Honda CX 500 Forum banner
1 - 20 of 23 Posts

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #1 ·
I bought an exhaust off flea bay. I was going to install it yesterday but figured out you have to either separate the mufflers from the 'H' box or drop the brake pedal. I could not get the mufflers off the 'H' box after loosening the collars. I opted to drop the brake pedal. Now it looks like putting the brake pedal back with the exhaust on is a HUGE P.I.T.A.



I dropped the exhaust back off and have spent most of the evening trying to get the mufflers off the 'H' box.

I tried WD-40 yesterday.

I broke 2 strap wrenches trying to get the mufflers to turn.

I put a propane torch on the 'H' box joints and a hammer/chisel on the mufflers.

I managed to tear a couple of holes in the mufflers and I think one moved about 1/4 inch.



If anyone has the phone # for the Incredible Hulk and he can drop by to pull these things apart I would really appreciate the help!



Is there a trick? Am I missing something?

The only option I see is to cut them off and then split the parts left in the 'H' box joints with a hack saw then use a pair of vise grips to extract the pieces.



If that IS my only option anyone got mufflers in good shape they want to sell? Maybe a source for an after market muffler with similar back pressure to stock?



Thanks again for all the help guys!



***EDIT***

Found this on the forum.



http://cx500forum.com/index.php?/topic/999-aftermarket-mufflers/

and

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=17&t=543

and

http://choppercharles.com/cs/forums/64164/ShowPost.aspx



Looks like this subject has been beaten to death.

Sorry for posting on a dead horse.!
 

·
Super Moderator
Joined
·
11,462 Posts
I've never used it, but a lot of the guys/gals here use PB Blaster. Apparently it is a more powerful penetrant than WD40. There are other types too, but I can't recall them off hand. I don't have much else to add, as I've never had to do this job.



Joel in the Couve.
 

·
Registered
Joined
·
1,164 Posts
When I did it I dropped it forward if that makes sense, I took the mufflers off, leaned it forward, and I think I loosened the brakes by the wheel to give the pedal a lot of slack, and wiggled it off and then back on... Can't remember if that's all it took, only did it once and it was early last year
 

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #4 ·
When I did it I dropped it forward if that makes sense, I took the mufflers off, leaned it forward, and I think I loosened the brakes by the wheel to give the pedal a lot of slack, and wiggled it off and then back on... Can't remember if that's all it took, only did it once and it was early last year


Now there is a thought I did not have loosen the brake at the wheel and let the pedal fall forward.

That could make it MUCH easier. Thanks!

I am looking at Harley mufflers on flea bay...
 

·
Registered
1980 Honda CX500C
Joined
·
307 Posts
I wound up slicing the H box, and it was still a bitch. it is pretty hopeless if the H box you have has copious amounts of rust
 

·
Registered
Joined
·
201 Posts
HEAT works wonders. Find someone with a torch. Maybe even pick one up at Harbor Freight.

I fought with mine, trying penetrating oil and force. Heating it with the torch got the H-Box to separate with no sweat in 5 minutes.
 

·
Super Moderator
Joined
·
15,410 Posts
Heat is the best method.



If you want to do the brake lever get a friend.



Have the friend push on the left side where the lever goes through the frame.



Then put the spring on the brake lever and the frame and pull it down hard pressing it onto the splines as your friend holds the other end from pushing out.





I learned the hard way and then learned the right way.
 

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #9 ·
Sounds like it is time to get more serious about the heat. I was using a basic propane plumbing torch to apply heat. Next I will go get the MAPP gas torch I have. Heat that darling up till things get interesting.



Thanks again!



My son wanted to put pirate skulls on the bottom of the 'H' Box. he is 9 and helped me get the rust off it so we could paint it.

Here is a picture:





They did not come out as well as I would have liked but they cannot be seen unless you lie under the bike and look up and he was thrilled.
 

·
Registered
Joined
·
88 Posts
I set the pipes/h box vertical and sprayed WD-40 everyday for about a week and just let it sit. Then I used a rubber mallet to smack them free. Don't be afraid to hit it hard. It took some serious whacking but mine gave just a bit and then I started smacking them the other way. Then I started hitting underneath the curve of the pipe--they both came off.
 

