Should I be able to shift to large ring when on 3rd largest cog in cassette?
 

I have a 3 week old 2010 Madone 4.7 with 185 miles on it. It has SRAM Rival components. Recently I've started having problems shifting to the big ring. When I'm in the second or third largest ring on the cassette (climbing what passes for a hill around these parts) and in the small ring up front I can't shift to the large ring when I reach the crest. If I try to shift to the large ring the chain seems close to engaging and makes a lot of noise but it won't catch. I end up shifting back to the small ring and the noise stops since the front derailleur no longer is pushing the chain. Then after I shift the rear a click or two it'll shift to the big ring flawlessly.

So since I'm new to wrenching on things that aren't fixed by hitting them with a hammer or tightening to hundreds of foot pounds is there any advice you can give me on 1) how to fix this particular problem 2) give me some references - books, links, etc. - so I can learn more about the hows and whys of shifting/brakes/etc. in general and SRAM in particular.

Thanks

Www. Parktool. Com, look for dérailleur adjustment instructions.

Why u want to do that? don't u see the chain line gets all CROSSED? That u can do something doesnt mean it is the right thing to do, besides u can get the same gear using other combination.

Thanks, I checked out parktool - I guess if I follow the instructions hopefully I'll start to understand why I'm making them...unless it's just something that should be done and not understood. :)

I understand. I guess that since I'll be shifting quite a bit going downhill I want to get the biggest bang for the buck by shifting to the large ring first. Plus it's just fun to go "click" "click" "click" "click" on the rear while picking up speed without having to throw in the slower front shift. Maybe the right answer is for me to HTFU and carry more speed up the hill so I'm in the middle of the cassette and I can just shift to the large ring without a problem.

You most likely have a little cable streach on a new bike. You can adjust the cable tension to pull the der all the way over.

Brand new bike? I would be back to the shop pronto. That type of service is built into the price of a new bike.

Thanks. I'll try tightening the cable slightly (1/8 turn?) and see what that does.


Yep, brand new bike. Even though my LBS is happy to adjust it for me I really wanted to learn how to do it myself.

Lennard Zinn's Road bike Maintenance is a worth while Book. "Zinn and the Art of Road Bike Maintenance"

Howard Zinn's Peoples History of the United States Is good too ..
http://en.wikipedia.org/wiki/A_Peopl..._United_States

Unrelated, I think..

To answer your primary question, yes you should be able to shift to the largest chainring regardless of which cog you're in. As mentioned previously, it's bad to cross chain, say big cog to big chainring, but you should be able to if you so desire (free country, aitn't it?). It does sound like you need to tighten up your cable a bit. The aforementioned Park site is probably the best online (free) resource. Park sells a maintenance book, but I'd recommend a book by a different author, since you can get the info from their website and it's good to get another approach from a different author. I like to keep a book above my workbench, easier than running into the house with dirty hands and firing up the computer.

I have a 2008 Madone 4.7 and love it. It's my first real road bike, after 10 years of riding nothing but trails. I hate to say it but I've become a roadie.

I'm with Mudpie and believe that the bike should be able to shift into any possible gear combination. While riding crossed over is less than ideal, causing increased friction and wear, there are times where it can be handy such as to climb a short rise where you don't need or want to shift the front.

As others have noted it might be that you need more cable tension, but an easy test for this is to try to make the shift by pulling the bare wire away from the frame at the down tube. If it shifts better this way, add a bit of cable tension. If it shifts the same, your outer limit may be a hair tight, and should be backed off (slightly) to let the cage move over a hair more.

OK, so I ended up having to turn the barrel of the cable about 3/4 of a turn to tighten the cable and make the shift from small to large work perfectly - much more than it seems I should have had to. But the good news is it shifts from big to small and small to big. Then I shifted the rear into the small ring and all hell broke loose. The chain rubbed on the front derailleur on the small chain ring and came off the outside of the big ring when shifted to the big. Isn't adjust the derailleur fun? Oh well, loosen up the cable and try again.

First make sure both limits are correctly adjusted. Leave the lever alone for a moment, and shift the FD back and forth by pulling the bare wire away from the frame near the downtube. You want the limits set so the shifts occur cleanly, but no more out than that.

Once you have the inner and outer limits set correctly, then you can use the cable adjuster to fine tune the shifting within the allowed travel range.

