Go Back  Bike Forums > Bike Forums > Clydesdales/Athenas (200+ lb / 91+ kg)
Reload this Page >

Unwanted Shifting while climbing

Notices
Clydesdales/Athenas (200+ lb / 91+ kg) Looking to lose that spare tire? Ideal weight 200+? Frustrated being a large cyclist in a sport geared for the ultra-light? Learn about the bikes and parts that can take the abuse of a heavier cyclist, how to keep your body going while losing the weight, and get support from others who've been successful.

Unwanted Shifting while climbing

Old 10-14-11, 01:50 AM
  #1  
Senior Member
Thread Starter
 
mgw189's Avatar
 
Join Date: Aug 2011
Location: Binghamtony,NY
Posts: 171

Bikes: 2011 Trek 7.3 FX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Unwanted Shifting while climbing

Yesterday on my way home from a short ride I was climbing a fairly steep hill. It rises probably 40 feet over about 250 ft(16% grade? Is that possible?). I was standing while on the way up and had the bike shift out of gear. Thankfully I didnt fall (new clipless user) but it did startle me a bit. I did have to take the rear wheel off the other day since I had a flat is it possible that the derailer now needs to be adjusted because of that? I cant say for sure if it was the front or rear where the chain came off or skipped.

Edit its a Trek 7.3fx and only about 3 months old.

Last edited by mgw189; 10-14-11 at 02:05 AM.
mgw189 is offline  
Old 10-14-11, 02:05 AM
  #2  
[IMG]https://i4.photobucke
 
jeepseahawk's Avatar
 
Join Date: Apr 2011
Location: Inland Empire, CA
Posts: 754
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Watch this video, might help you..,,

https://www.youtube.com/watch?v=2j1gSwhsVN8
jeepseahawk is offline  
Old 10-14-11, 02:44 AM
  #3  
Senior Member
 
JimF22003's Avatar
 
Join Date: Apr 2007
Location: Northern VA
Posts: 2,654

Bikes: 2008 Trek Madone 5.5, 2009 Cervelo R3SL tdf edition, Cervelo R5 with Di2

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Shift, or just chain skip? Your chain and/or cassette might be worn.
JimF22003 is offline  
Old 10-14-11, 03:24 AM
  #4  
Senior Member
Thread Starter
 
mgw189's Avatar
 
Join Date: Aug 2011
Location: Binghamtony,NY
Posts: 171

Bikes: 2011 Trek 7.3 FX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by JimF22003
Shift, or just chain skip? Your chain and/or cassette might be worn.
Its possible that it was skip.... the bike is only 3 months old with a little more than 500 miles on it.
mgw189 is offline  
Old 10-14-11, 06:14 AM
  #5  
Senior Member
 
Join Date: Nov 2010
Posts: 1,365
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 286 Post(s)
Liked 125 Times in 58 Posts
mgw - if it's a shifting issue, it would probably be doing it when it's not under a lot of load (i.e. - normal riding, not just climbing). If your bike only has 500 miles, and it was new, go back to the shop and see what they have to say.
billyymc is offline  
Old 10-14-11, 06:51 AM
  #6  
Senior Member
 
Join Date: Jul 2010
Location: SE PA USA
Posts: 332
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked 3 Times in 2 Posts
Did the bike get its 100 mile derailleur adjustment? When I had my FX I had to take it back in for an adjustment at 100 miles since there is a lot of cable stretch right in the beginning.
knobd is offline  
Old 10-14-11, 06:54 AM
  #7  
Senior Member
 
tony_merlino's Avatar
 
Join Date: Oct 2011
Location: Northeastern NJ - NYC Metro Area
Posts: 795
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
OK, this is probably silly, but if this happened only after you removed and replaced the rear wheel, it's possible that the wheel isn't mounted correctly. If it's either loose or crooked, that might cause the chain to pop off the rear cassette under load.
tony_merlino is offline  
Old 10-14-11, 07:55 AM
  #8  
Senior Member
 
JonnyHK's Avatar
 
Join Date: Sep 2008
Location: London
Posts: 2,420

Bikes: Baum Romano, Brompton S2, Homemade Bamboo!

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 474 Post(s)
Liked 204 Times in 129 Posts
Cable tension to the RD?

