Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

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.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-24-11, 10:28 AM   #1
Purp
Senior Member
Thread Starter
 
Join Date: Oct 2007
Bikes:
Posts: 97
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
130mm hub in Dropouts Spaced to 135mm: no Bending or Respacing, Recipe for Disaster?

Hey BF,

I have a frame with 135mm spacing in the rear, and I wanted to use my existing wheel, which has a 130mm-wide hub. I'm trying to avoid cold-setting/respacing if possible.

One option is to just clamp down the dropouts to the 130mm spacing using the axle locknuts on the outside of the dropouts. I wanted to avoid this because it seemed like it would mean the dropouts were no longer parallel.

My current solution is adding a 2.5mm spacer washer to both sides of the hub:


http://i.imgur.com/Ibl6c.jpg

...making to overall hub "width" 135mm. This solves the issue of having to bend the dropouts, but now there is only a very slight amount of the axle remaining to actually sit in the dropouts:


http://i.imgur.com/S76V6.jpg

(The quick-release axle running through the hub axle is long enough to span the entire length, of course)

Is this a recipe for disaster? Will this put undue stress on my hub, or cause the wheel to pop out, or something similar? Is this silly, and I should just bend the dropouts inwards using the outer locknuts?

On a related note, The Great Sheldon (pbuh) says:

Quote:
if you're installing a derailer-type wheel in a wider frame than it was meant for, you should add the spacers to the left side. This will allow you to increase the strength of the wheel by moving the rim to the left.
But wouldn't this move the wheel off center, and require re-dishing? Isn't it easier just to add even space on both sides?
Purp is offline   Reply With Quote
Old 04-24-11, 10:40 AM   #2
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 29,113
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 176 Post(s)
You have enough axle protrusion to hold the wheel properly. A "proper" axle is 11 mm longer than the OLD spacing and allows 5.5 mm to stick out each end. Adding 5 mm of spacer reduces the protrusion to 3 mm per side which is sufficient.

As to the spacer location, adding spacers to both sides often upsets the chainline enough to cause shifting problems so the better way is to add all of the spacers to the non-drive side and redish the rim. If you aren't having shifting or chain rubbing problems, you can leave the wheel as you have it. Sheldon is correct that adding all of the spacers to the NDS will allow a wheel with less dish and, therefore, it will be stronger.
HillRider is offline   Reply With Quote
Old 04-24-11, 11:06 AM   #3
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 30,838
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 862 Post(s)
Using shims or not and how to use them depends on whether this will be a regular thing or not.

For occasional use, don't add any shims and simply flex the frame. It'll be somewhat harder mounting the wheel, but you can accept that. The dropout parallelism issue is minor, involving an error of about 1/2° or less.

People have been using the flex method for 126/130mm and another millimeter isn't going to be a dealbreaker.

-------------

If this is going to be the regular wheel for this frame, you'll probably want to either coldset the frame, or shim the wheel, if only for easier mounting.

If you do shim you have decisions, as Hillrider pointed out. Shimming each side is easy, and there's no issue of axle support, but chainline and RD travel might (that's might, but equally likely, might not) become issues with the cassette moved inboard 2.5mm.

OTOH shimming all on the left, which is the better method, means re-dishing the wheel and moving the axle over, which doesn't seem to be an option for you based on the photo.

If you don't or can't move the axle 5mm all on the left means zero axle/frame support and may be OK for a short while on good roads, but no more than that.

You could consider splitting the difference and adding thinner shims to both sides, or 3mm all on the left but not-re-dishing, and I think something along either of those lines may be the best approach.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“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.

Last edited by FBinNY; 04-24-11 at 11:11 AM.
FBinNY is online now   Reply With Quote
Old 04-25-11, 08:08 AM   #4
Purp
Senior Member
Thread Starter
 
Join Date: Oct 2007
Bikes:
Posts: 97
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Perfect, just the info I needed, thanks all.
Purp is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 11:06 PM.