Stupid question - I don't have a maintenance stand so should I improvise something with a broom handle under the bike seat with both sides of the broom handle held up with a ladder and shelves? Or should I invest in a real stand for the basic stuff I'll be doing? Or is there another way I'm not thinking of to pull the cable away from the downtube while turning the cranks with my other hand?

The broom on ladder thing should work fine, and more important shows that you have a creative mind, and don't insist on only made for the job stuff. Don't change your outlook.

BTW- if you're working in your basement and there are exposed pipes, make a quick workstand by tossing 2 ropes over a handy pipe and hanging the bike by the seat and handle bars.

You can also do whatever it takes (get married?) to get someone to hold the rear wheel off the floor for a few minutes while you work.

Hey, I used to race Formula 500s in SCCA autocross - my co-driver and I once spent a night putting a bigger motor in a car that hadn't been designed for it. We ended up putting the finishing touches on it in the morning by getting PVC and rubber hoses and pads to form intake runners and then zip-tie the carbs to the rear axle. Not recommended but it worked for the next day's event...creative is my middle name. :)

Alas, no basements here in north Texas. And while I have a wife she has learned that when I say "Hey honey, can you help for me a minute?" she should proceed with extreme caution. And if I didn't have a wife getting one would be the most expensive way to fix a shifting problem I could possibly think of. :D

Going to the big ring you should have highish rpm and very little pressure on the pedals. Not a good move as you crest a hill, especially if you are pedaling slowly. Better to shift the rear and do the front later. It's much easier for the chain to drop to a smaller cog than climb up to the big ring.

rival's one of those setups that can cross at least the big ring, and I've heard of folks who can cross chain small/small without rubbing as well. I can't on my 09 allez--i get rub on the smallest 3 rear cogs when on the 34t ring--but I can cross big/big no problem, all day long.

cross chaining isn't ideal, but something all you're looking for is a short period of ease

my setup: ultegra sl (6600 vintage) compact crank on rival front and rear derailleurs with a 11-28 cassette.

OP: the problem you're describing sounds an awful lot like the shop shortened your chain too much. I did everything by the book with my chain and have had no problems. small small has too much slack, but you can't actually USE it, so it doesn't matter. big/big has the RD's lower cog a tad forward, but it's nothing too crazy.

edit: 2many: rival shifts.. decently under moderate load. you're right in that it shifts a hell of a lot nicer if you're >60rpm though. otherwise it'll just jam up between the dr and the big ring

I went for years without a maintenance stand and finally bought one about 8 years ago. Now I cannot see life without one! Before I loan my stand to friends, I always say, "don't borrow this unless you're prepared to buy one". Once you use it, you'll probably want one. Based on your previous comments and spirit, it seems like you're mechanically inclined and wrenching is in your blood. Think of a stand as another tool.

The stand allows you to work on your bike without having to kneel or stoop down, plus you can pedal the bike and operate the shifting and brakes. This makes it easier to diagnose and fine tune. After every ride, I place my bike (road / mountain) and give everything a quick look over. Personally, if something is convenient, I am more likely to do it.

I have seen a lot of new riders try to shift while under full load as well. Don't do that. You have to ease off pedal pressure while shifting or it's not gonna be silent/smooth/easy, especially with more adjustment-tolerant components like SRAM.

In my opinion triple is useless, is not better just put compact in there? the shifting will get way nicer and the gear ration will be almost the same also, the problem with triple is that many gears ratios are constantly repeated, for example why use the 46x23 when probably u can get the same using (just making out the numbers ok? im not looking up the tables) maybe with a 32x17?

Many times is not a thing of how many gears do you have available but how wisely u can use what u have.

Happy it work out for the OP

Good luck :)

My standard for building and maintaining my bikes is that ALL combinations work. This is a perfectly obtainable goal. That's not to say I recommend using them all.

Don in Austin

This is one of the very few instances where you need to mess with the limit screws. Specifically, the outer limit screw (the inner one is fine). The outer limit screw is allowing the derailer to move too far outboard and derailing the chain to the next higher gear. Since you don't have a next higher gear, it's jumping off. Screw the tension screw in a little (a quarter turn should be too much).

The fact that it is rubbing on the small ring says to me that the cable is just a little tight. Back off on the tension of the cable a little too so that it will drop down onto the small ring properly.