Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

New chain, new 7s Uniglide cog set, skips on 3rd cog only.

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

New chain, new 7s Uniglide cog set, skips on 3rd cog only.

Old 01-22-15, 09:30 AM
  #1  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
New chain, new 7s Uniglide cog set, skips on 3rd cog only.

A few photos below.

New chain, new 7s Uniglide cog set, skips on the 3rd cog only.

Now why would it do that? Chain line is essentially at its best. No issues in, on, or off any other cog.

This is a new wheel set with a DA 7400 hub and a standard 7s cog set from NOS cogs. A very low mileage SRAM 890 did the same, only on cog 3, and I swapped out the chain.

Uniglide has these mixed height teeth in some cogs, or are these actually broken? I’ve seen enough that I presumed it was part of the design.

Does “lining up the cogs”, such as by the stamp mark happens to leave such “stubs” adjacent to one on the next cog. Would that matter?

These feel like exceedingly dumb questions, but I cannot figure this out. I cannot replicate the skipping on the stand. Only under pressure, even modest pressure.





Just pull the cog and change? But I want to understand why it is happening.

Thank you for any insights.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 09:47 AM
  #2  
Senior Member
 
Join Date: Jan 2013
Location: Llano Estacado
Posts: 3,702

Bikes: old clunker

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 684 Post(s)
Likes: 0
Liked 104 Times in 82 Posts
Maybe lube the chain?
AnkleWork is offline  
Old 01-22-15, 09:54 AM
  #3  
Senior Member
 
Join Date: Apr 2014
Location: Northeast, USA
Posts: 176

Bikes: 2015 All-City Spacehorse, 2014 Specialized Allez Race, Mid 80s Takara Acknowledge Fixed Gear

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Make sure your cable tension isn't too tight. If it's skipping on a couple teeth on the cog that may be your issue. check to ensure the chain is in-line with the cog (the teeth would ideally rest in the middle of chain).
bigredkevbot is offline  
Old 01-22-15, 09:59 AM
  #4  
Super Moderator
 
Homebrew01's Avatar
 
Join Date: Jul 2004
Location: Ffld Cnty Connecticut
Posts: 21,841

Bikes: Old Steelies I made, Old Cannondales

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 1173 Post(s)
Liked 917 Times in 605 Posts
Originally Posted by LeicaLad
New chain, new 7s Uniglide cog set, skips on the 3rd cog only.

Now why would it do that? Chain line is essentially at its best. No issues in, on, or off any other cog.

This is a new wheel set with a DA 7400 hub and a standard 7s cog set from NOS cogs. .
This is friction, non-indexed setup ??

I am guessing that due to a Campy rear derailleur with Shimano cassette.

I would start by riding it and getting it to skip. Then, without touching the shifter or anything. Put it on the stand and pedal, looking at the chain and derailleur and alignment with the cog, and look for anything bent, out of place etc ...

Is the rear derailleur meant for indexing, so the upper pulley has some float, allowing the chain to move a bit side to side ?
__________________
Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike.

FYI: https://www.bikeforums.net/forum-sugg...ad-please.html

Last edited by Homebrew01; 01-22-15 at 10:12 AM.
Homebrew01 is offline  
Old 01-22-15, 10:15 AM
  #5  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Yes. All C&V content. Friction, Suntour bar-cons.

Again, it is slipping only on the 3rd cog, where the chain line is actually as straight as possible. The chain is brand new from the wrapping and is lubbed and even Teflon coated. But this occurred with a SRAM 890, too. Also well lubbed. ONLY on the 3rd cog, a 21t, new cog.

So, feathering back and forth doesn't seem to secure the lock down. I guess there is something in that cog's specific teeth, but it is not logical and I see nothing amiss beyond those odd "stumpy" teeth.

Those ARE normal on UG cogs, yes?
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 10:20 AM
  #6  
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,772

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1752 Post(s)
Liked 1,191 Times in 829 Posts
Try flipping the 3rd cog and see if it makes a difference.
Bill Kapaun is offline  
Old 01-22-15, 10:25 AM
  #7  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Thanks. That's next. But if it works, I'll be even more mystified. I just can't figure why on that cog, and not reproducible on the stand?

Will do the cog flip or swap next.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 10:32 AM
  #8  
Senior Curmudgeon
 
FarHorizon's Avatar
 
Join Date: Jan 2005
Location: Directly above the center of the earth
Posts: 3,856

Bikes: Varies by day

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Last time I had a third cog skip, the adjacent cog was slightly bent, deflecting the chain when I tried to shift to #3 . The chain would shift down to #3 without issue, but when trying to shift up, it skipped maybe 30% of the time. I'm sure you've looked at the adjacent cogs, but just in case...
FarHorizon is offline  
Old 01-22-15, 11:09 AM
  #9  
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,772

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1752 Post(s)
Liked 1,191 Times in 829 Posts
Originally Posted by LeicaLad
Thanks. That's next. But if it works, I'll be even more mystified. I just can't figure why on that cog, and not reproducible on the stand?

