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

crank spider contacting chain on singlespeed

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.

crank spider contacting chain on singlespeed

Old 07-16-13, 08:42 PM
  #1  
sirtirithon
Senior Member
Thread Starter
 
sirtirithon's Avatar
 
Join Date: Apr 2011
Location: Spokane
Posts: 279
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
crank spider contacting chain on singlespeed

I just had my bike converted to single speed. Crank is a Shimano XT M785 and chain ring is a stainless shimano 32T. I'm running a Surly 18t in back. Love the ratio. I noticed the chain is slightly contacting the crank spider though and has worn off the finish a bit. Is this a problem? I am having no performance issues it appears to be cosmetic at this point but as the chain wears down or the teeth on the chainring could it become a problem? Can I solve this by installing chainring spacers between the spider and chainring? Or am I just making an issue out of nothing? Thanks!












sirtirithon is offline  
Old 07-16-13, 09:03 PM
  #2  
JohnDThompson 
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Posts: 20,360

Bikes: Several, mostly not name brands.

Mentioned: 107 Post(s)
Tagged: 0 Thread(s)
Quoted: 1664 Post(s)
Liked 39 Times in 25 Posts
No, it shouldn't be a problem as long as the chain stays properly seated as it passes over the spider.
JohnDThompson is offline  
Old 07-16-13, 09:12 PM
  #3  
sirtirithon
Senior Member
Thread Starter
 
sirtirithon's Avatar
 
Join Date: Apr 2011
Location: Spokane
Posts: 279
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by JohnDThompson View Post
No, it shouldn't be a problem as long as the chain stays properly seated as it passes over the spider.
It appears to be properly seated as it goes around. No skipping issues. The spider is literally flush with the chainring. It looks like it is getting full tooth engagement when the chain passes over this area.
sirtirithon is offline  
Old 07-17-13, 12:35 AM
  #4  
DX-MAN
Banned
 
Join Date: Jun 2009
Posts: 4,788
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
If it BECOMES a problem, and you like the gear combo, you'll have to swap ring and cog; BikeCalc.com says 36/20 is pretty much identical.
DX-MAN is offline  
Old 07-17-13, 12:44 AM
  #5  
tomacropod
ot.net slave
 
Join Date: Feb 2006
Location: Canberra, Australia
Posts: 571

Bikes: Salsa mtb * 3, Intense mtb * 1, Abeni SS rd * 1, Salsa road/touring * 2, Trek Damn one * 1, Vintage/projects * many

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
You won't have to swap the cog, just file a chamfer onto the spider where it contacts.

- Joel
tomacropod is offline  
Old 07-17-13, 05:04 AM
  #6  
dsbrantjr
Senior Member
 
dsbrantjr's Avatar
 
Join Date: Sep 2010
Location: Roswell, GA
Posts: 6,157

Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta

Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 629 Post(s)
Likes: 0
Liked 30 Times in 28 Posts
The chain will likely wear itself a recess on the spider. If you'd like you could take a Dremel tool with a drum-shaped tool and finish the job yourself. If your chainline permits you could also use "chainring spacers" to shim the ring away from the spider until the chain clears it.
dsbrantjr is offline  
Old 07-17-13, 10:13 AM
  #7  
Grand Bois
Senior Member
 
Grand Bois's Avatar
 
Join Date: Mar 2005
Location: Pinole, CA, USA
Posts: 17,421
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 428 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Spacers will foul up your chainline. I'd pull off the crank and spend a few minutes with the bench belt sander.
Grand Bois is offline  
Old 07-17-13, 10:40 AM
  #8  
zandoval 
Senior Member
 
zandoval's Avatar
 
Join Date: May 2010
Location: Bastrop Texas
Posts: 1,788

Bikes: Univega, PR-10, Ted Williams,UO-8, Puch, PHLE, UO-18 Mixte

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by dsbrantjr View Post
The chain will likely wear itself a recess on the spider...
Maybe consider using an economical chain till it does and really it won't take long...
zandoval is offline  
Old 07-17-13, 10:55 AM
  #9  
JohnDThompson 
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Posts: 20,360

Bikes: Several, mostly not name brands.

Mentioned: 107 Post(s)
Tagged: 0 Thread(s)
Quoted: 1664 Post(s)
Liked 39 Times in 25 Posts
Originally Posted by tomacropod View Post
You won't have to swap the cog, just file a chamfer onto the spider where it contacts.

- Joel
That's essentially what Ofmega/Avocet did to accommodate a 41T ring on their 144mm BCD spider:

JohnDThompson is offline  
Old 07-17-13, 11:38 AM
  #10  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,613

Bikes: 8

Mentioned: 183 Post(s)
Tagged: 0 Thread(s)
Quoted: 6757 Post(s)
Likes: 0
Liked 164 Times in 140 Posts
yea, File off the needed clearance, from the end of the crank spider .

Might want to have the crank off the bike to do a good job..
fietsbob is offline  
Old 07-17-13, 12:15 PM
  #11  
sirtirithon
Senior Member
Thread Starter
 
sirtirithon's Avatar
 
Join Date: Apr 2011
Location: Spokane
Posts: 279
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks for the advice! I am going to take it by the LBS and try a set of 2mm chainring spacers between the chainring and spider and see if that gives enough clearance. I have a Surly SS kit in the rear so I can easily adjust the chain line to keep it straight afterwards. This would also benefit me by gaining a couple more MM's clearance at my chain stay for the chain as its a bit close anyways.
sirtirithon is offline  
Old 07-17-13, 01:13 PM
  #12  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,613

Bikes: 8

Mentioned: 183 Post(s)
Tagged: 0 Thread(s)
Quoted: 6757 Post(s)
Likes: 0
Liked 164 Times in 140 Posts
I have a Surly SS kit in the rear
some tweaking of axle spacers and wheel re-dish could move the chainline on the hub over ,
were it not a single- speed-on- a- Cassette hub, conversion..
clearance at my chain stay for the chain as its a bit close anyways.
You mean the dropout end, at the back, right?
fietsbob is offline  
Old 07-17-13, 07:57 PM
  #13  
sirtirithon
Senior Member
Thread Starter
 
sirtirithon's Avatar
 
Join Date: Apr 2011
Location: Spokane
Posts: 279
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Update. Went by the LBS and they installed 4mm spacers and new bolts. Worked great! Adjusted the spacers in the rear for the new chain line and all is good now! Thanks guys!!! Hope this helps someone else if they run into this issue.






sirtirithon is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Gary Fountain
Classic & Vintage
16
07-02-11 09:44 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.