VF500F Aftermarket Exhaust Systems from Back in the Day

With the right jetting the hindle system is the possibly the best out there. But there are a handful if draw back the lower hanging pipe means under extreme lean angles it will drag my center stand was already of the bike before I bolted the header up but been told you can't run it anyway and also had to take a bunch of the chin fairing to make it fit but the sound is drugging music to my ears!

 

I have a yoshi 4-1 header for your bike crusty.

 

More information on what is inside the stock collector box (photos courtesy: GazVF500)

 

hmmm I wonder if that is the same as the VF1000R?

 

It's very similar.

 

Just the header system or does it have the muffler?

 

Just the header.

 

That's different, suppose you could just use a universal slip on with it? I would imagine the yoshimura can would be a little better suited for it.

 

Im sure you could go on ebay and find a pipe with the mid pipe make it work its what I had to do the pipe on my 500 was made for a r1.

 

hmm matt we may have to talk...

 

Let me know I've been getting rid of all the stuff I don't use or want tired of all this crap.

 

In the '86 oil pan conversion thread the topic of exhaust systems came up (pan clearance).

In thinking about the VF500F's exhaust system a bit more I wanted to confirm the firing/exhaust order to get a better idea as to why a 4-1 system (or paring the 1|3 and 2|4 cylinders in a 4-2 system) works best on VF engines having a 1-4-3-2 firing order.

I have added a sketch to help in understanding the exhaust 'pulse' sequence which I am noting as 1-2-3-4 (A-B-C-D).

I'd appreciate a double check by other VF owners to see if I have this correct.

Many thanks!

 

That's a good sketch, but it doesn't really highlight the problem. In the bottom sketch it looks like all sequences are evenly spaced. Skew the 1-3 (or 2-4) to one side by 90° of crankshaft rotation and you have a better idea.

It's more like this, consider it a chart from 0-720° of crankshaft rotation. The "="s signify the exhaust pulses. Where they overlap is the issue.
1---===------
2-===--------
3---------===
4-------===--

 

Jamie if you would just build us a hindle replica then we wouldn't need this thread lol

 

The pulse diagram is very helpful. Thank you.

If I could ask, I am not sure I understand the skew part, could you go into a bit more detail on this?

I've attached a sketch.

 

Yeah seriously Jamie

 

The dedication in this thread gives me the warm fuzzies.


Great pic of the collector box cut out!

 

According to your sketches there's always a cylinder firing meaning there's always a cylinder making power.

 

OK, maybe it's easier to start with an inline four. Since the cylinders are all in a line the firing order is even. The definition of "even" is as follows:

First cylinder fires
180 degrees of crankshaft rotation
Second cylinder fires
180 degrees of crankshaft rotation
Third cylinder fires
180 degrees of crankshaft rotation
Fourth cylinder fires
180 degrees of crankshaft rotation


Now, consider a V4 where the front two cylinders are 90 degrees apart (crankshaft reference) from the rear:

Cylinder #1 fires
270 degrees of crankshaft rotation
Cylinder #4 fires
90 degrees of crankshaft rotation
Cylinder #3 fires
270 degrees of crankshaft rotation
Cylinder #2 fires
90 degrees of crankshaft rotation

Let's not forget that these engines are four strokes, which means the cycle repeats every 720 degrees of crankshaft rotation. The 90 degree separation is what makes the V4 great, it produces a bang-bang of power that is hard to beat. It's really the marriage of an inline four with a v-twin, if you will.

 

Thanks for the post.