Installing Cobra Classic Deluxe Slashcuts P/N 1573CS

by "Gearhead"

notes and images by Tom "911Medic1" Myhre

Removing the Stock Exhaust

1. Lay out some towels or rags along the length of the bike so you have some place to set the stock exhaust and the new pipes where they won't get scratched. You might want to also have a place picked out to set your stock pipes when you are finished with them.
   
   
2. Remove the right side cover to make easier access to the rear exhaust header nuts.
   
   
3. Remove the front and rear exhaust pipe heat shields to make easier access to the exhaust header nuts. After loosening and removing the three bolts that hold on each heat shield, you can pull them off. They may feel like they won't budge but they will with some muscle and patience. I used a pair of gloves to save my fingers. For each shield and starting toward the rear of the bike, I curled a finger around the tab that the bolt went in [pic] and with my other hand on the back edge of the heat shield I pulled on the tab and shield. Work back and forth between the tabs and eventually pry the shield off. [pic]
   The stock heat shields are VERY tightly attached. I actually thought I might tip my bike over trying to pry them off. The tabs pictured here did bend when removing my shields. I was able to bend them back into place easily, however. I gained a whole new respect for Honda build quality once I got these shields off. They are very well-made.
   
   
4. Loosen and remove the front and rear exhaust header nuts using a 12mm socket, one or two socket extensions, and/or a 12mm wrench. I noticed on my rear cylinder the lower header nut had been bottomed out on the stud, and the top nut only had about a ¼ turn before it bottomed out.
   
   
5. After the header nuts are off, slide the flanges and the front heat shield vibration isolation mount down the headers to their lowest point so they don't fall down when you remove the exhaust system.
   
   
6. At this time the exhaust assembly is only held on your bike by the frame bracket and its bolts located under the front cylinder muffler.
   
   
7. Loosen and remove the 12mm nuts on the bolts at the mounting bracket below the front cylinder muffler but do not pull the bolts out.
   
   
8. Firmly grab the rear of the exhaust pipe assembly and the front pipe and pull the assembly away from bike. The bracket bolts will come away with it.
   
   
9. Set the exhaust assembly on the towels in front of the bike. You may want to remount the heat shields.
   
   
10. Remove the bolts from the bracket because you'll need them and the nuts to mount the new exhaust bracket. Move the stock exhaust pipes to another location to get them out of your way while you mount the new exhaust system.
    
    
11. Get a pick or a small screwdriver to remove the crush gaskets from the cylinder exhaust ports. If you dig at the gasket outer diameter and pry toward the inner diameter, you should fold up a piece of the gasket that you can grab with some pliers and then jerk the gasket out. Don't gouge the sides or bottom of the ports as you pry on the gasket.
    
    
12. Wipe the ports clean, go get your new gaskets, and install them in the cylinder exhaust ports now so you don't forget to do it. Install them in with the seam facing you (away from the bike). Push lightly around each gasket until it seats at the bottom of the cylinder exhaust port.
    Others that have added aftermarket pipes (regardless of brand) have heard that the seam is supposed to face AWAY from the header pipe and TOWARD the exhaust manifold. All the Honda service manual says is 'Make sure that the new gaskets are installed in position.' I don't know how critical this is, or if it matters at all. If you wish, investigate further before switching pipes.

Installing the Cobra Exhaust

I tried to follow the cobra instruction and although they're pretty good, things just didn't line up without having to force it. The following are the steps I took which worked very well for me.

1. Pick the muffler you want to be at the top on the bike (rear muffler) and place one of slider brackets in the keeper on the muffler with its flat side facing away from the muffler. [pic] Mount that muffler to the muffler bracket in the "rear cylinder muffler mounting hole" location. [pic] Use the screws supplied with the kit but only snug them down so the muffler can slide back and forth on the muffler bracket.
   
   
   
   
2. Slide a muffler clamp over the end of the muffler so that the tightening screw will be aimed up toward the seat when you mount the bracket.
   
   
3. Set the muffler bracket and muffler to the side for a minute.
   
   
4. Slide one of the exhaust flanges up onto the rear header pipe and place the port end of the pipe in the rear exhaust port. Slide the flange over the studs and place a washer on each stud. The washers are because the stock flange is a little thicker than the Cobra flanges. On my 2002 Sabre, the rear exhaust header nuts were nearly bottomed out on the studs with the stock exhaust. Alternating between nuts, tighten the header nuts until the header pipe is snug with just a very minor wiggle. Rotate the end of the pipe so that the straight section running to the rear of the bike looks parallel to the ground. With the nuts snug, the header pipe should just about support itself when you let go of it.
   I was able to buy some solid Aluminum washers at Home Depot that I used for this purpose. I won't ever have to worry about rust. The diameter is a little bigger than necessary, but you don't really notice them after the install is complete anyway. I was a little concerned that they might be too soft to hold up, but after torquing down the bolts, they held up just fine.
   
