Go Back  Bike Forums > Bike Forums > Classic & Vintage
Reload this Page >

Help indexing a frankenbike for cyclocross

Notices
Classic & Vintage This forum is to discuss the many aspects of classic and vintage bicycles, including musclebikes, lightweights, middleweights, hi-wheelers, bone-shakers, safety bikes and much more.

Help indexing a frankenbike for cyclocross

Old 09-01-17, 08:30 AM
  #1  
hoyc
Senior Member
Thread Starter
 
Join Date: Aug 2010
Posts: 182
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 22 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Help indexing a frankenbike for cyclocross

Hi all,

On my touring bike (Nishiki Continental), I am currently running shimano 8-speed bar-ends, with a 7-speed sunrace freewheel and a Suntour Cyclone Mk II RD(the three jockey wheel model).

I was quite happy running these mismatched parts in friction mode, however I am planning on trying out some cyclocross this fall, and thought it might be beneficial to have indexed shifting.

I've tinkered a bit last night, and it didn't seem like parts were going to index nicely. However based on some searching, a 8-speed Shimano shifter should work with a 7-speed block. So I figure I will have to replace the rear mech with a Shimano unit with the correct cable-pull.

What should I be looking for in a new rear mech? Will any Shimano-unit work, or does it have to specifically be a RD made for 8-speed indexing? Also, did Shimano road and MTB RDs have the same cable-pull?

I am hoping to find something "vintage-y" to match the aesthetic of the bike. I'm open to recommendations for a specific RD to look for.
Attached Images
hoyc is offline  
Old 09-01-17, 09:33 AM
  #2  
obrentharris 
Senior Member
 
obrentharris's Avatar
 
Join Date: May 2012
Location: Point Reyes Station, California
Posts: 3,522

Bikes: Indeed!

Mentioned: 76 Post(s)
Tagged: 0 Thread(s)
Quoted: 1024 Post(s)
Liked 1,238 Times in 483 Posts
All rear Shimano rear derailleurs up to and including 9 speed have the same cable pull ratio. Things get murkier with the 10 and 11 speed.
Brent
obrentharris is offline  
Old 09-01-17, 09:43 AM
  #3  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,599

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,321 Times in 831 Posts
Vintage was Friction shifting... drop the need to have the indexing take the skill out of shifting, use the friction mode, Or

get the whole thing modify the frame to take the wider 8 speed cassette wheel and a more modern rear derailleur,

Align derailleur hanger.. STI means Shimano total integration .. want it to click ? partial/half measures wont help..


the side to side slop of 'Centron' top pulleys Shimano makes , compensates for small inaccuracies in the shifting gear to gear, being imprecise.

for one reason or another..





....

Last edited by fietsbob; 09-01-17 at 09:48 AM.
fietsbob is offline  
Old 09-01-17, 09:45 AM
  #4  
zukahn1 
Senior Member
 
zukahn1's Avatar
 
Join Date: Oct 2011
Location: Fairplay Co
Posts: 8,238

Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed

Mentioned: 21 Post(s)
Tagged: 1 Thread(s)
Quoted: 496 Post(s)
Liked 362 Times in 201 Posts
Just about any 8 speed era long cage should work for this setup. Since your going to use it on a crossbike with older parts your can pic up good used Deore DX or LX long cage fairly cheap which should work for this setup.
zukahn1 is online now  
Old 09-01-17, 09:57 AM
  #5  
T-Mar
Senior Member
 
Join Date: Nov 2004
Posts: 21,616
Mentioned: 569 Post(s)
Tagged: 1 Thread(s)
Quoted: 4033 Post(s)
Likes: 0
Liked 1,580 Times in 1,136 Posts
If they are Dura-Ace bar ends than you can run any Shimano SIS rear derailleur, though non-74xx derailleurs will require an alternate cable attachment routing. If they are not Dura-Ace ends then you can run any Shimano SIS compatible rear derailleur, with the exception of New Dura-Ace (74xx series).

Please note the cog to cog spacing on the Sunrace is actually slightly wider than 8 speed SIS spacing, Most on the difference can be accommodated by the float in the Centeron pulley but it will require careful adjustment and a properly aligned derailleur hanger.
T-Mar is offline  
Old 09-01-17, 12:26 PM
  #6  
Andy_K 
Senior Member
 
Andy_K's Avatar
 
Join Date: Jan 2008
Location: Beaverton, OR
Posts: 13,213

Bikes: Yes

Mentioned: 393 Post(s)
Tagged: 0 Thread(s)
Quoted: 2301 Post(s)
Liked 1,014 Times in 513 Posts
If you're talking about actual cyclocross racing, I would like to suggest that bar end shifters are less than ideal. You make a lot of hasty dismounts in cross, and pretty much anything that can get in your way will. There is definitely a "race what you have" culture in cyclocross, so you shouldn't let this stop you from giving it a try. Just be aware that you may end up getting jabbed in the mid-section with a blunt object a few times.
__________________
My Bikes
Andy_K is offline  
Old 09-01-17, 12:58 PM
  #7  
masi61
Senior Member
 
masi61's Avatar
 
Join Date: Oct 2005
Location: SW Ohio
Posts: 2,967

Bikes: Puch Marco Polo, Saint Tropez, Masi Gran Criterium

Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 757 Post(s)
Liked 172 Times in 133 Posts
To use the older frame as-is, I would suggest that you run with an all 7 speed indexed setup.
For cyclocross the Gevenalle (formerly Retroshift) aero levers this shifter mounts makes for a super cool solution. Get Shimano 105sc downtube levers and a used Dura Ace Freewheel & use just like a Deore XT or LX rear derailleur. Makes a super robust, crisp shifting rig that matches well with road or trekking triple cranks.
Suntour Accushift setups with 7 speed Winner Pro freewheels combined with Accushift 7 speed shift levers works great.

