The Great & Terrible Ask "which exhaust headers not made for the 650G fit the 650G"
My bike [1981 650G] is loud. Extremely loud. My friend tells me that when I meet her at the archery range, she can hear me coming two full minutes before I show up. In the middle of the woods. I short-shift into 3rd if I pass schools or playgrounds on city streets to avoid destroying children's eardrums. I gently accelerated in front of a van full of nuns and the driver (a nun) crossed herself with great haste. I am legally barred from riding within 100 yards of pregnant women. Only the last item on this list is at all falsified.
I have already replaced the exhaust gaskets and "connectors" (the fibrous tube gaskets on the 4-2 collector) and while that improved things a little (i.e. there *was* some leaking), it's still about as bad as it ever was. Whatever wonderful magic baffles were inside the mufflers seem to have long since rotted away, and Suzuki - in the heady caution of the early-smog days - saw fit to weld the mufflers right to the pipes.
And even if they hadn't, I'm sure that the 45 years of rust and corrosion on the pipes will eventually come to roost. I'm also sure that all the flow caused by the loss of baffling is not doing the stock jetting any favors.
So I'm looking for exhaust parts. Not urgently - I've got a lot of backlog on the bike - but looking nonetheless. I suspect even the most nominally baffled look-at-me megaphone would be an improvement on my current situation.
A first instinct might be to get some stock pipes cheap from ebay and cut them off at the muffler. I am ruling this a non-starter, as the stock pipes are double-walled (and the inner wall is quite thin). I don't think I'd be able to make a clean cut through both walls without collapsing the inner one and causing all sorts of issues with flow. A quick look on eBay turned up some listings where people have tried just that, and every single one of them that has an end-on picture has a warped and useless inner pipe showing, so I feel validated throwing this approach out.
Nobody makes aftermarket headers or systems for the 650G. MAC made a 4-1 rumored to be of dubious quality - these rumors must remain such, as it's totally out of stock everywhere, and MAC is dead. Delkevic makes 4-1 systems for almost every other Suzuki of this era, but not the 650, as do a couple other companies.
And to be honest, I don't really want a 4-1. I especially don't want a 4-1 at the cost of my centerstand. What I would like to do is find some headers that fit the exhaust ports and clear the block, then select, construct, or commission 4-2 collectors that slip past all the stock equipment on the bike, then finally select and install some off-the-shelf mufflers that are not so unholy as to require direct ecclesiastical intervention. I could skip all this and commission some headers, but that costs a signficant amount money (vs repurposing) I'd rather save for other things.
It would be irritating (but certainly possible) to kitbash the headers from a 4-1 into something that would feed into a 4-2. Even the first few inches fitting would simplify (and cheapen) construction a lot.
So my big question is: what, if any, other Suzuki fours have exhaust HEADERS that can be fitted to my bike?
I have heard many rumors that headers for the 550 of the same year is compatible.... almost. The exact definition of "almost" is variable according to source. Some people (on the internet) say the 650 ports are slightly too big for it to work, some other people say they're slightly too big but adding an add'l crush gasket makes them fit - other people say the ports are too big AND the bolt pattern is wrong. Some people say that the down pipes are too short to clear the block. Some people (my favorite people) say that the headers fit exactly, it's just that the collectors and muffler mounts downstream don't - which would be perfect.
I think the 550 pipes are slightly slimmer than the 650 pipes - but if the port fits, then I'm not concerned, as aftermarket pipes are singlewall and therefore will probably have a comparable ID to stock 650.
I vaguely recollect - can't remember from where, possibly a wishful daydream or feverish vision - that the 1983? 750ES? headers are partially compatible too.
My bike [1981 650G] is loud. Extremely loud. My friend tells me that when I meet her at the archery range, she can hear me coming two full minutes before I show up. In the middle of the woods. I short-shift into 3rd if I pass schools or playgrounds on city streets to avoid destroying children's eardrums. I gently accelerated in front of a van full of nuns and the driver (a nun) crossed herself with great haste. I am legally barred from riding within 100 yards of pregnant women. Only the last item on this list is at all falsified.
I have already replaced the exhaust gaskets and "connectors" (the fibrous tube gaskets on the 4-2 collector) and while that improved things a little (i.e. there *was* some leaking), it's still about as bad as it ever was. Whatever wonderful magic baffles were inside the mufflers seem to have long since rotted away, and Suzuki - in the heady caution of the early-smog days - saw fit to weld the mufflers right to the pipes.
And even if they hadn't, I'm sure that the 45 years of rust and corrosion on the pipes will eventually come to roost. I'm also sure that all the flow caused by the loss of baffling is not doing the stock jetting any favors.
So I'm looking for exhaust parts. Not urgently - I've got a lot of backlog on the bike - but looking nonetheless. I suspect even the most nominally baffled look-at-me megaphone would be an improvement on my current situation.
A first instinct might be to get some stock pipes cheap from ebay and cut them off at the muffler. I am ruling this a non-starter, as the stock pipes are double-walled (and the inner wall is quite thin). I don't think I'd be able to make a clean cut through both walls without collapsing the inner one and causing all sorts of issues with flow. A quick look on eBay turned up some listings where people have tried just that, and every single one of them that has an end-on picture has a warped and useless inner pipe showing, so I feel validated throwing this approach out.
Nobody makes aftermarket headers or systems for the 650G. MAC made a 4-1 rumored to be of dubious quality - these rumors must remain such, as it's totally out of stock everywhere, and MAC is dead. Delkevic makes 4-1 systems for almost every other Suzuki of this era, but not the 650, as do a couple other companies.
And to be honest, I don't really want a 4-1. I especially don't want a 4-1 at the cost of my centerstand. What I would like to do is find some headers that fit the exhaust ports and clear the block, then select, construct, or commission 4-2 collectors that slip past all the stock equipment on the bike, then finally select and install some off-the-shelf mufflers that are not so unholy as to require direct ecclesiastical intervention. I could skip all this and commission some headers, but that costs a signficant amount money (vs repurposing) I'd rather save for other things.
It would be irritating (but certainly possible) to kitbash the headers from a 4-1 into something that would feed into a 4-2. Even the first few inches fitting would simplify (and cheapen) construction a lot.
So my big question is: what, if any, other Suzuki fours have exhaust HEADERS that can be fitted to my bike?
I have heard many rumors that headers for the 550 of the same year is compatible.... almost. The exact definition of "almost" is variable according to source. Some people (on the internet) say the 650 ports are slightly too big for it to work, some other people say they're slightly too big but adding an add'l crush gasket makes them fit - other people say the ports are too big AND the bolt pattern is wrong. Some people say that the down pipes are too short to clear the block. Some people (my favorite people) say that the headers fit exactly, it's just that the collectors and muffler mounts downstream don't - which would be perfect.
I think the 550 pipes are slightly slimmer than the 650 pipes - but if the port fits, then I'm not concerned, as aftermarket pipes are singlewall and therefore will probably have a comparable ID to stock 650.
I vaguely recollect - can't remember from where, possibly a wishful daydream or feverish vision - that the 1983? 750ES? headers are partially compatible too.
