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

New: Take part in the February Giveaway for a Reflective Backpack & Spine Protector from RiderBag


Install bigger crank chain wheel on mountain bike
#1
Hi,

I have a mountain bike thr has a 32 tooth chainwheel on the crank i would like to put a bigger 48 on to the crank axke i. Order to cycle the higher road speeds easier, if you install it in the exact place where you take off the old one it will not fit as it will touch the frame, because the crank is mounter in a indent of the spreader if the framer, is thete a such thing as a longer crank axle or a crank axle extender ?

Regards joe
  Reply
#2
Pictures would help here, but if you use a longer spindle it will affect chainline.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
  Reply
#3
(02-15-2021, 12:46 PM)Joe Crean Wrote:  Hi,

I have a mountain bike that has a 32 tooth chainwheel on the crank; i would like to put a bigger 48 on to the crank axle in order to make cycling at higher road speeds easier. If you install it in the exact place where you take off the old one it will not fit as it will touch the frame, because the crank is mounted in an indent on the chainstay of the frame. Is there a such thing as a longer crank axle or a crank axle extender ?

Regards joe

Hi Joe,
The previous comment applies. It would depend on how much farther out the chainring must be positioned. A millimeter or 2 should not be to bad. It might also depend on which gears (front and rear) that you primarily use; if you tend to ride your large chainring and smaller rear cogs you might find that your chainline is actually a little better, but otherwise the bike will be noisier and cause more wear to your chain and sprockets if the chainline is too far off when using gears that emphasize the misalignment. Have you checked about changing (getting smaller sizes) for any of the rear cogs? This will not affect the chainline as would a front modification. You might also be able to install spacers/shims between the chainring and the crank spider at the chainring bolt mounts, or between the crankarm and spindle (depending on mounting style), thus effectively providing more clearance with the frame. Is the 32 tooth ring your largest ring (I assume you have a double or triple chainwheel? Seems small for the large ring; if it is the middle or smallest ring I would recommend different shifting/gear selection to provide the resistance you desire.
Ride Fast, Be Safe!
HPL
  Reply


Possibly Related Threads...

Forum Jump:

[-]
10 Latest Posts
How to stay safe while biking?
Yesterday 08:25 PM
Can you help me find out which Koga Miya...
Yesterday 02:42 PM
Chain for specialized rockhopper
Yesterday 01:28 PM
Cold toes during long bike rides
Yesterday 12:40 PM
Singlespeed freewheel chain compability
Yesterday 12:12 PM
How many people ride everyday?
02-28-2021 07:05 PM
Tricycle rear axel removal
02-27-2021 07:52 PM
What kind of frame do I have here?
02-27-2021 03:01 AM
Restoration of a 1980 Falcon Road Bike
02-26-2021 01:39 PM
New bike
02-26-2021 12:52 PM

[-]
Top 5 Posters This Month
no avatar 1. Jesper
12 posts
no avatar 2. Criminal
10 posts
no avatar 3. Painkiller
7 posts
no avatar 4. ILv2MTB
5 posts
no avatar 5. JoJoJo
4 posts