Exhaust question...

I am going to start making my exhaust this coming week and I have a different idea than I originally had. Now I am envisioning 4 pipes straight back (longshots) I want the pipes to go all the way to the back of rear tire. My question is does anyone foresee any problems with having 4 individual pipes?

 

First off, ground clearance, second, making some kind of support bracket to hold them in place and look clean, like no big metal straps bolted to the frame etc.
With that amount of length, they're going to have to bolt up some where down stream of the flange at the head.
Also, depending on the material you choose, they're going to be heavy.

 

Well - it will work, but it may require some carburetor work to make it run properly after -- as long as you're ready for it. You're also going to be losing the scavenging and 'pumping' action that's gained by connecting the exhausts together.

Now - you will need to figure out how to keep the exhaust hot enough to get out the ends of those long pipes -- so you'll want to be wrapping at least the first half of each, unless you're using double-wall pipe -- come to think of it, even then you might want to wrap.

 

Kevin11 runs 4 individual pipes (kicked up) and claims no problems - - even has a video proving it.

http://www.youtube.com/watch?v=K23pNFxGWkE

I would "hide" 4-8 stainless scrubbies in the pipes to at least cut some noise.

 

^^^^ that bike sounds so damned good

 

yes, yes it does

 

+1 on the scrubbies. I've used brass scrub pads in the screamin
eagles to reduce the harshness. So far no more then two at
a time with a 2" (5/8" hole) washer hose clamped at the end of the pipe.
Not only does it reduce noise but I regained some of the power
lossed from the single baffle of the pipes.
I once tried a stainless pad sandwiched between two brassies, but
the power deminished along with most of the sound.

 

You will have to do some fancy bending if you want to keep the use of the center stand (which I find comes in handy for servicing the bike)
I suspect the sound is over whelming with 4 straight pipes and baffles in each one would make it sound and run better I suspect.
I like the idea and the looks of 4 separate pipes. Please keep us posted on your fabrication and post some photos as you go. Thanks!

 

Yeh I use my center stand for maintenance and storing through the winter. The pipes are in the way for sure. While I agree the bike is loud, It's not really overwhelming to me especially with a helmet on. A lot quieter than some V-Twins rolling around out there.

 

I'm with on that one Kevineleven,
Ilive next door to a Harley dealer and they must've had a sale on straight pipes! Sometimes the dishes in the cupboard rattle.

 

If anyone is interested, I'm gonna rework my XJ again relatively soon and put it up for sale once the weather breaks.

 

The effiencies of exhaust changes are not a perfect science, jetting changes for example for example, the richer the the deeper and melow, the leaner he more backrap. Scavenger cones can be used to adjust the powerband. A nice sounding se of pipes can cost you mpg and horespower. Depending on jeting, restriction in the exhaust w/lean jetting can acualy increase torque a lowr rpm's a the cost of high rpm HP.
What is your4 prioity7

 

Does anyone know what he's using for jets? (guy in the vid)

 

Cutand weld,
Just PM Kevinelevin and I'm sure he'll give you the info you need.

 

I'm seriously curious about this "scrubbies" trick...
I have an exhaust on the same lines as kev11.
Only, 4 into 2, 1 on each side guided around ammo can saddle bags.
(haven't quite figured out loading pics yet)
carbs have pods, no jetting.
Sounds great, runs great...(as close to perfect as it can be for my blood)
But....they SCREAM...!
Which, I don't mind in the fast pace sideways of Philly.
Taking a road trip soon and considering the "scrubbies" for the long, solid 5th gear highway mode....
Who here has this "installed" and how do you like it?
Any thoughts...??

Thanks....

 

In my opinion, the scrubbies, or other restrictions need to be a couple feet upstream from the tip, so the sound can re-form as a low tone in the open exhaust tube. A restriction at the very tip leads to a buzzy, raspy note. Longer pipes, or larger diameter make lower tones.

 

I run straight thoughts at the moment on my 81 750. I use 195 main jets and K&Ns it runs ok.
I’m going to be using shorty 12inc silencers soon with removable baffle

http://www.championmotouk.com/product-i ... d9624.html

 

Check around at different sites/stores. Those shorty mufflers go for as little at $19-$20 each I've noticed.

 

I went to the local Harley-Davidson dealership, to speak to the parts representative about what I have heard some people call: “Take offs”.
These are Harley-Davidson parts, that have been taken off a brand-new bike, and replaced with aftermarket performance equipment.
I had heard that these parts called takeoffs, are available to be purchased as used parts. I was primarily interested in a pair of Harley-Davidson Sportster silencers.
The nice fellow working the parts counter told me, a lot of people stop in and ask about mufflers and shocks, and he has to tell them all the same thing, that Harley-Davidson doesn't sell the parts it takes off from customers and motorcycles and sell them to the public.

unbelievably, he told me that actually what they do do with these parts, is to bring them out back and destroy them!

I'm really not sure if that's what they do, or because I rode in on a Jap bike, I was getting my chain yanked by this guy. .

 

I hate starting new threads when one is already going, I realize might not be the same situation, but still I have a question.

Anyway my xj700 has some aftermarket pipes 4-2 and the mufflers were shot, so I took them off during my current rebuild, now looking around I'm finding a challenge to find something that fits....the outlet is 2 inch od and everywhere I look I only find 1-3/4...just wondering if anyone has any idea if I'm just measuring od when I should be lookin at id?

Pretty sure I'm right, thing is I don't really want to dish out anymore than I need to....was wanting something more like a sporty has..straight out..but believe the sizing to be an issue...guess I could cut the pipes closer to the header as it appear a bit smaller closer to the motor.

Ideas?