·
Registered
1978 CX500 "The Grub", 1983 GL650I "Nimbus"
Joined
·
11,232 Posts
I separated them with the H-box mounted on the bike. That freed both hands to tug on the muffler. Lots of penetrating oil over a couple days, then lots of propane heat and lots of mallet and muscle.



Only had to have this fight once. Now that they're free, they go on and off easily.





R
 

·
Registered
Joined
·
1,868 Posts
I separated them with the H-box mounted on the bike.  That freed both hands to tug on the muffler.  Lots of penetrating oil over a couple days, then lots of propane heat and lots of mallet and muscle.



Only had to have this fight once.  Now that they're free, they go on and off easily.





R
 What I did as well.  In general, WD40 isn't all that great for freeing up rusted parts.  Something like liquid wrench or pblaster usually works better, there's a few that also have CO2 in them to freeze the part and help it contract and then expand.
 

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #14 ·
Well there was progress tonight.

I sprayed them with PB blaster and went at them with a hammer/chisel.

Well one of them split in half but the thin part is still stuck in the 'H' box.

I will try again tomorrow night. I am thinking I will end up cutting this one into pieces and extracting the pieces.
 

·
Super Moderator
Joined
·
15,410 Posts
Using a reciprocating saw or other slim cutting tool you could cut the inside of the part in the Hbox and then grab it with needle nose pliers and twist them around.
 

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #16 ·
Using a reciprocating saw or other slim cutting tool you could cut the inside of the part in the Hbox and then grab it with needle nose pliers and twist them around.


Stitch,

Yeah that is the plan once they break off. I am going to pound the other one tonight and see if it breaks or if I have to cut it into pieces to be extracted.
 

·
Registered
Joined
·
3,771 Posts
I have never met an exhaust I couldn't get apart and I have never cut it apart nor wrecked it unless it was already rusted very badly. The way to do it is leave it on the bike, or in your case mount it on the bike, gently put a thin wedge of a chisel or screwdriver between the muffler and the tabs of the H-box. Do not bend the tabs more than about 15 degrees out from the muffler. Spray everything with penetrating oil and let it sit and go to lunch or do something else for a while.



When you come back begin pulling and pushing the muffler up and down. When it starts to loosen, start going side to side. When it is is moving in all 4 directions, start to wiggle it and pull at the same time. It will come apart. I find the front headers harder to get out than the mufflers most of the time. With all the exhaust systems I have taken apart I have only broken two insulating collars in the process, which honestly has surprised even me.



I have never destroy a muffler or a an H-box and have only dented one header pipe hitting it repeatedly with a head head hammer. If a header pipe is really hard to get out I have gone so far as to find a tree trunk with a V in it and put the H-box tightly in it a wiggled free the header.



Now ... the whole secret is to take apart your exhaust every two to three years and slobber on anti-seize at the connections. Do this every time you put the exhaust back together and you will find out that it will come apart like a hot knife in butter. It will stink and smoke for about 50 miles after it is re-assembled, but it is a small price to pay to get your exhaust apart easily next time.



If you do this regularly it will take less than an hour to disassemble, anti-seize it and put it back together. That hour is a small price to pay every few years to have something easy to work on.



Maybe those who have had me do this to their bikes will read this and confirm it works well.
 

·
Registered
Joined
·
1,556 Posts
Discussion Starter · #18 ·
Ok they are apart now.

I would like to look forward to never doing that again.

I will be taking Davids advice and disassembling these every couple of years.

Man, hopefully there will be nothing else quite like that!
 

·
Registered
Joined
·
219 Posts
Co2?

I believe the H-box is cast iron.

Cast iron will break or even shatter very easily if it is too cold!

Of course it is the pipe not the H-box that could benefit from temporary shrinking in this case.
 

·
Registered
1978 CX500 "The Grub", 1983 GL650I "Nimbus"
Joined
·
11,232 Posts
1 - 20 of 23 Posts
Top