   
5. NOW FOR THE FUN PART! Pick up the muffler bracket and muffler, and slide the muffler onto the rear header pipe while also supporting the rear header pipe. As you slide the header into the muffler, take care not to cause excessive torque on the rear pipe that might crush the gasket in the exhaust port. As you slide the header into the muffler, visually watch and allow the part of the muffler bracket that mounts to the frame slide behind the frame mount (the opposite side that the stock exhaust was mounted). [see blue arrow in pic] Once the header has been inserted into the muffler to the appropriate depth, slip one bolt through the frame mount and muffler bracket. It may take a little jostling to get the muffler bracket holes to align with the frame mount holes. Once you jostle the alignment, put the other bolt in. You may have to force the bolt with a thumb but you should not have to hammer it in.
   I initially followed these instructions and mounted my bracket BEHIND the frame mount. It mounted there easily, and the pipes looked great. However, once I was finished, I noticed that there was very little clearance between the swingarm and the end of the tube steel bracket (see blue arrow in pic). There was MAYBE 1/4" of clearance. So, being concerned that during riding there might be contact, I bought some new crush gaskets and began mounting them again, with the bracket in FRONT of the frame mount. (You DO have to completely disassemble the pipes to do this, by the way; things just don't line up right if you don't, even though you're only rotating the pipes about an inch or two.) I discovered while doing this that two things happened: 1) The bracket and frame mount don't match up. It appears that the bracket was made to go behind the frame mount. When brought in front, the surface of the bracket and the surface of the mount don't lie flush against each other. You can still get the bolts through the holes, and I'm sure you could get things to line up with the torque applied when tightening down the hardware, but I didn't like the idea of doing it this way. 2) The front header pipe moved away from the bike ~2 inches. It began to infringe on the right peg. I have heard this complaint from other owners of these pipes, and think that maybe this is the cause. So, after seeing these effects, I elected to have the bracket mounted on the inside of the frame mount, and just monitor the swingarm/bracket for any contact. I bought my pipes used, and didn't have Cobra's instructions, so I can't comment on how they say to do it.
   
   
6. Tighten the muffler bracket to the frame mount using the stock nuts and the bolts you just inserted. This will bring the muffler and muffler bracket in line with side of the bike.
   I was able to properly torque these bolts down, but had to place an adjustable wrench on the nut and allow it to rotate around until it braced itself against part of the frame mount. You can see the wrench behind the frame mount in the pic.
   
   
7. Place a slider bracket in the keeper on the other muffler with the flat side facing away from the muffler. Hold the muffler up to the muffler bracket aligned with the "front cylinder muffler mounting hole" location. Reaching from underneath and behind the frame mount insert the bolts through the muffler bracket and into the muffler slider bracket. Snug these bolts just like you did the rear muffler.
   
   
8. Slide a muffler clamp on the front muffler so that the tightening screw is aimed toward the ground.
   
   
9. Slide the other exhaust flange onto the front header pipe.
   
   
10. Slip the front header pipe into the front muffler and then rotate the header toward the bike so that the port end mounts cleanly in the front cylinder exhaust port. You may have to slide the header into or out of the muffler to get the port end to line up good with the port in the cylinder. Slip the flange onto the studs, place a washer on each stud, and then alternately finger tighten the exhaust header nuts. I put washers here just to match the rear.
    You can see the oversized Aluminum washers I used in this pic (blue arrows).
    
    
11. Step back and look at the set-up to make sure it is to your liking. Mufflers should be parallel with about 1/8" - ¼" space between them. Jostle it around to slide stuff back and forth if you want. However, the rear muffler and rear header pipe probably won't move very freely at this point. If you move stuff around, try not to put load into the exhaust gaskets.
    
    
12. Wipe off the header pipes to remove all smudges and fingerprints, and try to keep them clean while installing heat shields.
    
    
13. Feed the hose clamps into the tabs in the front and rear heat shields. There are two in each heat shield. I put mine in so that the tightening screw would be aimed toward the ground on the rear part of the pipes and aimed toward the front of the bike on the upper part of the pipes when the shields were installed.
    
    
14. Spread the clamps out as you place the front and rear heat shields onto the front and rear header pipes. With the shields on, re-feed the hose clamp belt back into the screw on the hose clamp so you can tighten them. Tighten them up but leave them loose for now. Make sure the heat shields are positioned to cover the welds on the mufflers. On mine, the front was overlapped well, but the rear just barely overlapped the weld.
    
    
15. Now that everything is mounted to your satisfaction, it is just a matter of tightening everything up. At this point the muffler bracket should already be tight to the bike. If you need to loosen it and re-tighten then do so. I would make sure this bracket is tight before tightening anything else because as this bracket is loosened, the mufflers and bracket will begin to cant away from the bike. The bracket keeps the mufflers pulled in line with the side of the bike.
    
    
16. Begin by tightening the exhaust header nuts on the front and rear headers. Alternate between the top and bottom nuts turning the same amount by hand until snug, and then with a wrench until tightened to the proper torque.
    17 lb-ft/23 N-M, per the Honda service manual--for the stockers
    
    
17. Next tighten the bolts holding the mufflers to the muffler bracket.
    
    
18. Next tighten the muffler clamps. Position the clamps about mid-way over the slots in the muffler to get a good squeeze onto the header pipes.
    I tightened these to 20 N-M/14 lb-ft. This is the torque called for to tighten the stock clamps. However, the stock clamps have a replaceable gasket between the clamp and header pipe, and the Cobras don't. I did it anyway, and didn't feel it was excessively tight.
    
    
19. Last, tighten down the heat shield hose clamps.
    
    
20. Wipe the entire assembly as best you can to remove all finger prints, oily smudges etc. These might otherwise discolor the pipes when you fire it up and they get hot.
    
21. Now your reward! Fire up the bike with your normal starting procedures. You might want to use earplugs just in case it backfires. It should crank up and idle strong with little or no choke. If you hear any sputtering, snapping, popping, or backfires you may need to adjust the mixture screws. If it stutters, rides jerky at low RPM acceleration or backfires on deceleration you may need to adjust the mixture screws. My screws had previously been adjusted (front 3 ½x and rear 3 3/8x) during a carburetor adjustment by the dealer. When I fired up the bike, I used choke and then immediately turned it off. The bike idled strong and smooth. I let the bike idle for about 2 minutes and jumped on it for a ride. During the ride, the bike ran smooth, pulled hard, and did not backfire at all on acceleration or deceleration.