Last edited by masi61; 09-01-17 at 01:11 PM.
masi61 is offline  
Old 09-01-17, 01:33 PM
  #8  
hoyc
Senior Member
Thread Starter
 
Join Date: Aug 2010
Posts: 182
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 22 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Andy_K View Post
If you're talking about actual cyclocross racing, I would like to suggest that bar end shifters are less than ideal. You make a lot of hasty dismounts in cross, and pretty much anything that can get in your way will. There is definitely a "race what you have" culture in cyclocross, so you shouldn't let this stop you from giving it a try. Just be aware that you may end up getting jabbed in the mid-section with a blunt object a few times.
Thanks Andy, It'll be a mix of gravel-events and actual cyclocross. I figure I'd give it a shot first with my current set-up, and if I really like cross-racing, i could invest some more money into a dedicated set-up.
hoyc is offline  
Old 09-01-17, 01:41 PM
  #9  
hoyc
Senior Member
Thread Starter
 
Join Date: Aug 2010
Posts: 182
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 22 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by masi61 View Post
To use the older frame as-is, I would suggest that you run with an all 7 speed indexed setup.
For cyclocross the Gevenalle (formerly Retroshift) aero levers this shifter mounts makes for a super cool solution. Get Shimano 105sc downtube levers and a used Dura Ace Freewheel & use just like a Deore XT or LX rear derailleur. Makes a super robust, crisp shifting rig that matches well with road or trekking triple cranks.
Suntour Accushift setups with 7 speed Winner Pro freewheels combined with Accushift 7 speed shift levers works great.
I have looked into the Gevenalle system, and it did look like an appealing solution.

From what I've read online, 8-speed shifters should work fine on a 7-speed block, just with a "phantom click" for the extra gear, though have you had a different experience? Obviously having a full 7-speed system would be ideal, though in true C&V spirit, I'm trying to do this as cheap as possible...
hoyc is offline  
Old 09-01-17, 01:46 PM
  #10  
Andy_K 
Senior Member
 
Andy_K's Avatar
 
Join Date: Jan 2008
Location: Beaverton, OR
Posts: 13,213

Bikes: Yes

Mentioned: 393 Post(s)
Tagged: 0 Thread(s)
Quoted: 2301 Post(s)
Liked 1,014 Times in 513 Posts
Originally Posted by hoyc View Post
I figure I'd give it a shot first with my current set-up, and if I really like cross-racing, i could invest some more money into a dedicated set-up.
That's what most people do. It's a tried and true path. I got start racing on the bike I had been using as a commuter. It happened to be a CX bike, but it wasn't configured for racing. I did well enough to get me hooked on the sport. The beginners races are often full of people on everything from mountain bikes to old touring bikes, sometimes with a beach cruiser thrown in for good measure.

It's much less ridiculous than the 35+ Cat 4 field which is filled with expensive new carbon fiber CX bikes with disc brakes and tubular tires ridden by guys who really aren't any better at the sport than most of the beginners. (Full disclosure: I race 35+ Cat 4. I've managed to keep the same bike for the past 8 years so it's now old and somewhat less obviously better than I need, but its previous owner had used it to win the Cat 1 title in the big local series.)
__________________
My Bikes
Andy_K is offline  
Old 09-01-17, 01:55 PM
  #11  
masi61
Senior Member
 
masi61's Avatar
 
Join Date: Oct 2005
Location: SW Ohio
Posts: 2,967

Bikes: Puch Marco Polo, Saint Tropez, Masi Gran Criterium

Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 757 Post(s)
Liked 172 Times in 133 Posts
Originally Posted by hoyc View Post
I have looked into the Gevenalle system, and it did look like an appealing solution.

From what I've read online, 8-speed shifters should work fine on a 7-speed block, just with a "phantom click" for the extra gear, though have you had a different experience? Obviously having a full 7-speed system would be ideal, though in true C&V spirit, I'm trying to do this as cheap as possible...
7 speed shifting is just enough different (by, say 0.1mm?) that getting the 7 speed levers is going to be better shifting. These should be cheap on eBay.
masi61 is offline  
Old 09-01-17, 07:02 PM
  #12  
zukahn1 
Senior Member
 
zukahn1's Avatar
 
Join Date: Oct 2011
Location: Fairplay Co
Posts: 8,238

Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed

Mentioned: 21 Post(s)
Tagged: 1 Thread(s)
Quoted: 496 Post(s)
Liked 362 Times in 201 Posts
Also while a bit hard to find and maybe expensive the shifter's and rd the OP has would likely work fine with a Sachs Aris 7 speed freewheel but there getting pricey about $50 up for nice ones. I have sold moderately used one's with just OK gear range for $30-40 to the cheapskates here at BF's.
zukahn1 is online now  
Old 09-01-17, 07:31 PM
  #13  
hoyc
Senior Member
Thread Starter
 
Join Date: Aug 2010
Posts: 182
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 22 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by zukahn1 View Post
Just about any 8 speed era long cage should work for this setup. Since your going to use it on a crossbike with older parts your can pic up good used Deore DX or LX long cage fairly cheap which should work for this setup.
Woohoo! I was actually looking for one of these, but just managed to pick-up a Deore XT for a great price from craigslist today. It's a bit beat-up cosmetically, but feels solid. Thanks for the advice everyone!
hoyc is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
sntgatchaman
Bicycle Mechanics
10
12-28-14 10:06 AM
rugerben
Bicycle Mechanics
9
07-16-12 07:02 PM
charles1324
Bicycle Mechanics
10
05-08-10 02:02 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 - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.