Will do the cog flip or swap next.
I'd be less "mystified", since the other direction may have zero to < wear.
Bill Kapaun is offline  
Old 01-22-15, 11:16 AM
  #10  
Senior Member
 
Join Date: Dec 2010
Location: Above ground, Walnut Creek, Ca
Posts: 6,681

Bikes: 8 ss bikes, 1 5-speed touring bike

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 86 Post(s)
Likes: 0
Liked 4 Times in 4 Posts
occasionally, when i start entertaining really off the wall type of situations, i go back over things that i have previously ruled out as not possible, looking for something that i may have assumed was true, but wasn't.
hueyhoolihan is offline  
Old 01-22-15, 11:18 AM
  #11  
Senior Member
 
Join Date: Dec 2010
Location: Above ground, Walnut Creek, Ca
Posts: 6,681

Bikes: 8 ss bikes, 1 5-speed touring bike

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 86 Post(s)
Likes: 0
Liked 4 Times in 4 Posts
Originally Posted by LeicaLad
Thanks. That's next. But if it works, I'll be even more mystified. I just can't figure why on that cog, and not reproducible on the stand?

Will do the cog flip or swap next.


it's very hard to duplicate a problem that only manifests itself under load, when the bike is on the stand.

Last edited by hueyhoolihan; 01-22-15 at 06:04 PM.
hueyhoolihan is offline  
Old 01-22-15, 11:24 AM
  #12  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Originally Posted by Bill Kapaun
I'd be less "mystified", since the other direction may have zero to < wear.
Cogs are new, meaning less than 100 miles. Chain is new, meaning less than 10 miles of shake down.

Under careful and magnified eye-balling, I see nothing crooked, bent, nor nuthin'

I'll flip 'em first, then I'll swap out for other NOS cogs.

Just strange. Thanks for encouragement as I go.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 11:28 AM
  #13  
Senior Member
 
ljsense's Avatar
 
Join Date: Sep 2009
Location: Madison, Wis.
Posts: 755
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 152 Times in 92 Posts
Since this problem happened with your other cog set (the SRAM one you mentioned) I'd be surprised if it were related to the cogs.

And since it happens under load, I would think about things that might change with pedaling force.

Maybe your frame is flexing and applying force on the shift cable. I don't know why that would only affect the third gear, but maybe this is the one that's most eager to shift, since the chain is neutral here and easy to bend in either direction.

Also, maybe the cable housing is doing something as you pedal. Bar end cable housing is pretty long and can do stuff when you're riding.

Just a few quick ideas for your consideration
ljsense is offline  
Old 01-22-15, 11:29 AM
  #14  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,396

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 138 Post(s)
Tagged: 1 Thread(s)
Quoted: 5627 Post(s)
Liked 2,248 Times in 1,261 Posts
New chain/old sprocket is classic for shipping.

With wear the rollers create pockets at the base of the teeth. That allows the chain to settle deeper and the next roller ends up bumping the corner as it meets the teeth. That causes it to climb up and ride the top, until the pitches line up tha the chain can engage. That's why you get the one link skip.

If the skipping is very minor and you can live with it, ride the bike, and the bumping roller will wear the offending corner, and the problem will solve itself. Or you can use a Dremel to break the back corners of all the teeth on the problem sprocket, and solve it immediately (but it's a slow process).
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Old 01-22-15, 11:38 AM
  #15  
Senior Member
 
ljsense's Avatar
 
Join Date: Sep 2009
Location: Madison, Wis.
Posts: 755
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 152 Times in 92 Posts
op says both the cogs and the chain are new, and the same thing happened on a different cog set that had low mileage
ljsense is offline  
Old 01-22-15, 11:40 AM
  #16  
Senior Member
 
ljsense's Avatar
 
Join Date: Sep 2009
Location: Madison, Wis.
Posts: 755
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 152 Times in 92 Posts
Can you check the alignment of the derailleur hanger?
ljsense is offline  
Old 01-22-15, 11:49 AM
  #17  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Originally Posted by ljsense
op says both the cogs and the chain are new, and the same thing happened on a different cog set that had low mileage
Same cogs, different chain. It's a new wheel. NOS cogs. NEW. Did a couple modest rides with SRAM chain. Skipping on 3rd cog. That chain was a few months old, very modest mileage. Thus, the cogs maybe have 100 miles, but I'd guess less. That SRAM chain, maybe 500-600 miles. Darn near new.

