Topic: Help! with Used 4-4 exhaust

[Rain City Rider]

I bought a used set of 4-4 pipes for my 78 cb 750 and I just got them today. There seemes to be a lot of rust and corosion in them. Is it possible to get them refurbished? Or is that just the way they are? Does anyone have any tips or advice. I spent a good pennie on them and would like to use them. But I don't want them to sound like krap.

[Bob Wessner]

Are there areas where it has rusted through, or are you talking about surface rust only? I had to clean up mine, one pipe (#1) was hopeless and replaced. the other three were surface rust. I used fine steel wool and WB-40 as a lubricant and most of it cleaned right up. If there are pits, but not rust through, the best you can hope for is reducing the apparent size, pits are pits. If by refurbishing you mean re-chroming, that could be expensive and the outcome pretty much dependant on the quality of the pipes to begin with.

[Rain City Rider]

There are some small holes but the outside looks good. There seems to be a lot of stuff rolling around inside though. Do I just have to deal with The rattle?

[Bob Wessner]

There seems to be a lot of stuff rolling around inside though.

I had a few of those (internal rust pieces) in mine as well after 22 years of storage. I just removed them and tapped them a few times and worked the loose pieces out the header end.

[Rain City Rider]

The cones on the ends are loose on a couple of the pipes and there is a lot of dust and pieces coming out of one. Should I rip out the little cone pieces so they don't rattle?

I have used some stuff called Quick Brite in the past to polish chrome, it works well.

[Bob Wessner]

The cones on the ends are loose on a couple of the pipes and there is a lot of dust and pieces coming out of one. Should I rip out the little cone pieces so they don't rattle?

Are you talking about the baffles at the rear of the pipes? These were/are removeable on earlier stock pipes, but not sure they are removeable on later ones. If these are removed, they will alter the performance/back pressure I would think.

[Rain City Rider]

Here are Pics

[eurban]

The 77/78 style pipes do not have removeable baffles and there is no way to get inside them without cutting them up.  The pieces that you hear rattling around in them may be a good bit more than rust bits.  I have seen a couple sets of these pipes with much of  internal baffling loose inside even though they look relatively nice on the outside.  The rusted out ends are most certainly going to effect sound  and will likely effect performance, particularly since in all likelyhood the pipes have different amounts of loose pieces and different shapes and sizes of holes.  Sorry to hear that you paid a pretty penny for them as refurbishing would be difficult.   Seems a bit  like you got ripped off .  Can you get your money back?  One option that I considered for my 78 (until a managed to piece together a NOS set) was to cut all the ends off, clear out the loose internals and install some sort of baffling system.  The ends could then be welded back. Obviously some sort of refinishing of the ends would be inorder . . paint etc.   I even thought about mounting a Supertrapp muffler core into each pipe and using their discs and endcaps for cool looks and tuneable sound.  All of these ideas might be feasable but would take a good bit of work and some additional $.  Hope this helps

[rt]

Hiya,

had something similar with my used 500 4in4 set. Two silencers were 'welded' (as in horribly tacked together by somebody who's surely not knowing what he's doing), the rhs upper silencer had a serious rattling noise when shaken, so I first decided to try and poke the stuff out through the rear hole with a welding rod. As this brave attempt failed I went for Plan B - cut a 3 by 2.5" window into the silencer (wheelside, where it's hardly seen anyway when bolted on), removed all loose stuff (see pic for the bigger parts) and closed that with a stainless steel patch and a proper weld. As yet I didn't realize any change in performance. I think she's even doing better, as I believe the previous owner didn't alter carb jetting when he put a Motad 4in1 on, so now she's back to (nearly) stock. I might as well be wrong there....  One obvious difference is a more 'fruity' sound note though (not too loud I hasten to add  ).   
The overall difference to your assembly seems to be that the system I bought off eBay was cheap and precisely described by the seller (I even got detailed pics of dents, corrosion,...), so I knew what I was getting beforehand...

From what I see in the pics I would agree to Eurban; if you really paid loadsa dosh for that set it seems you have been ripped off. I assume, if you try and poke around those corroded areas you'll find more horrors lurking underneath. Try and get your money back!

Success...

[Rain City Rider]

So I figure I bought them I should put them on. Right? They actually sound OK, kind of poppy, and the bike runs better. I don't have to let it warm up as much and it doesn't bog down at mid to high rpm's anymore, a result of changing the exhaust and not rejetting the carbs I have been told. So I would say not the best ending but not a horror story either. Thanks for the help and your suggestions.
[img=http://img253.imageshack.us/img253/8751/newpipes6za.jpg]

[Rain City Rider]