Bicycle Mechanics - High maintenance bike?

It seems every few months I have to bring my bike back into the shop to fix the rear derailleur. It always starts to jump around in the back after a while. It's a triple so that might have something to do with it. I have to bring it in again, feels like I was just there....

It seems every few months I have to bring my bike back into the shop to fix the rear derailleur. It always starts to jump around in the back after a while. It's a triple so that might have something to do with it. I have to bring it in again, feels like I was just there....

You may want to ask the LBS what exactly they're doing, and what's causing it instead of asking us to guess a billion different answers which may or may not be correct. And which there is no way of verifying if it's correct.

You may want to ask the LBS what exactly they're doing, and what's causing it instead of asking us to guess a billion different answers which may or may not be correct. And which there is no way of verifying if it's correct.

I saw that link you posted in the other thread, maybe I'll have to learn how to do it myself.

http://www.parktool.com/repair/byregion.asp?catid=53

There is nothing inherently "high maintenence" about your Cannondale so either there is a mechanical defect somewhere in your drivetrain or your LBS sees you as a continuing source of income.

First step is to learn how to adjust the cable tension of the rear der. 99% of shifting problems are the result of cable tension. Adjustment only requires that you turn one adjuster on the der and takes just seconds, so learn how to adjust and you will avoid many problems.

...maybe I'll have to learn how to do it myself.

That helped me a lot with my bike problems, less trips to the LBS, less time wasted, less money spent, more riding.

Check this out, I found this extremely helpful:

http://bicycletutor.com/

Adam

Your triple front has nothing to do with your rear derailleur falling out of adjustment. I think it really sucks how BF has instituted this whole "triples are bad, mkay" mentality. I haven't experienced any more maintenance issues with triples compared to doubles compared to compact doubles.

As stated above, you really need to learn to turn the little adjusting barrels yourself.

If you haven't yet, get a good book on bicycling and bike maintenance. It wil give you the basics on how to keep things runnning smothly on your bike. Most maintenance items on bikes can be handled with the minimum of tools and time and learning how to service/adjust your bike yourself will definitely lessen the frustration of always having to depend on your LBS to keep it on the road and safe.

Chombi

Get the Park Blue Book.

Could be: r shifter, r cables/housing, r derailleur, chain, cassette, frame.

Derailleur, chain, and/or cassette could be worn, cables not sliding smoothly through housing, shifter issues. Check derailleur hanger alignment, frame alignment. If you're only getting it in the largest or smallest cog, could be the der stops need to be reset.

But yeah, ask the shop what's up.

Cable tension only needs adjustment in the first few weeks after a new cable is installed, to compensate for housing bedding in to the stops. Smoothe shifting then depends on keeping the system clean - cables and under the bottom bracket. Bent rear der hanger can cause persistent shifting problems, but this isnt something that happens gradually.

Rear derailleur adjustments should last longer than that.

Ask your shop to check the ends of all of the cable housings. I've encountered a couple of cases in which the cable housing end cap wasn't doing it's job and the cable housing was gradually shortening itself. When that happens, a derailleur adjustment will make the bike shift fine, for awhile, but it deteriorates rapidly. That sounds to me like the situation you described.

Or one tricky cause to your constant out of tune gears could be that your derailer chain wheel has collapsed. if theres a large amount of sideways give in it the centre support may have collapsed... this is not a common problem but can also go unnoticed...

Funny, OP has this problem. When i was breaking-in my DBR Podium 1 yesterday, I noticed the RD was skipping when getting up to the larger sprockets. 1 1/2 clockwise turn of the barrel adjuster later and it's all smooth. :thumb:

Or one tricky cause to your constant out of tune gears could be that your derailer chain wheel has collapsed. if theres a large amount of sideways give in it the centre support may have collapsed... this is not a common problem but can also go unnoticed...

??

Hey Operator i suppose it only really happens on the low end derailleur with the large chain wheels, ye know what i mean, have you ever seen it!..

Hey Operator i suppose it only really happens on the low end derailleur with the large chain wheels, ye know what i mean, have you ever seen it!..
The OP's bike is a Cannondale CAAD8. It seems safe to conclude it has components above the Wal-mart bike level.

Number one i would make sure they are not changing your cable every time you go in because that is for sure not the issue and cables will stretch over time during use. So if they are changing it out every time that may be the problem and by the time it stretches out you think it is not shifting right although the cable just needs to be tightened up a bit or just the barrel adjuster turned a quarter of a turn or so. number 2, make sure you are not laying the bike down on the drive side if you are. This can cause the shifting to go out if the derailleur is bumped. third. I am guessing your bike shop would check but have them double check the derailleur hanger, it could be very slightly bent. forth option is that some corrosion may have happened inside the cable housing that is causing the shifter cable to not slide correctly through the housing. Lube can fix it, but sometimes it only works temporarily and could cause it to have issues soon after.

Number one i would make sure they are not changing your cable every time you go in because that is for sure not the issue and cables will stretch over time during use. So if they are changing it out every time that may be the problem and by the time it stretches out you think it is not shifting right although the cable just needs to be tightened up a bit or just the barrel adjuster turned a quarter of a turn or so. number 2, make sure you are not laying the bike down on the drive side if you are. This can cause the shifting to go out if the derailleur is bumped. third. I am guessing your bike shop would check but have them double check the derailleur hanger, it could be very slightly bent. forth option is that some corrosion may have happened inside the cable housing that is causing the shifter cable to not slide correctly through the housing. Lube can fix it, but sometimes it only works temporarily and could cause it to have issues soon after.

No they just adjust it each time, and then it works flawlessly. I just adjusted it myself, it seems to be working good so we'll see.

Number one i would make sure they are not changing your cable every time you go in because that is for sure not the issue and cables will stretch over time during use.

