Words by: Max Morgan
After clocking in miles and miles over the course of a season, your bike can certainly take a beating. Not too many riders ride as hard as Yeti Cycles ambassador Adam Morse. Adam is an Enduro World Series competitor and for years has been a staple for mountain bike racing in the northeast United States. After a full season of riding in New England, bikes get covered in mud from head to toe too many times to count. Adam's race bike of choice, the Yeti SB150, is no different. Even if tearing down each and every component on your bike only happens once or twice a year, this kind of routine maintenance will keep your bike running smoother and will certainly extend its life.
For those looking to freshen up their bike, we've put together a step by step walkthrough going over the ins and outs of Yeti's Switch Infinity suspension platform. Today we are tearing down a Yeti SB150 frame, checking over each of its components, and reassembling the Switch Infinity suspension system like new! Aside from the SB100, all of Yeti's other current mountain bikes share an almost identical suspension configuration (SB130, SB140, SB150, and SB165). The layout on the SB100 frame is, of course, a Switch Infinity design but is optimized for the overall lightweight and tightly packaged 100mm travel ripper.
Adam Morse charging on his Yeti SB150 - Photo by Brooks Curran
Now before we get started, it's always best to start with a clean bike! Give your bike a proper wash before we started disassembling the suspension system.
For starters, we will need a good set of hex keys, including a 10mm hex key. It's not all that often you use a 10mm, but on the SB150 we will use the 10mm on the main pivot bolt. We will also need a 3-way hex wrench for each of the fasteners that require a hex wrench on either side. We will also be using Maxima Waterproof Grease, a Park Tool UP-1 pick, Simple Green cleaner, shop towels, and a Yeti Switch Infinity grease gun.
Before we get into disassembling the frame, we will first remove the cranks and chain guide from the bike. This will allow us to access all of the frame hardware without constantly fighting with the crankset and chainring. It is also a good idea to remove the rear wheel from the bike, that way you won't be supporting the weight of the wheel, cassette, and rotor when removing different suspension components.
Let's get into it! First, start by removing your shock. On the SB150, the rear shock bolt uses a cone washer to keep the rear shock bolt from backing itself out. Using a 4mm hex key, remove the bolt and cone washer. Now using a 5mm hex key, remove the rear shock bolt. The front shock bolt is a bit more traditional and can be removed with a pair of 5mm hex keys, one on each side.
With the shock removed, this will be your first chance to cycle the suspension by hand to feel either how smooth or rough the bike is running. Before disassembling any of the frame components, it is helpful to take a mental picture of how the frame is assembled.
Because it will be easier to not remove the shifter cable and brake cable that is internally routed through the frame, it is best to work on the upper linkage system and lower Switch Infinity individually. Start by removing the upper linkage system. Using a 6mm hex key, remove the frame bolts on each side shown in the photo below. Applying pressure to the keyed hardware will keep them from backing out and spinning while you use the 6mm. Remove this hardware from each side and set it on your workbench for now.
Now using a 6mm hex key on each side, remove the axle that secures the upper linkage assembly to the front triangle. Be sure to have a firm grip on each of your tools here. Remove the axle and axle bolt and set them on your workbench for now.
Now that all of the different hardware that holds the upper linkage in place has been removed, simply slide the linkage and all of its parts out of the frame. Remember, we just washed this bike and look at how this particular linkage is still covered in dirt and grime! This is the kind of grime that builds up over time and can cause premature wear on all of these components.
This is a chance to clean each of the different components in the upper linkage but also a good time to do a visual inspection. First using a 5mm hex key, remove the hardware that holds the "shock extender" in place. You will find an aluminum washer on each side of the shock extender. Wipe clean all of the parts that make up the upper linkage, including the hardware removed from step 3, with some Simple Green and shop towels. Once everything is clean, check by hand to see that each of the different bearings on the linkage and on the frame is running smoothly. Because the bearings on Adam's bike are running smoothly, we are going to continue running them. If any of your bearings need to be replaced, give us a call at the shop to get a hold of a bearing kit for your specific Yeti frame.
Now it's time to reinstall the shock extender. Be sure that the orientation of the shock extenders themselves and the washers used is correct and matches the photos below. Torque the hardware that holds the shock extender in place to 10 Nm.
Before the upper linkage goes back into the frame, make sure to clean the frame and each of the bearing seals with some Simple Green and shop rags. Using the Park Tool UP-1 pick is helpful when trying to get every last bit of the dirt and grime out from each bearing seat.
Apply a thin layer of Maxima Grease to the upper linkage axle and slide it through the frame. Using a 6mm, torque the linkage pivot male bolt to 15 Nm. Next, slide the linkage into the seatstay. Again, use a thin layer of grease on both the keyed male seatstay linkage bolt and the female seatstay linkage bolt. First slide the female seatstay bolt into place, followed by the keyed bolt (male). Torque the female seatstay bolt to 16Nm.
Now it's time to get to the Switch Infinity and the main pivot bolt. First, remove the wedge bolt using a 5mm hex key. This allows you to get to the main pivot bolt using a 10mm hex key. Remove the main pivot bolt and the collet nut found on the drive side.
Next, using a 5mm hex key, remove each of the four bolts holding the Switch Infinity in place. Swing the rear triangle out of the way and slide the Switch Infinity out from the frame. Be careful not to lose any of the black spacers that fit into the Switch Infinity.
Be sure to clean the Switch Infinity as best as possible. Yeti recommends leaving tearing down the Switch Infinity itself to the professionals. You should be able to wipe clean any dirt and grime from both the Switch and the frame. Being so close to the ground, it's easy for this same kind of nasty dirt and grime to buildup in these nooks and crannies on the frame.
Now that both the Switch Infinity and the frame are cleaned, it's time to reinstall the Switch back into the frame. Before sliding the Switch Infinity back into the frame, a good trick is to apply a thin layer of grease to each of the four black spacers so they want to stick in to place. It is very easy to have these flying all over the floor so be careful. Using a 5mm hex key, torque the four Switch Infinity bolts in a cross pattern to 12 Nm.
Apply a thin layer of Maxima grease to the main pivot axle and using a 10mm hex key, torque the axle until there is no play in the system (roughly 12 Nm). Next torque the wedge collet (cone washer) to 14 Nm. This wedge collet helps prevent the main pivot axle from backing out.
With the suspension components back in place, it's now time to reinstall the shock. Start by sliding the rear shock eyelet in between the shock extenders and torque the rear shock bolt to 13 Nm. This collet axle should come through the bottom shock extender and thread into the top shock extender. Finally, install the front shock hardware and torque the male bolt down to 10 Nm.
With the shock installed, bring out your Yeti grease gun (needle type grease gun) and pump grease until you see grease starting to come out of the shaft seals. Wipe away any excess grease and you are ready to go!
We are almost there! The frame is all together and now all that is left is to install your chain guide, crankset, and chain! Make sure to have all of the drivetrain buttoned up and the wheel installed correctly before riding. For more info and technical step by step tutorials, check out our full collection of How To articles. Thanks for following along and enjoy riding your bike!
Now go out and ride your Yeti like Adam - Photo by Brooks Curran
This article was written / authored by Max Morgan. Max has been a professional downhill mountain bike racer for the last 10 years, competing in the UCI World Cup downhill series and U.S. Pro GRT series. Having ridden all different kinds of bikes on trails all over the world, Max's experiences being out on the circuit give him a unique perspective on what makes for a quality cycling component. Max also has degrees in Mechanical Engineering and Physics, and so if you don't see out on the trail, chances are he is probably in the garage tinkering on the next project.