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 09-27-10, 08:25 PM   #1
trek330
Senior Member
Thread Starter
 
Join Date: Apr 2010
Location: New York City
Bikes:
Posts: 728
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Switching rims

Can I switch a double walled 622-15 rim with a 622-17 single walled rim without changing spokes?The spokes are new.Do I need different nipples?The 622-17 is the presently installed rim and the 622-15 would be an upgrade.Thanks!
trek330 is offline   Reply With Quote
Old 09-27-10, 08:33 PM   #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: 28,776
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
It's unlikely the spoke would be the correct length.
HillRider is offline   Reply With Quote
Old 09-27-10, 08:36 PM   #3
Al1943
Senior Member
 
Join Date: Feb 2005
Location: Oklahoma
Bikes: Trek 5500, Colnago C-50
Posts: 9,433
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You need to compare the ERD of the two rims. This information is available at various sites for many rims.
Al1943 is offline   Reply With Quote
Old 09-27-10, 08:45 PM   #4
BikeWise1
30 YR Wrench
 
BikeWise1's Avatar
 
Join Date: Aug 2005
Location: Oxford, OH
Bikes: Waterford R-33, Madone 6.5, Trek 520
Posts: 2,006
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
+1. The fact this question is being asked is indicative of someone who probably isn't aware of the relationship between things like ERD and spoke length.

If that's the case, the OP probably shouldn't be building own wheels just yet. But that's just the opinion of someone who builds lots of wheels.......for a living.......

OP, this question cannot be answered without more information.
BikeWise1 is offline   Reply With Quote
Old 09-28-10, 01:07 AM   #5
trek330
Senior Member
Thread Starter
 
Join Date: Apr 2010
Location: New York City
Bikes:
Posts: 728
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by HillRider View Post
It's unlikely the spoke would be the correct length.
I'm going to assume this is the definitive answer.I thought perhaps the "622"would be the workable measure and therefore doable.I just purchased a truing wheel and tensionmeter and am determined to learn truing and eventually wheel building since I'm so dissatisfied with NYC mechanics.Of course I plan on practicing on some old wheels before I doit seriously on a working bike.
trek330 is offline   Reply With Quote
Old 09-28-10, 01:36 AM   #6
dabac
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 5,361
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Quote:
Originally Posted by trek330 View Post
Can I switch a double walled 622-15 rim with a 622-17 single walled rim without changing spokes?
Unlikely. 622 refers to the bead seat diameter, basically where the tire meets the rim. There's no fixed relation between the BSD and the requires spoke length. 15/17 refers to rim internal width, which has a so-so relationship to which width of tires you can run on a certain rim.

The value you want to be looking for is (quote from Sheldon Brown) Effective Rim Diameter. This is the rim diameter measured at the nipple seats in the spoke holes, plus the thickness of the two nipple heads. The E.R.D. is needed for calculating the correct spoke length.

A rim with a higher profile will have a lower ERD despite being the same BSD.

Do note that all suppliers measure ERD in the same way, and don't take for granted that values listed on websites are correct.

Sometimes picking another lace pattern can offer possibilities. Going from 3-cross double wall to 2-cross single wall might free up enough spoke length for a successful transplant. Or 3X single-wall to 4X double wall might use up enough spoke for the wheel to tension up properly.

Different nipple lengths can, IME, be used for minor tweaks of spoke lengths. However, not all would agree, and for a first build you want things to line up nicely w/o any extra challenges.
dabac is offline   Reply With Quote
Old 09-28-10, 01:46 AM   #7
Bezalel
Senior Member
 
Join Date: Mar 2010
Location: City of Brotherly Love
Bikes: Raleigh Companion, Nashbar Touring, Novara DiVano, Trek FX 7.1, Giant Upland
Posts: 1,508
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'm with HillRider. Since one of the rims is single walled and the other is double walled, it is extremely unlikely that they have the same ERD.
Bezalel is offline   Reply With Quote
Old 09-28-10, 09:44 AM   #8
peripatetic
Senior Member
 
peripatetic's Avatar
 
Join Date: Oct 2004
Location: NYC
Bikes: All 70s and 80s, only steel.
Posts: 2,124
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
http://www.sheldonbrown.com/wheelbuild.html#length

http://www.wheelpro.co.uk/spokecalc/
peripatetic is offline   Reply With Quote
Old 09-28-10, 04:11 PM   #9
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,543
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Quote:
Originally Posted by trek330 View Post
Of course I plan on practicing on some old wheels before I doit seriously on a working bike.
I hear that a lot but I think that it's a bad plan.

You can practice the actual laceing function using an old wheel but I could train a chimpanzee to do that part.

The real wheelbuilding process starts after the wheel has been laced. Getting all of the spokes to equal and even tension is what we're after. If you are practicing with an old wheel, the rim is likely to be egg shaped and out-of-true. I don't think that you can teach yourself to tension and true a wheel properly using a crappy rim. Since you've already spent money on tools, have the confidence to start with decent quality hub, rim and spokes. If you take your time and sweat the details there is no reason why your first wheel shouldn't rival the quality of anything that you can buy.
Retro Grouch 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 09:18 AM.