VF500F Cam Spec's '84/'85 vs. '86

Hi All,

Would anyone have an '86 VF500F Factory Shop Manual and a scanner handy?

I'm doing a bit of research on the cam specifications.

Here are the pages that I'm looking for (these are from the '84 Shop Manual - part no. 61MF200)








Many Thx!

 

I'll see if I can get my old one from the owner of my old VF500

 

Thank you sir!

 

You obviously assume the '84 and 85 share the same cams. Well the '85 Honda shop manual 67MF201 (European version?) has different values. I will post relevant pages when I will find my way with photobucket.

Meanwhile I propose the change of this thread's title to VF500 Specifications or something and the inclusion of the Honda shop manual number along with a scan of the 2nd page with area codes, if this is applicable of course.

 

Thank you for the post.

I did not realize the '85 has different intake and exhaust camshafts vs. the '84.

I have always seen them posted together (i.e. Megacycle Cam's website).

I'll check the OEM part numbers in a bit.

I should clarify - I'm interested in USA specs only for this thread. Thx!

 

'84/'85 vs. Late Model '85

'84 OEM part numbers

IF, 14110-MJ8-305
IR, 14120-MJ8-305
EF, 14130-MJ8-305
ER, 14140-MJ8-305

'85 OEM part numbers, up to serial no. 2104566

IF, 14110-MJ8-305
IR, 14120-MJ8-305
EF, 14130-MJ8-305
ER, 14140-MJ8-305

'85 OEM part numbers, serial no. 2104567 to 2111460

IF, 14110-MJ8-010
IR, 14120-MJ8-010
EF, 14130-MJ8-010
ER, 14140-MJ8-010

 

Here are the Specifications of:

VF500F/F (1985) European version (?) as stated in Honda shop manual 67MF201

 

Wow! That's weird. If I saw that I would have assumed it was for the 1986 because of the revised valve clearance spec and the cam differences. Is this really for a European 1985? If so, is it possible that the 1986 revisions hit Europe a year earlier?

 

...and the 30mm carbs!

This is for the 1986 as we know it over here.

 

Thank you for the Post.

This looks to be a slightly different animal than what we have in the US.

I'm interested also in the spec's on page 9-1 - specifically the cam height...

I believe the '84/'85 intake and exhaust cams are taller compared to the '86.

 

The info have for the stock 84/85 cams is:

Intake:
.308" @ .040"
236° duration

Exhaust:
.299" @ .040"
236° duration


Not sure about the 86's. Something makes me think they have the same lift but more duration... but don't quote me on that.

 

Page 9-1 included.

A note on service manual numbers. it seems the "200" refers to 1984 while 201 refers to 1985 and 1986, "MF" is the VF500 so is 61 referring to US while 67 refers to other markets?

 

Here is a bit more intel from the Clymer manual, M329, - to be taken with a grain of salt of course.

This does note a taller '84/'85 cam.

 

Also, for reference, Megacycle Cam's catalog page on the VF500F (this notes the stock '84/'85 camshaft spec's but not the '86, not sure why).

 

So, what's keeping someone from running 86 cams in an 84/85 engine? Are the journal diameters different? I didn't look into that info, if it has been posted, I overlooked it.

 

From what I have heard it is even harder to come by 86 head parts than the 84-85. I believe also that the new profile works in conjunction with the 30mm carbs to alter the powerband for more mid-range delivery.

 

Not sure this is the way to go. We’ll need the official '86 specs (for the US model) to compare but my hunch is that the '86 cam has less duration and possibly less lift versus the '84/'85 model.

This would make sense, IMO, as the '86 carburetor throttle bore was reduced to 30mm compared to the 32mm bore on the '84/'85.

 

+1

My thinking as well.

 

Cam lobe height?? Never heard it put that way. Don't really know what they are calling "height". Thinking is "lift"? Depends on the base circle of the lobes. You can have a different base circle for different cams for the same motor. There's several thoughts about makeing power with cams. One is based on the cam lift and the other is on duration to get the cylinder fill needed. Which both can be changed by using a different rocker arm ratio. Some motors will use a different ratio on the intake vs the exhaust. It all depends on how you want to make power and how you are using the engine. Without a known combination it's all trial and error anyways for the most part by the average builder. I would not base a cam decision on just lift or duration. There are other more important factors to consider first. So it's kind of a mute point.

 

I always thought "lift" to be a counter-intuitive word. My 919, like most newer bikes, has caps that fit over the valve assembly with shims within to set clearance. These caps (or cups) are referred to as "valve lifters". However, the valve is never "lifted" except by the force of the spring which returns the valve to its rest position after being "pressed" down into the cylinder. "Lift"? In my world lift mean moving something upward. I don't get it and would appreciate it if anyone can explain.