Go Back  Bike Forums > Bike Forums > Mountain Biking
Reload this Page >

San Francisco Globe problem

Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

San Francisco Globe problem

Old 11-29-17, 08:47 AM
  #1  
vivvov
Senior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 104
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
San Francisco Globe problem

Hi there..A friend has purchased a second hand San Francisco Globe and the chain keeps coming off the front chain ring every time the bike's in highest gear...any ideas?
He's played about with rear derailleur but still the same problem.
Thanks in advance.
vivvov is offline  
Old 11-29-17, 09:24 AM
  #2  
2cam16
Senior Member
 
2cam16's Avatar
 
Join Date: Oct 2016
Location: San Mateo,Ca.
Posts: 2,550

Bikes: TOO MANY

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 579 Post(s)
Liked 25 Times in 22 Posts
The H limit screw probably needs adjusting.
2cam16 is offline  
Old 11-29-17, 01:08 PM
  #3  
jan230
Old Rider
 
jan230's Avatar
 
Join Date: Nov 2010
Location: North Shore
Posts: 84
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Just to confirm,this is a Specialized brand bike and does not have a front derailleur?
jan230 is offline  
Old 12-12-17, 06:12 AM
  #4  
vivvov
Senior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 104
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Hi ..that;s right..It's a single chain ring on the crank set..with no front derailleur.
The chain just keeps missing the teeth in highest rear gear..so I adjusted the rear derailleur to avoid the highest gear, as a stop gap measure, but when my friend attempted to ride it..off it came again.
Crank set looks like it could accommodate an inner chain ring so thought I might swap the chain ring to the inner position to move it towards the frame 5mm or so and thereby straighten up the chain angle from front to back..but it's odd that it's doing it in the first place.
vivvov is offline  
Old 12-12-17, 07:18 AM
  #5  
JonathanGennick 
Senior Member
 
JonathanGennick's Avatar
 
Join Date: Apr 2007
Location: Munising, Michigan, USA
Posts: 3,987

Bikes: Priority 600, Priority Continuum, Devinci Dexter

Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 632 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by vivvov View Post
Crank set looks like it could accommodate an inner chain ring so thought I might swap the chain ring to the inner position to move it towards the frame 5mm or so and thereby straighten up the chain angle from front to back..but it's odd that it's doing it in the first place.
Wouldn't moving the ring to the inner position actually increase the angle to the high gear? When you say "high gear", are you talking about the small cog?

Is there slack in the chain when in the small cog? Is the chain the stock chain? Does the freehub backpedal freely? I've had instances where backpedaling would cause a chain to drop, and it's surprising how often one moves one's feet in the opposite direction w/o thinking about it.
JonathanGennick is offline  
Old 12-12-17, 02:08 PM
  #6  
prj71
Senior Member
 
Join Date: Jun 2015
Posts: 1,600
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 876 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
You need an narrow/wide chain ring if the front derailleur has been been removed.

To me it sounds like the derailleur was removed and inner the chainring was removed from the inner position on the crank...ghetto 1x conversion.

https://mbaction.com/a-guide-to-narrow-wide-chainrings/
prj71 is offline  
Old 12-18-17, 12:25 PM
  #7  
GrainBrain
Senior Member
 
GrainBrain's Avatar
 
Join Date: Aug 2017
Location: Central Io-way
Posts: 1,188

Bikes: LeMond Zurich, Giant Talon 29er

Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 627 Post(s)
Likes: 0
Liked 27 Times in 17 Posts
It looks like this is some kind of Urban bike with no FD from factory.

I would check the rear derailleur hanger if it's been bent. From there I'd check the RD set screws.

Can you post pictures or at least what your RD is?
GrainBrain is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
YamiRider1316
Mountain Biking
13
03-30-13 06:48 AM
Mike_Hunt
BMX
0
06-21-10 07:31 PM
mzeffex
"The 33"-Road Bike Racing
0
01-13-10 08:15 PM
Pamestique
United Kingdom
1
08-07-08 04:28 PM
stormchaser
Road Cycling
0
02-02-06 05:37 PM

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


Thread Tools
Search this Thread

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

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.