VF500F Aftermarket Exhaust Systems from Back in the Day

That wasn't my pipe so I don't know the diameter, sorry. Yes the factory bikes did split the fronts from the rears and I couldn't tell you why. With all the money in the world, Mama Honda could certainly have built a 4-1 for the race bikes but they didn't. That should tell you something. The Castrol RC45's had switched to a dual exit as well. Why? I can't speak for I4's but I would guess that a 4-1 for a 1st gen isn't necessarily the Holy Grail. Not to say they can't make power but that there are alternatives to design when choosing a custom pipe. I ran my rears separate from the fronts and without messing with the A/F mixture yet and without a carb sync, it pulls really well despite a drop of 3 teeth in the rear from what I was use to. I'm sure once I address the sync, I'll have a nice running street bike. Whether my pipes make or lose power is irrelevant to me because my options were 0 in the aftermarket. Did I feel guilty at the time not making the rears equal length, yes. Am i sorry now, No.

 

Well look at it a different way and you may decide it is better to have unequal length pipes. On our little race bike of yesteryear we had a factory production Kerker pipe with mandrel sharp bends and a long reverse cone muffler after the collector. The bike ran well and had it's own sound. Not like most I4 motors. It had great mid-range pull. We then went to a hand made Kaz Yoshima header. Which had no mandrel bends but continuous curved bends,equal length tubes with a short straight tube for a muffler. This gave the bike faster reving and greater top end. It also sounded like the screaming 1000cc big bore bikes of the time. Our lap times reflected the increase we felt we got with Kaz's pipe. That's about the only real increase I experienced with motorcycle exhaust, besides lost weight over stock systems.

I have been playing with muscle cars exhaust systems and have worked with a few knowledgeable people. One thing we have kicked around is the different pipe lengths within a header side. For the average racers trying to build a "Tuned" header is almost impossible. Trying to get the wave pulse to hit the exhaust port at the proper time is almost impossible without lots of experimentation and theory calculations. Plus it has to match the cam being used and basically works for all out top end power only.

Now with that said. We do know longer pipes will increase torque and shorter pipe will increase the speed of rpms to certain extents. Working with eight cylinders with different length pipes mixed per side may be the best of both worlds on the street. Some cylinders will favor more for torque and some for easier reving/top end depending on pipe length of that cylinder. Then you put a balance pipe in the system past the collectors about 15" and the mid range picks up. So you have different tuning per cylinder sort of speak which has it's advantages on the street. The bad is your intake manifold feeds all cylinders through 1,2 or 3 carbs for most. So you will have slight different A/F for each cylinder. Which with the right tune you'll never notice. But on a motorcycle where you have one carb for each cylinder you can tune each cylinder separately. Provided you have a dyno and an oxygen sensor for each exhaust pipe for perfect tuning. Personally I don't think a good tuner would have to go that far for a street machine.

So after all that rambling I don't think you made a mistake having unequal length headers. It may even be better not to have equal length for street use. Can I actually prove this as fact. No not really. Just seat of the pants feel with dragstrip times and street driving characteristics. Plus what a few others have experienced. Something to think about though. I think diameter of tubes play a bigger part than length.

 

On number 95 - what am I looking at. Is that the header. Are does the exhaust exit the pipes in the front and the ones pointed up and the ones going to the left are going to the exhaust pipes.

 

Thanks Hopit88 thats the picture I was trying to post.

I don't think my VF1000F has the ground clearance, but I like how the muffler is mounted under the engine on the Buell Lightning.

 

A bit more intel on the 'droner' engine, a nicely done CAD model of a V4 cylinder layout with a 360° crankshaft (source: stjepantisljar, YouTube)

[video=youtube;gxWj-2MHxUQ]http://www.youtube.com/watch?v=gxWj-2MHxUQ&feature=player_detailpage[/video]

 

I posted in this thread earlier with videos before/after a Mac 4-2 install. I finally got sick of the loud buzziness and installed some baffles into the Mac "mufflers". First I took them to a local big-time custom exhaust shop here in Montreal, where they told me they could do NOTHING for me even though I explained exactly what I wanted including some detailed drawings.

Figuring they are idiots, and I am MacGuyver, I bought a length of pipe from them and said I'd do it myself. I fabricated a couple of slip-in baffles, in less than a hour, and this is the result. It sounds GREAT, very aggressive low-frequency rumble, no more BUZZ, and definitely more back pressure to get me back my stock driveability.

After video:

YouTube - ‪vf500f Interceptor, Mac exhaust, homemade baffles‬‏

Stock video and just crappy-mac-muffler videos here

YouTube - ‪vf500 Interceptor‬‏

and here:

YouTube - ‪vf500 Interceptor, Mac exhaust installed‬‏

 

Italian Galassetti 4-2-1 1 to 3 and 2 to 4 junction for the vf500f. Good loud sound and good performance. Here on my vf400f

 

i know these are getting hard to find so i wanted to let everyone know i have a set of vance and hines headers for sale for the vfr500. they are in good shape with the hardware.

 

As you mentioned 1 to 3 and 2 to 4 seems to be the best way to go. But if I well remember it's not referred to the cyilinder number, but to the firing order, so that on the vf400/500F the right pairing would be left back with front left and right back with right front.
Am I wrong?
There are so many header software out there. Would be helpful if someone has to upload configurations and see what comes out.
Pietro

 

By the way, could you measure the pipes lenght, just to check if they have same lenght?