4 to 1 Exhaust... what's the truth?

[kilog55]

i want to do that to my 850 but Nessism mentioned the muffler mount changed in 82 and no one lists a complete exhaust for an 850 but said the 750 would work fine

[doctorgonzo]

I'm not touching my stock until ready for a swap for sure. I have TWO missing header bolts, but it doesn't leak. One is sheared off and will have to be extracted, the other I think is just gone. So when it comes off it's probably off for good.

[UncleMike]

I'm not touching my stock until ready for a swap for sure. I have TWO missing header bolts, but it doesn't leak. One is sheared off and will have to be extracted, the other I think is just gone. So when it comes off it's probably off for good.

Not that it's great, but missing two exhaust header bolts is a damn site better than two exhaust gasket bolts...

[Shin-Ken 1074]

The critical issue with 4-1 systems is that to improve performance, and provide better fuel economy as the engine will be running much better with the exhaust gas being scavanged more efficiently through the 4-1 system is to have the headers tuned to the engine and the muffler designed to work with the headers. Off the shelf items may work and most bikes show some level of improvement but to see what can really happen to your bike fit a tuned system built by an expert. Making tuned headers is an art and it may take time to find someone who is able to build a system, but worth it in my view, cheers.

[Mark M]

Off the shelf items may work and most bikes show some level of improvement but to see what can really happen to your bike fit a tuned system built by an expert. Making tuned headers is an art and it may take time to find someone who is able to build a system, but worth it in my view, cheers.

Very true, but you have to remember that most GS owners are not interested in an exhaust system that doubles the value of their bike.

I wish V&H would build a street version of their drag pipes, with the collector underneath the engine instead of beside it. Keep the same short, equal length primary tubes and the true megaphone tailpipe (with a reverse cone to remove the torque drop in the midrange) and a small muffler section after the meg. I would pay new prices for that in a second. But they don't seem to be interested... Guess I will have to make my own, then.

Mark

[doctorgonzo]

Very true, but you have to remember that most GS owners are not interested in an exhaust system that doubles the value of their bike.

I wish V&H would build a street version of their drag pipes, with the collector underneath the engine instead of beside it. Keep the same short, equal length primary tubes and the true megaphone tailpipe (with a reverse cone to remove the torque drop in the midrange) and a small muffler section after the meg. I would pay new prices for that in a second. But they don't seem to be interested... Guess I will have to make my own, then.

Mark

Indeed, guess we should count ourselves lucky that there are any 4 into 1 pipes avalable at all for 30 year old bikes.

[mortation]

Very true, but you have to remember that most GS owners are not interested in an exhaust system that doubles the value of their bike.

I wish V&H would build a street version of their drag pipes, with the collector underneath the engine instead of beside it. Keep the same short, equal length primary tubes and the true megaphone tailpipe (with a reverse cone to remove the torque drop in the midrange) and a small muffler section after the meg. I would pay new prices for that in a second. But they don't seem to be interested... Guess I will have to make my own, then.

Mark

Something like this?

[doctorgonzo]

Something like this?

I've seen those ebay, not sure what to think about them.

[lurch12_2000]

I've seen those ebay, not sure what to think about them.

I assume these have to be removed to change the oil and filter?
Looks like you would have to make your own custom hanger to hold up the back end too?

[doctorgonzo]

I assume these have to be removed to change the oil and filter?
Looks like you would have to make your own custom hanger to hold up the back end too?

Yeah, it looks like both those would be true. Oh where are you Kerker, why did you have to fade away!
I don't like the look of that X pipe really, plus the downsides you mention, plus it's over 400 and I can get a V&H for 300. I'd already have my V&H if the last 6 weeks hadn't been spent replacing the stator once and the R/R unit twice. Could have bought the pipe for what that cost me.

[Mark M]

Something like this?

Nope, those are simply snake oil and no better than the other commercial headers available. They are available, however, so that is a plus. I was thinking of something like this:

http://www.mpsracing.com/products/VandH/pipes.asp

But set up to have the collector underneath the engine instead of beside it.

Mark

[doctorgonzo]

Whoa... those are weird as well. My fist GS was an 81 gs1000S with the factory 4 into 1 (you don't want to know what hapened to that bike). That was a nice looking exhaust love to find one of those new (for less than the fortune they'd want for it).

[Mark M]

Whoa... those are weird as well.

Not weird, functional. The header twists the way it does to get the primary tubes all the same length and keep the overall length down. It exits to the side so that the bike can be lowered as low as possible, since this is a drag only system. It uses a megaphone tailpipe because that is the optimal power producing setup and it looks like they have a reverse cone on the meg, which helps kill the torque dip at around 1/2 the tuning rpm range.

4-1 headers combined with a megaphone are the optimal power producing set up, which is why the drag racers and F1 use them almost exclusively. Everything else is inferior in terms of maximum output.

Mark

[doctorgonzo]

That all makes perfect sense. I just don't like them cosmetically, matter of taste.

[andrewclaycomb]

with the sidewinder exhaust you will lose cornering clearance. Sometimes by a lot depending on the bike.