"popping" rear cogset

Where to ask questions on riding skills, training, nutrition, and bike repair

"popping" rear cogset

Postby bbender785 » May 23rd, 2013, 1:23 pm

so the bike i've been riding since 1998 has had this issue since i bought it new, and i've just never done anything about it. has a 7-speed rear cogset with a shimano STX derailleur, and whenever it is in the 6th or 7th gear the drivetrain "pops" under heavy torque. i've had the bike LBS-tuned multiple times over the years and have tried to trail-adjust it many a time as well, with no improvement.

is this a derailleur issue or something in the casette do you think? i'd love to get this bike in running order so i can maybe sell it, or have it for friends to ride.
AIRBORNE Guardian
User avatar
bbender785
 
Posts: 63
Joined: December 12th, 2012, 11:48 am
Location: Dutton, MI

Re: "popping" rear cogset

Postby plunderspunk » May 23rd, 2013, 5:57 pm

I would check to see if the teeth on the 6 and 7 gear are worn.
A.K.A. Geardaddy
plunderspunk
 
Posts: 3228
Joined: May 7th, 2014, 10:02 pm

Re: "popping" rear cogset

Postby Critter7r » May 23rd, 2013, 7:08 pm

Have you ever put a new cassette on it? Chain?

I assume that since it's done it since new that the chain isn't skipping, but maybe the 6&7 sprocket don't mesh well with the splines. If you've put a new cassette on it and it still does it, then it must be either inside the freewheel, or the splines are jacked.
<> Chris <>
I live in Holly & ride my '02 FSR 26'er '09 Trek Fuel 26'er at Holdridge.
Critter7r
 
Posts: 1226
Joined: November 9th, 2010, 4:24 pm

Re: "popping" rear cogset

Postby Bikelaura » May 23rd, 2013, 11:08 pm

Have you adjusted the B screw to increase the chain wrap? Some older frames have the derailleur mount too far aft of the axle to allow for enough chain wrap and then that leads to the symtoms you describe. One easy solution is to not climb in that gear. ;-) Hope this helps.
Bikelaura
 
Posts: 155
Joined: February 8th, 2005, 10:22 pm
Location: Holland, MI

Re: "popping" rear cogset

Postby scat silvurz » May 23rd, 2013, 11:46 pm

worn out....you just got used to how sucky it is.
Five fingers, three chords, and one *beep*.....!
Image
User avatar
scat silvurz
 
Posts: 7992
Joined: January 20th, 2003, 11:24 pm

Re: "popping" rear cogset

Postby bikerector » May 24th, 2013, 8:29 am

I would also check the derailleur hangar alignment, if none of the other options fix it. I'm thinking b-screw if it was like that when it was new. If you've never replaced the chain or cassette since 1998, might be time for those too.
"Life is what we make it"
http://www.cyclingandsuffering.com
User avatar
bikerector
 
Posts: 950
Joined: August 3rd, 2012, 8:03 am
Location: Holland, MI

Re: "popping" rear cogset

Postby okeja » May 24th, 2013, 10:18 am

Sounds to me like it is probably in just fine running order already. Why fix a problem that has been present since the bike was new and has not stopped you from riding it those 15 years ??

I third that b-screw & chain wrap is best place to start. Possible it is a chainline issue as well. Or combination.
...but it also seems that the LBS mechanic(s) tuning the bike multiple times would have checked these already when you described the popping occurance to them.

Is it actually a pop with a skip involved? Or does it just make a popping noise?



Regarding the Airborne - sell the old popping bike and a few other items around the house; be sure she is aware you are selling the stuff; then pull the Airborne from the shed and tirumphantly tell her how you used the money from selling the old stuff to pay for it
okeja
 
Posts: 655
Joined: May 28th, 2004, 10:05 am
Location: Rockford

Re: "popping" rear cogset

Postby bbender785 » May 24th, 2013, 10:43 am

okeja wrote:Sounds to me like it is probably in just fine running order already. Why fix a problem that has been present since the bike was new and has not stopped you from riding it those 15 years ??


because i could not bring myself to selling it like that should i send it down the road. and if i do keep it, i don't want the newb that would likely be piloting it to have a bad experience. it also needs a rear shock overhaul (seals are out, and it's an air shock), a tube, rear linkage bushings, fork could stand a rebuild (or replacement really.. RS Quadra 5), etc.. thats another story.

I third that b-screw & chain wrap is best place to start. Possible it is a chainline issue as well. Or combination.
...Is it actually a pop with a skip involved? Or does it just make a popping noise?


sounds like this b-screw is my first plan of attack. it does skip, quite violently. that's why it's a concern.. i could live with it if it was just making noise.



Regarding the Airborne - sell the old popping bike and a few other items around the house; be sure she is aware you are selling the stuff; then pull the Airborne from the shed and tirumphantly tell her how you used the money from selling the old stuff to pay for it


yeah.. still thinking on that one. :lol:
AIRBORNE Guardian
User avatar
bbender785
 
Posts: 63
Joined: December 12th, 2012, 11:48 am
Location: Dutton, MI

Re: "popping" rear cogset

Postby Roy » May 27th, 2013, 6:42 pm

Is the frame worth all new components? ( no cracks)
Can you find new pivot bearings? (probably the root cause of the popping)
Can the rear shock be replaced? ( to old )
Can you live without disc brakes? ( no attachments points)
Can you spend a lot of money on this bike? (your call)

One NO, put it on the curb on garbage day!
User avatar
Roy
 
Posts: 1557
Joined: August 14th, 2002, 9:04 pm

Re: "popping" rear cogset

Postby Longbow » May 27th, 2013, 7:20 pm

I have a brand new Giant XTC and it was doing the same thing today. Taking it in to see if they can figure it out this Saturday.
Longbow
 
Posts: 2
Joined: May 27th, 2013, 11:32 am


Return to Tips, Training & Techniques

Who is online

Users browsing this forum: No registered users and 1 guest