Tip & How-To about Exercise & Fitness

How to Remove and Replace the Bottom Bracket on an Indoor Cycling Bike

Following is a basic guideline of removing and replacing the bottom bracket on an indoor cycling bike. Due to the different brands of indoor cycling bikes and designs for bottom brackets, the following should only be used as a guideline. If any of the information is not exact to the bike being serviced, refer to the service manual or call Sportsmith for further help.
Common Tools Needed:
Phillips Screw Driver
Set of Allen Wrenches (standard and metric)
Bottom Bracket Tool
Cotterless Crank Puller Tool
9/16" Socket
Ratchet Wrench
Pedal Wrench
Crescent Wrench
You will begin by removing the outside belt/chain guard by using either or both the Phillips screw driver and Allen wrenches. It may be necessary to remove the drive side pedal (using the pedal wrench) in order to completely remove the outside belt/chain guard.
Once the belt/chain guard is removed, you will need to remove the belt/chain. If the unit is belt driven, you can simply "walk" the belt off the pulley by pushing the belt to the outside while turning the crank backwards. **CAUTION: PINCH POINT ** If the unit is chain driven, most use a continuous chain that can be "walked" off the sprocket just like the belt. **CAUTION: PINCH POINT ** Some chains may use a connecting link and can be separated at the connecting link to remove the chain. The connecting link is different in appearance from all other chain links.
Now it is time to remove the crank arms. How to Use a Cotterless Crank Puller Tool
It works best to place the bike upside down for best leverage to remove the bottom bracket. (If placing the bike upside down, ensure proper seat adjustment for best bike balance.) Begin removing the bottom bracket from the drive side of the bike. This side has a reverse thread. You will need to turn right to loosen and remove the bottom bracket. Place the teeth of the bottom bracket tool into the teeth of the bottom bracket cup. Using the ratchet wrench or crescent wrench to turn the bottom bracket tool, you will turn right to loosen and remove the bottom bracket. (If removal of the bottom bracket is difficult, it helps to use a crescent wrench in combination with a bolt threaded into the bottom bracket shaft to hold the tool in place while applying pressure to break the bottom bracket loose.) Remove the bottom bracket from the frame. Remove the bottom bracket cup and/or lock ring from the non-drive side of the bike. This is a standard thread. You will turn left to loosen and remove this bottom bracket cup and/or lock ring.
Install the new bottom bracket from the drive side and tighten flush to the frame. Install the bottom bracket cup and/or lock ring to the non-drive side and tighten.
Re-install the crank arms and pedals. Make sure the crank arm bolts are tightened to the proper torque. If unsure of proper torque specs, refer to the equipment service manual or call Sportsmith.
Re-install the belt/chain onto the pulley/sprocket. If belt/chain was "walked" off the pulley for removal, it can be "walked" onto the pulley/sprocket by placing the belt or chain along the bottom of the pulley/sprocket. Carefully, turn the crank arm forward while lifting on the belt/chain. **CAUTION: PINCH POINT ** Continuing turning the crank forward until the belt/chain is in place.
Re-install the outside chain guard and test the unit. Ride the bike without tension and test with tension. Ensure functionality and feel of the ride. Make any adjustments if necessary


Removing and Replacing Bottom Bracket on Indoor Cycling Bike

Posted by on

Exercise & Fitness Logo

Related Topics:

Related Questions:

1 Answer

crank set replacement. Trying to replace the crankset due to a stripped crank arm. What crank is compadible to replace it with?


The only guarantee for an exact match width-wise is to use the same make and model of the crank you're replacing. A change in the given bottom bracket and crankset pairing will almost always yield some difference. Bike shops seem to have a way of determining a starting point for it but my own experience with them is that trial and error plays into it. If you change crank brands you may have to also change the length of the BB to get the same effective pedal dimensions.


http://www.parktool.com/blog/repair-help/categories/bottom-brackets

http://www.parktool.com/blog/repair-help/categories/crank-service

Sep 15, 2011 | Gary Fisher PreCaliber 24

1 Answer

Getting a clicking sound from the bottom bracket area. I have a Denali Pro. Can I replace the bottom bracket and what size


Yes, of course you can replace the bottom bracket.

First though you will want to make sure that the clicking noise is in-fact coming from the bottom bracket. Even though it sounds like it is coming from that area there are other things that can cause a clicking noise, such as the examples below.

Front derailleur cable end hitting the crank-arm is a common clicking noise.
Pedals can also cause a clicking noise that sounds like its the bottom bracket.
chain rubbing the front derailleur
chain has a kink in it.

The size of your bottom bracket is related to a few factors:
1 - thread pitch (your bike is english)
2 - Bottom bracket width (your bike is 68)
3 - Crank style and brand. This I do not know for your particular bike as you did not provide the year of the bicycle or brand of crank, and they change.

Taking off cranks and removing and installing a bottom bracket requires many bike specialty tools and is probably not the best project if you have never done this before or own the tools. It will be far less expensive to have your local bike shop replace the Bottom Bracket then to do it yourself. Plus they can tell you what size it needs and if the click is even coming from that part or not.

Dec 10, 2010 | Cycling

Not finding what you are looking for?

474 people viewed this tip

Ask a Question

Usually answered in minutes!

Top Exercise & Fitness Experts

Electro Med Services...
Electro Med Services...

Level 3 Expert

6694 Answers

Howard
Howard

Level 2 Expert

115 Answers

Tom Chichester

Level 3 Expert

34765 Answers

Are you an Exercise and Fitnes Expert? Answer questions, earn points and help others

Answer questions

Loading...