But, I still traded that out for a Brand New fancy schmancy Wipperman chain. Same result.

I'm swapping around the cogs, but can't get out to test right now. (Duty bound.) Derailleur has been no problem on other wheels, mostly 6s or 7s Freewheel equipped.

It's an odd one.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 11:50 AM
  #18  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,396

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 138 Post(s)
Tagged: 1 Thread(s)
Quoted: 5627 Post(s)
Liked 2,248 Times in 1,261 Posts
Originally Posted by ljsense
op says both the cogs and the chain are new, and the same thing happened on a different cog set that had low mileage
I missed the second "new".

Then it's probably a simple profile or stiff chain issue. Since it's only on a single sprocket, I'd see if I could live with long enough for break-in wear to fix it.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Old 01-22-15, 11:54 AM
  #19  
Senior Member
 
ljsense's Avatar
 
Join Date: Sep 2009
Location: Madison, Wis.
Posts: 755
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 152 Times in 92 Posts
whoops i misread. try a different cog set
ljsense is offline  
Old 01-22-15, 11:55 AM
  #20  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Originally Posted by FBinNY
I missed the second "new".

Then it's probably a simple profile or stiff chain issue. Since it's only on a single sprocket, I'd see if I could live with long enough for break-in wear to fix it.

Thanks. I'll flip the cogs to see if it is the same, but I may try the "patience" route next.

As always, thank you for the generosity of suggestions.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 02:10 PM
  #21  
working on my sandal tan
 
ThermionicScott's Avatar
 
Join Date: Aug 2011
Location: CID
Posts: 22,612

Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)

Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3867 Post(s)
Liked 2,549 Times in 1,570 Posts
Originally Posted by LeicaLad
Uniglide has these mixed height teeth in some cogs, or are these actually broken? I’ve seen enough that I presumed it was part of the design.
Could you take some dedicated pictures of the "stumpy" teeth? I was under the impression that Uniglide teeth were all the same -- full height and twisted.
__________________
Originally Posted by chandltp
There's no such thing as too far.. just lack of time
Originally Posted by noglider
People in this forum are not typical.
RUSA #7498
ThermionicScott is offline  
Old 01-22-15, 04:36 PM
  #22  
Senior Member
Thread Starter
 
Join Date: Jun 2010
Location: Work in Asia, now based in Vienna, VA
Posts: 1,758
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 35 Times in 23 Posts
Solution achieved, but mystery remains.

A new set of cogs and it shifts flawlessly. I got a quick 30 mins. out for a sprint, and nary a single slip nor chatter. Can't make it skip.

When I pulled the previous cluster off, I'd forgotten that the upper five cogs were pinned. Yes, I could unpin them, but it was easier to quick grab a group of loose cogs and throw 'em on. Also all NOS cogs. SO, the obvious answer is that there is something among those pinned cogs. That was a NOS set I'd purchased a while back. Who knows what warp or pinch, but my eye hasn't seen it yet. I've looked from every angle but still stumped. I'll take it apart on a cold night.


Originally Posted by ThermionicScott
Could you take some dedicated pictures of the "stumpy" teeth? I was under the impression that Uniglide teeth were all the same -- full height and twisted.
Ask and ye shall receive. The short and slightly wider teeth seem to appear only on the 21t and larger cogs. I've just dug through a box of new cogs, including a set pulled from box and virgin wrapping plastic. They all have them above 21t.

Two photos.





Both images the same two 21t cogs. This was Q&D.

They have another on the other side, but not directly.
__________________
1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)
LeicaLad is offline  
Old 01-22-15, 09:31 PM
  #23  
working on my sandal tan
 
ThermionicScott's Avatar
 
Join Date: Aug 2011
Location: CID
Posts: 22,612

Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)

Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3867 Post(s)
Liked 2,549 Times in 1,570 Posts
Thanks! Given that they're in the same position and cut straight across, it must be intentional -- probably to aid shifting. I've learned something new, and am going to re-inspect my Uniglide freewheel(s) to see if it/they have similar teeth.
__________________
Originally Posted by chandltp
There's no such thing as too far.. just lack of time
Originally Posted by noglider
People in this forum are not typical.
RUSA #7498
ThermionicScott is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Countdown48
Bicycle Mechanics
10
04-20-16 11:54 AM
Steve Whitlatch
Bicycle Mechanics
18
01-02-14 09:18 PM
swapmeet
Bicycle Mechanics
2
05-05-11 11:58 AM
TurbineBlade
Bicycle Mechanics
8
10-25-10 06:53 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.