New bike, stretched cable with use?
JonnyHK is offline  
Old 10-14-11, 08:02 AM
  #9  
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 27,485

Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones

Mentioned: 153 Post(s)
Tagged: 1 Thread(s)
Quoted: 6286 Post(s)
Liked 4,329 Times in 2,425 Posts
Originally Posted by mgw189
Yesterday on my way home from a short ride I was climbing a fairly steep hill. It rises probably 40 feet over about 250 ft(16% grade? Is that possible?). I was standing while on the way up and had the bike shift out of gear. Thankfully I didnt fall (new clipless user) but it did startle me a bit. I did have to take the rear wheel off the other day since I had a flat is it possible that the derailer now needs to be adjusted because of that? I cant say for sure if it was the front or rear where the chain came off or skipped.

Edit its a Trek 7.3fx and only about 3 months old.
It's a cable issue. That's why shops usually offer adjustments within the first year. Cables stretch...no matter what some people might say. It should take even a marginally knowledgeable mechanic 30 seconds to fix.
__________________
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!



cyccommute is offline  
Old 10-14-11, 08:57 AM
  #10  
Starting over
 
CraigB's Avatar
 
Join Date: Jun 2005
Location: Indianapolis
Posts: 4,077

Bikes: 1990 Trek 1500; 2006 Gary Fisher Marlin; 2011 Cannondale Synapse Alloy 105; 2012 Catrike Trail

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
There's a distinct and easily discernable difference between chain skip and an actual shift. Skipping will feel like a momentary elimination of any resistance. Your pedal stroke will lurch forward, and if it happens while standing, and you're not careful, you can have some problems staying upright. Inadvertent shifting, OTOH, will feel just like a real, intended shift - you will actually end up in a higher gear (I've never heard of an instance where an inadvertent shift went to a lower gear - it pretty much is against the laws of physics, at least at the rear derailleur), and it will be harder to pedal, and it will stay that way until you deliberately shift back down again. There's nothing inherently dangerous in it, you just might find yourself grinding to a halt.

The last time I experienced that "auto-shifting" was back in the days of friction shifters, on a bike that had a fair amount of lateral frame flex. I'd stand up to pedal up a hill, and it would occasionally shift on its own to the next higher gear. Inconvenient, as you might imagine.

Last edited by CraigB; 10-14-11 at 07:35 PM.
CraigB is offline  
Old 10-14-11, 09:33 AM
  #11  
Banned.
 
Mr. Beanz's Avatar
 
Join Date: Dec 2005
Location: Upland Ca
Posts: 19,895

Bikes: Lemond Chambery/Cannondale R-900/Trek 8000 MTB/Burley Duet tandem

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 4 Times in 3 Posts
A new bike with new cables will experience cable stretch. It might go out of adjustment once, it might go out 3 times within a couple of months break in period.

Although I have removed and replaced my rear wheels on several bikes and every so often when I replace the wheel, it seems to go out of adjustment. Some bikes are more sensitive than others. Some bikes I can remove over and over without a problem. Another I can be as careful as possible and it happens.

When removing and replacing the rear wheel, be sure to clean up the dropouts. They collect debris etc and if it's new, the paint may have chipped. Paint chips may alter the way it seats in the dropouts. ...But the fix is as easy as a 1/4 turn of the barrel on the rear derailleur.
Mr. Beanz is offline  
Old 10-14-11, 10:27 AM
  #12  
Senior Member
 
Seattle Forrest's Avatar
 
Join Date: Mar 2010
Location: Seattle, WA
Posts: 23,208
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 18883 Post(s)
Liked 10,646 Times in 6,054 Posts
Originally Posted by mgw189
Yesterday on my way home from a short ride I was climbing a fairly steep hill. It rises probably 40 feet over about 250 ft(16% grade? Is that possible?).
The steepest road in Seattle is a 21 % grade, so 16 % is entirely possible. ( FYI, the 20th steepest road here is an 18 % grade. )

If I were you, I'd take the bike into the shop and have the shifting adjusted. Especially since it's three months old - it's probably due for it anyway.
Seattle Forrest is offline  
Old 10-14-11, 10:29 AM
  #13  
Senior Member
 
rekmeyata's Avatar
 
Join Date: Sep 2010
Location: NE Indiana
Posts: 8,692

Bikes: 2020 Masi Giramondo 700c; 2013 Lynskey Peloton; 1992 Giant Rincon; 1989 Dawes needs parts; 1985 Trek 660; 1985 Fuji Club; 1984 Schwinn Voyager; 1984 Miyata 612; 1977 Raleigh Competition GS

