How to Replace an SRAM Crank and Bottom Bracket


I'm Mike from tree fort bikes. Today we're gonna show you how to remove and install a SRAM crank and external bottom bracket.

To do this work we're going to need a few tools, a 16 notch bottom bracket tool like the part BBT-9 master link pliers we're gonna use for removing our chain and eight-millimeter hex wrench a torque wrench with a high torque setting also with an eight-millimeter hex, a pedal wrench, some grease and a clean rag or two.

To prep the bike for the work there's two things you want to do first we need to remove the chain and we need to remove the peddles.

This chain uses a master link we have a really handy tool to do that call the park MLP. Park MLP is a master link plier, so we're going to locate the quick link here on the chain using the pliers, just fit it around a quick link and we wanna squeeze to open that up so we can remove it, just like so. Then by hand we should be able to wiggle loose the front and back plates of the quick link.

Make sure that the tension on the chain isn't trying to pull it back closed and the chain is removed.

Sometimes these quick links are re-usable but we usually recommend because they're inexpensive go ahead and make sure you put a new one back on when you go to reinstall the chain.

Okay now that the chain is off we also need to remove the pedals. For these I'm gonna use a park pedal wrench. Keep in mind that each side of the pedals has a different thread.

With the right side the drive side paddle it's a traditional right hand thread meaning clockwise to tighten and counterclockwise to loosen the left hand side is the opposite. So the left hand side were gonna go counterclockwise to tighten and clockwise to loosen.

I'm gonna hold the opposite pedal here still and just leverage it until its loosened, and then I can grab it.

Now that we've removed the chain and the pedals we can remove the crank arms. We want to access the non drive side of the bike we have the crank arm fixing bolt located right here.

To remove we need an eight-millimeter hex wrench and we're gonna turn this inner bolt counterclockwise.These bolts are usually installed using a good amount of torque, so it may take some work to get it started. Secure the crank arm like so and loosen the bolt. Now we'll continue loosening until the crank arm is completely removed. Now we can remove the rest of the crank simply by pulling it out on the opposite side. If you want to change your chainrings or if you're replacing the crank, the entire crank itself, this is the way to do it. I've found it's always easier to change out chain rings with the crank arm removed from the bike.

Now we have access to the bottom bracket. If you've noticed any play in your crank arms or the bottom bracket bearings are starting to sound up a bit crunchy or worn you wanna make sure to replace this as well.

To remove an external type bottom bracket whether it be SRAM, Shimano, RaceFace, Truvtiv or FSA, most to those you can use the same tool, which is the park Park BBT-9.

This has the notches to fit onto your external bottom bracket cup. To remove these the non drive side again now these are gonna be reversed from the pedals. This is going to be a right hand thread. We will turn it clockwise to tighten, counterclockwise to loosen.

Take your tool and place it over the bottom bracket and turn until it loosens. Once it's loose you should be able to remove the cup entirely at this point by hand.

Set it aside and we're gonna do the same thing on the opposite side.

Again the threads on the drive side are the reverse. Meaning on that side we're gonna be turning clockwise to loose and counterclockwise to tighten.

Now we've removed both cups from the bottom bracket.
Before we install anything is first make sure that we clean out any dirt, debris or old grease from inside. Use a rag and just wipe out the threads really, really, well.

Make sure you're getting any old grease or tramadol savings or anything out of there so those threads are ready to accept a new bottom bracket.

ok at now-famous prep then we can install a nice new bottom bracket and crank arm.

We're gonna start by taking on new drive side bottom bracket cup.

We can see it already has on this inner sleeve. This just protects the spingle and the bearings from dirt that might be coming in through the seat tube.

Again the drive side is reverse threaded which means we'll be turning it counterclockwise to tighten it make sure that you've greased your threads very thoroughly as well, so that this doesn't get seized inside the frame and you don't run into any issues next time you go to remove it.

Now with the non drive side, this one is right hand threaded, we'll turn it right. Now take the bottom bracket tool.

We're gonna tighten the cup, the torque specs on this is 25 to 35 ft/lbs if you don't have a torque wrench that's just basic can be good firm tight just about like so.

Now we're going to take our crank arm, we wanna lightly greased the spindle and slide it back onto the bottom bracket. One thing to lookout for with the SRAM is that has this outside seal, that's going to tend to wanna pop off when you push the crank arm back through, so hold it in place and make sure they are lining up the splines on the spindle with the matching splines on the inside seal and push it through.

Now we're going to take our non drive side crank arm, make sure that we're installing it directly opposite to the drive side and grab the eight-millimeter hex wrench and tighten it.

With SRAM cranks the torque specs on this bolt are pretty heavy and is printed right there this one is going to be 425 to 478 InchLbs, which is quite a bit. This is an instance where it's very handy to have a torque wrench. We're going to use ours fitted with an eight-millimeter hex bit. Make sure we get our torque specs on there. We're gonna torque the bolt to the recommended specifications, which is quite a bit. Now we're finished, at this point we just need to reinstall the chain and the pedals and we're ready to ride.

So that was the removal and installation of a SRAM crank and external bottom bracket, as you can see it's pretty easy to do thanks a lot for watching.