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Need advice for installing replacement exhaust ('95 model)

peterke

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I got an un-modified pair of exhausts for the '95 NH. The ones I had on them had their mufflers removed by the original owner, and they were too loud for my liking...
So, I'm not a mechanic, but I got my hands dirty on cars and motorcycles many years ago, so I decided to do the replacement myself.

I got the old set off. The first thing I noticed was that there were no gaskets at the end of the pipes where they attach to the engine block. Weird. Thanks god I got bought a new set before even starting to work on this.

But I'm having the hardest time putting the replacement exhaust back on...

Is this supposed to be able to be done by one person??? I can't seem to fit the thing on, align it in the right place at all mounting points, hold it, and put the screws in... Or is there a specific sequence to do this?

If anyone could advice on this, that would be good. Otherwise, I have to call a few friends over :))
 
Did you loosen the crossover pipe connection so that the two halves can move somewhat independently of each other?

I only know your supposed to get everything in place "loosely" mounted first then tighten the header to the head 1st, then the rest.

Honda is famous for it's "this part only fits this one bike" manufacturing methods. If you mean the pipes just don't line up and you need to force one 1/4" to the left then yeah, clamps, spreaders, friends with strong hands, may be required.
 
Yes, I have the crossover pipe lose. It doesn't seem like there is a problem with fitting the 4 headers correctly to the engine. It's more like I can't seem to do it all by myself. I'll give it another go. Per the manual, you supposed to remove the brake-pedal. But I don't know how would that help...
 
Ah, I understand now.

I'd probably start with 2 bolts in the front. 1 each on pipe 1 and pipe 4, just to hold it up close to where it goes. Use 2 extra long bolts so you can screw them in deeply, but not tightly, to prevent accidentally pulling out the threads. Then get something connected near the back and continue working back and forth at little here, a little there.
 
Good idea. I also hired one of my friends just in case ;)

One last thing (hopefully): when I pulled off the old exhaust, I found no gaskets. I tried to see if they somehow became one with the engine block. But it doesn't seem like it. From what I can see, there is nothing there. Mind you, this is the first time in my life I do such work, so I'm not experienced.
So is it even possible to have no gaskets and no "leak"?
And should I just put the new gaskets in, no matter whether there are old gaskets there or not?
 
Use gaskets, the other person didn't. The most common cause of popping or pipe backfire during deceleration is a leak there. If the leak big enough it can even damage valves.

It's not your fault other people are stupid.
 
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Wow. I had popping non-stop during decceleration. I had no idea why! Thanks for the tip. I'll definitely put the new ones on.
 
Now you know why...........And if the carbs have some sort of air control for decel that can do it too. That one may have air injection into the exhaust that can leak or if defeated incorrectly cause the same issues.
 
Thanks for all that.
We gave it a go with my friend last night. We attempted to losely put up the whole thing and then secure, but didn't work. The mounts at the rear don't line up with the screw-holes. The whole exhaust on both side is a bit too much forward. About 5-7mm on both left and right side. No matter which way we jiggled and jerked it.
Then we tighthened the mounting screws at the front, where the headpipes attach to the engine block (with the gaskets in place), and we gained about 1-2mm, but it's still not enough to line up the holes.
Also, in the middle, underneath the engine, seems to have the same issue: the exhaust is too much to the front, and needs to somehow slide backwards about 3-4-5mm before the screw fits in.
We ended at that point as it was getting late evening but we agreed on 2 possible course of action:

a) start from scratch. Maybe the headpipes just don't line up exactly with the holes on the front of the engine. So we will take the whole thing off, and try putting them on again. And will be more careful about aligning the headpipes and maybe somehow we can gain back that few mm-s we are missing.

b) if that doesn't work, and we are still missing a few mm, we are going the enlarge the back mounting holes on the exhaust on both sides with a drill, so we can stick through the screw and secure it like that. And we just skip the middle mounting screws under the engine...
 
This is now done. New pipes in place. Had to enlarge the back mounting hole a little to make it fit, and the middle screws under the engine were skipped...

New gaskets in place, and she sounds great!!!

Thanks for all the input.
 
This new exhaust REALLY made a difference. The sound is really good, and also the popping during decceleration is completely gone. Really happy with the result
 
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