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 1128 Post(s)
Liked 257 Times in 207 Posts
If it's a lower end bike then the frame flex may be an issue. But more then likely as Cycocommute said it's just the cable being new has stretched a bit from breaking in thus it's time to go in and get it adjusted for free at the bike shop.
rekmeyata is offline  
Old 10-14-11, 11:58 AM
  #14  
Senior Member
Thread Starter
 
mgw189's Avatar
 
Join Date: Aug 2011
Location: Binghamtony,NY
Posts: 171

Bikes: 2011 Trek 7.3 FX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks for all the input guys I appreciate it. Its hard to tell what it actually was... I am riding to work tonight so will see if it does it again. I have a small climb right before getting to work nothing as steep thankfully.
mgw189 is offline  
Old 10-14-11, 04:08 PM
  #15  
Senior Member
Thread Starter
 
mgw189's Avatar
 
Join Date: Aug 2011
Location: Binghamtony,NY
Posts: 171

Bikes: 2011 Trek 7.3 FX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Ok so on the way in to work it did it again and its more a skip than it is a change of gears and I think its coming from the crank.
mgw189 is offline  
Old 10-14-11, 08:14 PM
  #16  
Senior Member
 
Join Date: Jun 2009
Location: Allentown, PA
Posts: 331

Bikes: 2018 Specialized Roubaix Elite, 2009 Specialized Hard Rock 29er, 1989 Cannondale w/Campy Nuovo Record Components (mostly anway, now just on the trainer) and Easy Racer Recumbent (home made from plans)

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Probably just normal new bike cable stretching.

However depending on your size and the bike it could, as was mentioned, be frame related. I had a Tommassini, not a low end bike, that would upshift on hills. It was the frame flexing, allowed slack in the derailleur cable, upshift, couldn't pedal down I went. Happened more than once. Bought a Cannondale 3.0, this was 1989, no more problems.

Pretty sure your problem will be cured by adjustments. Good Luck.

Bill
LongT is offline  
Old 10-14-11, 08:41 PM
  #17  
Senior Member
 
Join Date: Nov 2010
Posts: 1,365
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 286 Post(s)
Liked 125 Times in 58 Posts
Originally Posted by mgw189
Ok so on the way in to work it did it again and its more a skip than it is a change of gears and I think its coming from the crank.
Did you get it at Babcock's? Take it back, they'll check it out - prob for nothing since it's only a few months old.
billyymc is offline  
Old 10-14-11, 09:05 PM
  #18  
Senior Member
Thread Starter
 
mgw189's Avatar
 
Join Date: Aug 2011
Location: Binghamtony,NY
Posts: 171

Bikes: 2011 Trek 7.3 FX

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by billyymc
Did you get it at Babcock's? Take it back, they'll check it out - prob for nothing since it's only a few months old.
Yes I did.. and they just looked at something else so I will be taking back there for a checkup again here soon... They have been awesome
mgw189 is offline  
Old 10-14-11, 09:52 PM
  #19  
Senior Member
 
rekmeyata's Avatar
 
Join Date: Sep 2010
Location: NE Indiana
Posts: 8,692

Bikes: 2020 Masi Giramondo 700c; 2013 Lynskey Peloton; 1992 Giant Rincon; 1989 Dawes needs parts; 1985 Trek 660; 1985 Fuji Club; 1984 Schwinn Voyager; 1984 Miyata 612; 1977 Raleigh Competition GS

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 1128 Post(s)
Liked 257 Times in 207 Posts
Originally Posted by mgw189
Ok so on the way in to work it did it again and its more a skip than it is a change of gears and I think its coming from the crank.
First try lubricating the chain, it may be dry, don't worry about the kind of lube just use whatever bicycle lube you have, worry about the type later. Second check the ring gear for bent or broken teeth. Next have the chain size check. If the crank itself is still skipping then you may have an issue with the bearings, which means someone may have screwed up in the assembly of the crank.

Being a new bike I would doubt the ring gear has bent or broken teeth, but it's an easy check just to eliminate it immediately. Lubing the chain would also eliminate the chain from the equation if the skipping continues afterwards. Personally I think the crank has an issue due to poor assembly, but that's why you have a warranty.
rekmeyata is offline  
Old 10-15-11, 04:36 AM
  #20  
Senior Member
 
JonnyHK's Avatar
 
Join Date: Sep 2008
Location: London
Posts: 2,420

Bikes: Baum Romano, Brompton S2, Homemade Bamboo!

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 474 Post(s)
Liked 204 Times in 129 Posts
Originally Posted by rekmeyata
First try lubricating the chain, it may be dry,
+1

A couple of tight links will cause a skip too...
JonnyHK is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mdtenor
Tandem Cycling
23
10-23-14 10:07 AM
Allen55
Clydesdales/Athenas (200+ lb / 91+ kg)
8
09-24-11 05:29 AM
goagain
Bicycle Mechanics
17
07-22-11 08:35 PM
Pipps
Road Cycling
7
05-29-11 09:34 AM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.