Cables don't stretch. The inner liner of the housing wears and so do the components of the shifter and cable stops. But 1.1-1.2mm stainless steel cables are more than up to the task of pulling a derailler without stretching.

Cables don't stretch. The inner liner of the housing wears and so do the components of the shifter and cable stops. But 1.1-1.2mm stainless steel cables are more than up to the task of pulling a derailler without stretching.

They do, just not significantly enough to be of any importance. High quality derailleur cables are pre-stretched at the factory. Seating of ferrules, and cable and housing units into their respective places would totally mask any miniscule effect of actual cable stretch.

As you have pointed out.

Take it to another shop and explain to them the problem. I have seen this before and the cable wasn't clamped in the rear dérailleur properly, causing the cable to slip and subsequent poor shifting.

I think it is a loose fastener between the shifter and the seat

Take it to another shop
No, no, no.

Learn to understand this simple system for yourself. There really isn't much to it.

You shouldn't need to spend a cent when you have such quality gear, unless you've bent something or it's getting old.

Minimise friction in the cables, ensure the housings have no reason to be mushy (kinks or poorly cut ends) and are a good length (no unnecessary bends, but as large a radius as possible), and adjust.

You may want to ask the LBS what exactly they're doing, and what's causing it instead of asking us to guess a billion different answers which may or may not be correct. And which there is no way of verifying if it's correct.

end of thread

end of thread

Wait there's more!

So instead of bringing it to my local shop, I'd thought I'd take it upon myself to learn how to adjust the rd and fd, which I did successfully. The FD cables are less than a year old, and the bike and components are only a couple years old, so its not old parts.

None of the cables are unraveling and they're all clamped tightly.

learn how to fix the problem. this will teach you what is causing the problem. no more problem.

Wait there's more!

So instead of bringing it to my local shop, I'd thought I'd take it upon myself to learn how to adjust the rd and fd, which I did successfully. The FD cables are less than a year old, and the bike and components are only a couple years old, so its not old parts.

None of the cables are unraveling and they're all clamped tightly.

So, what? Did you fix the problem?

Unravelling cables don't matter, cause it happens between the end of the cable and the pinch bolt. It's just ugly and prevents you from re-assembling the cable without fixing it.

If the problem persists, it's most likely due to too much friction, or mush.

Possible causes: kinks in the cable or housing, poorly cut housing, wrong length of the housing causing too much bend, crud inside the housing.

Make sure the housings are the right length to minimise bends, their ends are ground flat, use the tube on a WD40 can to squirt them clean, and that your cable is straight where it should be and has the right amount of bend under the BB to minimise springiness. If you've cut the housing between the shifter and downtube shorter or used a longer bit, that last point will need attention.

Your triple front has nothing to do with your rear derailleur falling out of adjustment. I think it really sucks how BF has instituted this whole "triples are bad, mkay" mentality. I haven't experienced any more maintenance issues with triples compared to doubles compared to compact doubles.

As stated above, you really need to learn to turn the little adjusting barrels yourself.

Maintence isn't the issue. Triples just don't shift as smoothly or quickly as do doubles. If I needed lower gearing, I would get a compact. With today's 10 or 11 gear set-ups, a double (with perhaps compact) is all that's needed. Shifting bewteen three front rings just doesn't work well.

Maintence isn't the issue. Triples just don't shift as smoothly or quickly as do doubles. If I needed lower gearing, I would get a compact. With today's 10 or 11 gear set-ups, a double (with perhaps compact) is all that's needed. Shifting bewteen three front rings just doesn't work well.

I see no logic in thinking the number of chainrings has anything to do with REAR der performance. My experience confirms that. In fact, of the various configurations that I own, the FRONT DER shifting performance is best with a straight double or triple. Compact doubles are not bad, but definitly not as smooth, especially going from the smaller to larger chainring. I presume that this has to do with the bigger jump in gearing than in either the straight double or triple.

Perhaps your experience with triples was with a poorly adjusted bike because my actual experience contradicts your opinion and seems logical as well.

Wait there's more!

So instead of bringing it to my local shop, I'd thought I'd take it upon myself to learn how to adjust the rd and fd, which I did successfully. The FD cables are less than a year old, and the bike and components are only a couple years old, so its not old parts.

None of the cables are unraveling and they're all clamped tightly.

Show old is the rear derailleur cable and housing? If you ride in poor conditions regularly, a "couple of years" will be about the useful life of the cable and housing, especially the loop from the chainstay to the RD.

Maintence isn't the issue. Triples just don't shift as smoothly or quickly as do doubles. If I needed lower gearing, I would get a compact. With today's 10 or 11 gear set-ups, a double (with perhaps compact) is all that's needed. Shifting bewteen three front rings just doesn't work well.

Show me an off-the-shelf compact setup that can go as low as a triple. Don't cheat by using different cassettes with each crank.

I see no logic in thinking the number of chainrings has anything to do with REAR der performance. My experience confirms that. In fact, of the various configurations that I own, the FRONT DER shifting performance is best with a straight double or triple. Compact doubles are not bad, but definitly not as smooth, especially going from the smaller to larger chainring. I presume that this has to do with the bigger jump in gearing than in either the straight double or triple.

Perhaps your experience with triples was with a poorly adjusted bike because my actual experience contradicts your opinion and seems logical as well.

Right. Triples don't affect the performance of rear der. But cross-chaining is an issue with triples and is virtually non-existant with todays doubles.

Right. Triples don't affect the performance of rear der. But cross-chaining is an issue with triples and is virtually non-existant with todays doubles.

Cross-chaining is a user issue, not a crankset issue. Due to the lack of overlap, compact doubles seem to invite users to cross-chain much more than they otherwise would with more standard chainrings.