Honda CRF450 Slip-On Exhaust Installation

An exhaust upgrade on a CRF450R is an easy way to punch up performance on a dirt bike that’s already an elite performer on the track or trail. 

Watch the video above and follow the steps below to see how to install a Pro Circuit pipe on a CRF450 Honda dirt bike.

Tools and Parts - Honda CRF450 Aftermarket Exhaust Install

• Basic hand tools
• Spring hook (optional)
• Stainless steel head pipe
• Slip on muffler
• Exhaust header pipe gasket

As part of our complete Honda CRF450 rebuild, we installed three new pieces: a header pipe, a T-4 slip on muffler and a mid-pipe that connects the header and muffler. 

Honda CRF450R Exhaust Installation

Step 1. Remove the two bolts that hold the side plastic panel and the panel itself to get access to all the mounting locations and to position the pipe. 

Step 2. Get the header gasket into position. To keep it in place while mounting the header, apply a little bit of grease to the gasket so it sticks to the head. 

NOTE: Don’t use too much grease, otherwise you’ll burn it all off through the pipes.

Step 3. Get the header and its bolts into place. 

PRO TIP: Only hand-tighten the bolts in case you need to shuffle things around to make the whole exhaust system line up.

Step 4. Position the center section or mid-pipe by sliding over the header pipe and hand-tightening the bolt.

Step 5. Install the muffler by slipping it over the mid-pipe and threading in the bolt that holds it in place. The bolt has two washers: one that goes right behind it, and another that goes between the mount on the slip-on and the mount on the subframe.

Step 6. Torque the two bolts securing the header to the head to 15 foot-pounds. Next, torque the bolts on the mid-pipe and on the slip to 15 foot-pounds. 

Step 7. Hook the two springs near the header, and two springs where the muffler and mid-pipe meet, into place using a spring tool to attach them. 

Step 8. Reinstall the plastics and the bolts that hold them in place.

Step 9. Wipe down the pipes with some contact cleaner to prevent residual oils from your fingers from burning an imprint into the pipes when they get heated.

As mentioned, this exhaust installation is part of a complete CRF450R motorcycle rebuild. Watch the playlist below to see our Honda CRF450 dirt bike rebuild in its entirety.