Have questions or want to discuss cycling? Join Now or Sign In to participate in the BikeRide community.

New: Take Part in the new April's Giveaway for a Chance to Win the Euybike S4 Pro Max ebike worth $1299


Front derailleur - how to increase travel?
#1
How do I increase the travel of the front derailleur?

I had to replace the bottom bracket. The new spindle is longer than the one I replaced. Now, I can't get sufficient travel to move the chain to the outside chainring (of a double).

I've backed the limit screw out as far as it will go. The arm of the derailleur hits the body of the derailleur itself. There is no more room to give.

Do I need to replace the derailleur? If so, what kind of information do I need to find a derailleur with sufficient travel.

Thanks,
  Reply
#2
I suspect you'll probably have to find a shorter spindle. I assume some derailleurs have slightly more travel than others, but I don't know of any way to determine it other than trial and error.

If your BB is a three piece cup and spindle type, you might be able to just put it in the other way. A lot of spindles are longer on the drive side so reversing it would bring the crank closer to the frame. It would push your left leg out farther which isn't ideal, but not that big a deal.
  Reply
#3
Dave has it covered.

You may be able to find a MTB front derailleur intended for a triple that will go far enough out, but most are limited to 48T is the biggest chain ring.

There is a reason that crank sets suggest a certain length of BB axle......

If you have a "sealed" bottom bracket, you'll need to get another one, the correct length.
http://www.amazon.com/Shimano-BB-UN54-Square-Bottom-Bracket/dp/B0014C4G58/

Here is an example of what Dave mentioned:
http://www.amazon.com/Pyramid-Bottom-Bracket-Axle-Type/dp/B000BMNQVW/
they are available in different lengths and offsets.
Nigel
  Reply


Possibly Related Threads...

Forum Jump:

[-]
10 Latest Posts
Wearable Fitness Trackers
Today 01:24 PM
First Metric Century
Today 12:31 PM
Gu/SiS/Energy Gels replacement
Today 07:55 AM
Ride and Remember
Yesterday 08:52 PM
Front derailer not moving
Yesterday 08:49 PM
Dropper Post: Pros and Cons
Yesterday 05:03 PM
What are the best cost effective ways to...
05-08-2025 09:33 PM
Dropper Post: Hints and Tips
05-08-2025 07:59 PM
Hoping someone can help me identify this...
05-07-2025 05:47 PM
How to deal with rusty chain
05-07-2025 12:50 PM

[-]
Join BikeRide on Strava
Feel free to join if you are on Strava: www.strava.com/clubs/bikeridecom

[-]
Top 5 Posters This Month
no avatar 1. Painkiller
23 posts
no avatar 2. Flowrider
18 posts
no avatar 3. meamoantonio
16 posts
no avatar 4. enkei
16 posts
no avatar 5. SPINMAN
14 posts