I just purchased a new tri bike with Tiagra front derailer and 105 rear derailer. Sometimes when I’m going uphill the bike will shift without me doing anything, it seems to me more likely when I am trying to give a lot of power. Also sometimes when I try and shift it takes it a few seconds and is not very smooth and makes some noise. Would upgrading components fix this, are these just low quality? I’m new to the biking scene so don’t know much about anything.
Everyone will offer a piece of advice here, but having ridden everything from Campy to Shim to SRAM and even Sachs in the old days of covered wagons and shit here is my take.
Ride it til it breaks to get your moneys worth OR start now with SRAM Rival. There isn’t one bit of difference for the money from Rival to Red. Now with Shimano there is a HUGE difference between 105 and DA. You get what you pay for with them, but in my humble opinion SRAM just kicks the living shit out Shimano right now…especially if you are on a road bike and using brifters…Double Tap is on par with Ultra Shift for brifter comfort. And of course if money is no object drop some Record 11 on your bad self and never buy another gruppo as long as you live.
just needs a little adjusting.
105 is great stuff
tiagra is a bit ghetto but front derailleurs are real simple, should be no problem.
have a shop check out your parts, there are some minor ‘gotchas’ that can cause funky shifting. but it may just need a simple tension adjustment.
http://bicycletutor.com/adjust-rear-derailleur/
A poorly adjusted DA rear derailleur will shift just as crappily as a poorly adjusted tiagra RD, it’ll just weigh less. Changing the tension in your shifter cable by a half turn can make all the difference.
ditto, turn adjustment screw on rear derailer counter clockwise half turn, ride bike up hill hard, if still jumps turn another half turn until you get the right tention, this should fix your problem, not a more expensive derailer set!
Thanks for the help, I’ll give it a go.
+1 on the above.
Are your cables routed internally, or under the BB (as on ‘traditional’ road bikes)? Some people (I believe Sheldon Brown included) attribute the ‘phantom shift’ phenomenon to flex in the frame. If you have cables routed under the BB and you’re strong enough to flex the frame enough, it can actually pull your RD cable enough to cause a shift. This happens to me on my road bike periodically. Having shifts happen when you don’t ask for it during sprints or other high power applications is asking for trouble. Having the RD indexing properly adjusted will fix all but the most extreme incidences.
105 is great stuff
tiagra is a bit ghetto but front derailleurs are real simple, should be no problem.
Absolute.
105 is perfectly good quality. Moving up to ultegra or dura ace is more about saving weight than anything else.
It’s probably just an adjustment issue.
But also check your cables.
I have a 9 speed 105 Gruppo that has worn out two frames and is still going strong on my daughters bike.
If it’s the front that’s shifting it could be flex in the frame, I had an old Schwinn circuit that would auto shift into the little ring if I stood in the pedals to climb, if it’s the rear that’s shifting it probably needs adjusting. There’s tons of info on the internet on adjusting a derailleur. It’s not rocket science and everybody that rides should know how to do it.
Everything is fine.
It the new version of the Di2.
You just have to think about and…you’re in a different gear. Man, the Japanese are smart.
I rode for a long time (6 years) with 105/Tiagra. I am now riding with Campy Chorus (6 mos). In my opinion, it’s like the difference between a rental car, and a tight stick shift. I’m glad to have made the upgrade, and wish I had done it sooner. I find that Shimano DA is also amazingly crisp. I have used Rival & Force and found them very good as well. Exclude mechanical set up from these comparisons because in all cases the same person adjusted the parts - me. I am speaking specifically about crispness of shifting here. There is no doubt that all modern bicycle drivetrains will get you from point A to point B with no problem, just as a rental Punto (no offense) will get you where you are going.
Re: OPs problem though - yes, it is likely caused by poorly adjusted drivetrain.
I agree with the advice above to check the cable tension.
If this does not work take it to a shop and ask them to check if your RD hanger is straight. It is a simple check and fix. The RD is just hanging out there, it is easy to bump and bend the hanger, or sometimes it takes a hit during packaging in the factory or in shipping. If the shop that built the bike did not check it there is a chance it is out of alignment.
just needs a little adjusting.
105 is great stuff
tiagra is a bit ghetto but front derailleurs are real simple, should be no problem.
have a shop check out your parts, there are some minor ‘gotchas’ that can cause funky shifting. but it may just need a simple tension adjustment.
This was exactly it for me. My roadie uses Tiagra components, and I had the same mystery shifting problems. Every time I tried to lay into a hill, it would shift on me. Took it to LBS, thinking my RD was busted, he gave the tension a quick adjustment, and no problems since.
“tiagra is a bit ghetto”
in the same sense that a wheelcover is “ghetto”. But, neither one is going to cost you any appreciable time during a triathlon compared to the options which cost many times as much.