85 Vmax ponderings

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Thanks again to all who have answered my previous inquiries. I really do appreciate the advice.

These are my latest questions....

Speedometer - If I'm going 35 mph, speedometer shows 41 - 42 mph
When I'm going 55 mph, it's showing about 64 - 65 mph

I know this from the radar goodies on the roadside that show
your speed as you are driving past them.
Also, I've had someone drive along side me, and checked it
that way too.

My question is....is this common on gen1 vmax's? My bike has just over
25,000 miles on it. Maybe the internals of the speedometer worn?

Butterfly Valve - As you look down into the airbox (cover removed, of
course) and look at each of the butterfly valves, the one
on #2 carb stays open a little. The rest are able to set
closed completely.

My question is....how can I get the #2 carb butterfly valve to close
completely? I have went thru the service manual (pdf file) and made
sure the throttle cable 'open/close' correctly, checked the play, etc.
I've tried adjusting the sync screws, too. #2 won't close completely.

Original Color - I have tried the 'color match' web site(s). It goes back to
1986, no 1985 model/color info.

My question is....my vmax has the original paint. It's a metallic darkish
red / almost burgundy type color. I will attach the photo of the bike as
it looked when I bought it a few months ago. Keep in mind, it was
stored in a large storage bin for nearly 5 years. It looks WAY better
now. What color is this stock 85 vmax? I want to repaint it stock color.

Thanks for any help.
 

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These speedos are typically off a bit. That seems a bit much for how slow you were going though. The faster your moving, the more error there is, typically. Your method of checking may not be all that accurate either. Tire size affects the readings. The speedo drive is calibrated for oem tire size.

When you say butterfly valve I assume that is exactly what you mean and not the slides? The butterflies are on the bottom of the carbs, under the slides when looking down thru the throats with the carbs mounted. Only thing I can think of that would make just one butterfly open while the others are closed would be a synch or linkage issue. The butterlies are mechanically operated via the cables. The cables attach to the linkage the linkage operates the butterflies. You say you messed with the synch screws but, did you use a manometer to test synch? I've seen it a couple times where the little tab that the synch screw touches needed a little tweak to get more adjustment.

I've got nothing on the color. It has been brought up on the forum before but can't remember if it was answered.
 
I think most Yamaha speedo's have generally been off by 7% on the optimistic side. I go by my GPS MPH for all my bikes. Even my 2011, FZ8 is that far off... Good to have you here on the forum. Stick around after you get all the bugs outta your Vmax. This place only gets better...
 
Below is a pic from under the carbs clearly showing the butterfly valves, if these are visibly different then you need to re-sync them (I would do an eyeball sync before doing it with the engine running)

Note: when doing the sync it may appear that #1 opens instead of #2 closing, this is Ok because #3 and #4 are holding them open, when you sync the other side of the bike #1 and #2 will begin to close again

How to sync carbs:
http://www.vmaxforum.net/showthread.php?t=3959

vmx1200032-1.jpg
 
http://www.vmaxforum.net/showthread.php?t=17020

Check out KJs attachment in the link.
I believe the color you are looking for is
00KW. DA. Dark amethyst

Just a note: Amethyst was BLUE IN COLOR. The 85's came in red or blue. Even though I've owned a red one all these years, I can't seem to remember the official name of red, or the color #'s from any charts, but I do know that the dark ameythst was so dark blue that it looks nearly purple (to me).
 
Regarding the speedo, mine reads about 60mph at 55mph per GPS, so what you are describing sounds pretty darn close. Speedo healers exist for digital speedos, but I think you are out of luck with the OEM speedo.
 

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