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All that stuff would work.

I personally use Morgan "gauges" - I use to use mercury manometers that got broken, don't care much for the needle-type gauges.
The Morgans work like manometers, but don't use any mercury or liquids - instead they use calibrated stainless steel rods, so there's no danger of aspirating anything into the engine, and will never corrode.
It's a $100 tool, but you get something that will last several lifetimes, and the advantage of being able to work on 4-cylinders.
To actually use them on a 450 is straight-ahead. Back off the idle screws (the "flippers") all the way, then using the handlebar throttle cable adjuster increase the rpm to about 3,000. While it's running adjust the individual cable adjusters on the carb till the gauges read the same (actual value is irrelevant). Now the carbs are "synched".
Then loosen the handlebar throttle cable adjuster, turn the idle screws up till it idles and the gauges read the same. Now the carbs are "balanced".
Then adjust the mixture screws for maximum rpm, check to see if the gauges are still the same - may need to go back and forth with the idle screw/mixture screw a couple of times, and Bob's yer' uncle.......

https://www.carbtune.com/
 

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Discussion Starter · #22 ·
So...I am trying to figure out the quickest, cheapest, and low risk way to do this...I literally have none of the tools needed to drill and tap a hole...and probably will never do it again.
Anybody know of anyone who can do this for me in the Hartford, CT area?
What size vacuum tubing do you need to use with the motion pro vacuum adaptor?
https://www.motionpro.com/product/08-0218
All the vacuum gages I see are 1/4" tubing...
Has anyone ever accomplished this by drilling through the rubber that connects the intake and the carb? I would feel more comfortable doing that myself since I could replace them if I f'up. I don't think i would need to tap the rubber either so i wouldn't need all those tools, just a drill.
 

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........Has anyone ever accomplished this by drilling through the rubber that connects the intake and the carb? I would feel more comfortable doing that myself since I could replace them if I f'up. I don't think i would need to tap the rubber either so i wouldn't need all those tools, just a drill.
I tried it that way once, long ago - it's really hard to drill a clean hole in rubber, and it may not be as easy as you think to replace those rubber parts these days.
It's not that big of a deal to drill the aluminum, and you can get an appropriate tap to cut the threads for a couple of bucks.
They also have those "barbs" with a 6 mm thread, which I opt for - a 6 mm tap will prove useful in the future for a lot of things on these old bikes.
Hoses - whatever fits, it's not critical.

https://www.motionpro.com/product/08-0219
 

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Discussion Starter · #24 ·
I need a M5 tap for the 5mm vacuum adaptor with a sliding handle tap wrench correct?
A center drill. What size?
A punch. What size?

What size ID tubing goes over the vacuum adaptor to connect it to the gage?
 

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I need a M5 tap for the 5mm vacuum adaptor with a sliding handle tap wrench correct?
Well, uh yeah - though you'll probably only use that 5mm tap once in your life. About the only 5mm screw on a 450 is the tach drive output cover. Everything else is 6x1.0

A center drill. What size?
Something slightly smaller, maybe 5/32" or so.....

A punch. What size?
Anything with a point......

What size ID tubing goes over the vacuum adaptor to connect it to the gage?
Whatever tubing comes with the gauge will probably work fine.
You'll figure it out.
 

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Discussion Starter · #26 ·
So...I amazed myself.

I was able to drill and tap the holes for the 6mm motion pro vacuum ports. I installed 145 main jets and new plugs.

However, I cant seem to adjust the left side carb.

The right stays steady. When i try to give the left more throttle to increase the vacuum it does nothing.
The right @3k rpm is about 15 inHg, but the left is stuck at 8 inHg.

Thoughts?
 

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Time to take that left carb off and go through it again and make sure all the jets and passages are clean.

Make sure the throttle piston moves freely and is not stuck. It should move up and down easily when you blow through a straw (look up the straw test) into the carb's intake passages.
 

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So...I heard a rumor that the stock setup on a CB500T enging is #38 pilot and 145 main jets? Can anybody verify this?
Also, I'm thinking about installing different air filters. I heard their is a model of K&N that works well. Anybody know which ones?
Yes that is correct
 
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