Cross Chain
 

My Domane has an Ultegra Compact double on front and 10 speed on the back. I was wondering while I am in the little ring on the front how far I can expect to down in gears on the back before getting the chain crossed. I thought I should be able to go half way down but, when I do that my front derailer starts to make noise.

not sure, mine is an ultegra 6800 version but I get no real noise from cross chaining...I do not think mid-range should be an issue

in the smallest ring in the front, you should be able to use pretty much all of them but the last, if it's set up right. Are you using the trim position to move the front derailleur over when you get midway down the cassette. If you cant, all that it probably needs is a lower limit adjustment + some sufficient cable tension.

Yup -- if the chain is rubbing on the front derailleur cage, you have a derailleur lateral positioning / "trim" problem.

With a 2x10 I would expect every combination to work, except for large-large cross and possibly small-small cross.

If you can't go more than half-way across the cassette w/o it rubbing, it sounds like there's an adjustment issue. The last Shimano-equipped (10s) bike I had could use 8-9 of the cogs w/o rubbing.

Thanks for the input. For some reason, I thought I had the half step trim on the big ring only now I know it is on big and small ring.

Lol - I have been missing out on some gears I could have used a time or two

I think with modern compacts and derailleurs, you should be able to use virtually all the gear combinations. I seldom find myself using the small/small (34/12) combination, but commonly use the large/large (50/27) at least for brief periods - e.g., going up a significant but not outrageous hill in the big ring, and slowly moving up the cassette, if I find the 50/23, then 50/25 combinations too much, I'll just go for the 50/27 for a while. If it were a longer haul, I'd switch to the small ring.

Cross chaining, the biggest non-issue to seize up bikeforums. Cross-chain all you want/need, nobody has ever proved it has any bad effects. As for power loss, low angle offsets cost little, do the trigonometry if you don't understand....

I never give it any thought. If I can't shift, I know I'm in the wrong ring!

I think most of the "Cross-Chaining Is Bad!" aphorisms are holdovers from the days of 5- and 6-cog clusters; I agree that a modern (10- or 11-speed) drivetrain with compact 50/34 chainrings is pretty much immune from any possible equipment damage or performance degradations when cross-chained

...but that doesn't necessarily mean that "Cross-Chaining Is Good". The biggest problem I see with people who habitually cross-chain is that they essentially back themselves into a corner gear-wise: They run out of cogs before the terrain they're on runs out of challenges, and then they're forced to do an inopportune front shift, usually with disasterous results (huge change in cadence, or dropped chains). If they'd been more aware of what gear they were in and better anticipated how to maximize their efficiency on the terrain, they would've done some preemptive shifting earlier to prevent ever being in that dramatically cross-chained condition.

Most riders have indicators on their brake levers/shifters and always know what gear they're in. As stated above by others, the usual case to be cross-chained is in the big front ring because the ride is cresting a small hill/rise and needs it for a short burst. If someone is dropping a chain whilst shifting, the issue is mechanical and has nothing to do with poor bikesmanship.

I just laughed so hard I passed coffee through my nose!

Today's ultraflexible chains help alot, but cross chaining still does accelerate chainring wear. I run 2x6 with SRAM PC-58 chains on all of my road bikes, and I use 11 of the 12 gears -- everything but large-large, which tends to run noticeably roughly, even though my chains are not overly taut.

I hate it when that happens to me. :)

Agree -- I know what gear I am in solely from the positions of the shift levers, since my road bikes are all friction shift and I run my mountain bike in friction mode, which allowed me to upgrade from a 7-speed freewheel to an 8-speed cassette simply by swaping the rear wheel and tweaking the limit screws on the derailleur.

Same here, must be riding a hybrid with flat bars to have a gear indicator on a brake or shift lever. Didn't Shimano try, and fail, at having indicators on the Flight Deck stuff, a few years back? And, poor bike skills can certainly cause a dropped chain, pushing for another shift really hard can do the trick, on some brifter or double tap systems.

Bill

I wasn't drinking coffee, but I agree!

J.

With a double cross chaining should not be an issue. If the chain is rubbing the front derailleur and trimming does not fix it, there is an adjustment problem. I've used all the gears with no issues. Cross chaining was never an issue on any of my doubles regardless of the number of cogs. However, I've never ridden the newer 10 or 11 speed bikes.

I can adjust the triples on our touring bikes so there is no chain rub in any gear combination. However, cross chaining is not recommended even though it will not cause a problem if used only for a brief period.

I'd flip where I put the "possibly", as the large-large is less likely to be problematic than small-small.

I try to avoid cross-chaining but on my recumbents, it is so far from the chainrings to the cogs that the angles are much much less acute, compared to normal bikes. I occasionally find myself on the small/small or large/large combos with no evident problems.

Interesting use of "acute" here. I tend to think of an acute angle as anything between 0 and 90, so an angle either is or isn't acute. Like being pregnant, you can't have an angle that is more or less of it. OTOH, acute also means "severe", and in that case the word choice makes perfect sense.

Not criticizing your meaning or your writing - it is clear - just musing on the word.

It's a non issue . To quote Shakespeare - "Much ado about nothing!"

Yeah just listen to your gears. If you don't get noise from cross chaining, you're okay for short term use. Even some pros for it in midst of critical parts of races.

Cross chaining is absolutely common on all derailleur bicycles, simply because there can be only one proper chain line.

Cross chaining causes additional friction and, of course, wear. A bike that has been cross chained a lot, will show the wear on the alloy chain rings. The sides of the teeth will be dramatically worn. Look at the teeth on the big ring and compare to the middle ring. The middle ring still has lubricant sticking to the teeth, while the big ring shows clean/ground sides to the teeth. This is what cross chaining does to your machine...

http://www.mytenspeeds.com/My_TenSpe...illeur_F_1.jpg

The wear on the cogs will not be as noticeable, but will, none the less, be present. The wear on the chain will also be accelerated, causing the chain to appear to stretch more rapidly, causing tooth wear, once again, to rings and cogs alike.

So, cross chaining is not good, when seeking dependability and longevity from the bicycle and its drive componentry. Cross chaining is not good when the rider is seeking optimal performance.

Big issue or small, cross chaining is a foolish way to treat a bicycle's components, even if you can't hear all of the wear and power robbing that is taking place.

I actually put one of those mechanical gear indicators on my Trek with the Dura Ace 6800 groupo-(or whatever the last groupo was with the external cable routing groupo). Works really well. All my other stuff on my other bikes the housing is routed under under the handlebar tape under the bars. I find myself occasionally looking back at the cassette when training just to see what cog I'm in to see how well I'm climbing that day. I'm envisioning some sort of wireless device that would give you the same information that would display on a Garmin.........think there is enough of a market for it**********.........back to the workshop........

Based on your premise (assuming a compact crank), is it best to try and use the upper half (the smallest cogs) with large chain ring and the lower half (the largest cogs) with the small chain ring?