesn't it have the same issue of the chain being at an angle to the optimal position?

@@harlanrosenthal8648 - you're probably correct, I don't usually ride much on the outer gears (inner or outer) so maybe that and the chainring being centered gives me the impression of efficiency. I do know that the drive train is quieter than my old mechanical 1x setup as well as my road 2x setup.

You'd think that an electronic shifting system would come with the ability to prevent cross-chaining through some setting. Or are they still not quite caught up with app technology?

With a 22spd bike you have a lower lowest gear and a higher highest gear. So a 22spd bike is better for climbing and going downhill on tarmac. I'd rather take a 2x groupset.

Same here

A friend and I were joined by another guy on a ride and he really struggled up the hills. In the end, we had to shorten the ride because he bonked big-time. As we ambled home, he was still staying on the big ring, even up the steeper climbs. When I finally suggested he dropped down to the small ring, he said will that make a difference?

@tim rawson You do realize friends tend to give each other hell on a friendly manner and laugh about it even if it is true, right? You sound like miserable company to be with...

@@sepg5084 everyone doesn’t do that though. It’s common some places and some places it’s really rude.

@@sepg5084 We both know that what you’re talking about, and what’s in the video, are two different things.

You had a black on black on blac Swatch? Sounds dope, now i want one. My sister loved Pop Swatch's when I was a kid.

You don’t have literally problem if your sprockets, chain, Rd can speak then they do have.

Not yet

Till that chain whips you in the back of the leg or just drops

Indeed....just get on yeah bike and ride.!

I do the exact same thing.

@@jefferywalker9809 I thought gears on the garmin was a gimmick at first but now I couldn’t go back! 👌🏻

What's the point of cross chaining if you can just shift to a better gear combo (unless there is no better option)?

@@sepg5084 it's because i can maintain my cadence that way

@@hucklejoko4838 I hope this isn't a stupid question, but: If you can achieve the same (or almost the same) gear ratio with a different combination, wouldn't you be at the same cadence? I know that on my 3x9 there is a wide range where I could achieve very close gear ratios on any front ring.

@@harlanrosenthal8648 i checked the math before deciding to stick with crosschaining, but long story short my Bigsy Big ratio is still slightly more than that of my 4th gear(which is the closest) when using the smaller chainring in the front. If i go any easier I'd be out spinning and therefore losing speed

50/30 is closer to 34/20, so 34/12 will definitely have you mashing your way up. Not only that, going from 50/30 to 34/12 requires shifting through the entire cassette. If you shift to the small chainring, you can just shift up 2 or 3 times on the cassette to get a similar gear ratio.

The two things are directly related. The most common model for quantifying wear in engineering is to consider it proportional to the energy dissipated by friction. And you minimize this dissipation when the efficiency is highest.

Thank you! I hate how Shimano made that decision for me! I

That was particularly savage 😂

😂

good stuff, thx for sharing

So if I have a 2x9, I can be in the big ring for gears 9,8,7,6,5,4, but should not move into 3,2,1?

...because it is a lie.

accuracy of powermeters are like 2% so @200W it is +/-4W for each powermeter. it will be difficult to compare the 2 results. You have to make more than 3 test/powermeter and /gear to have an average.

@@simonpeneau7802 1% if you have a decent power meter and trainer, but yes. Most of that will be calibration error rather than random error, so a comparison between various gears will eliminate the bulk of the meter inaccuracies. The rest you can deal with by taking a ton of readings - 10 second averages over a 20 min ride would be plenty to get the random errors down to the sub-watt level.