TwinMax or Manometer plug in where?

[plc]

Guys,

I am toying with the idea of a gadget to tune the bike (addicted to gadgets for my bike). Forgive me for being slow on the uptake, but where on the carbs do these plug in? I can't see any little screw to remove on the side.

Am I missing something or are my carbs sealed somehow?

Best wishes,
Paul

[bubby-joe]

My R-65 has the vacumn fitting is on the bottom of the carb next to the mixture screw there is another screw, that's where the vacumn gauge or gauges, twinmax or carb balancing device you use hooks up.  Mine wouldn't come free I think someone put loctite on the  screws even with heat they wouldn't budge.  I'm thinking of converting to mikuni's, it runs fair but I've got an annoying lean pop on the right cylinder, just off idle.

[nhmaf]

IF the bike has the north american pulse air system, the hoses that connect the carbs to the snorkel valves in the airbox is what one would pull off to connect the manometer/twinmax/rotameter, etc.   The fitting should be on the underside of the carb where Joe indicates - the one handy thing about the pulse air system.

[bubby-joe]

My pulse fittings are plugged and sealed with a screw and sealer at the head end of the hose to the air box so if this could contribute to the right cylinder lean pop please chime in and explain why... The vacumn ports are found in the scan from my manual and circled in red.   OOOOPs the file is to large, digital photo coming up.  Sucess kind of it's a little grainy but you'll get the idea.

[bruce_launceston]

Hi Paul.

As Joe said the vacuum take off point is the brass tube next to the mixture screw. It will be blanked off with a screw. The screws tend to be very tight, make sure you have a good fitting flat blade screwdriver. If necessary you can give the screwdriver a light tap on the end to loosen any varnish gumming things up.

Aussie bikes won't have any pulse air system tubes in the way.

Attached is a photo of the vacuum take off and also my Manometer which I made with directions from the interweb.

I made mine with 5 metres of 5mm vinyl tubing and a 1 metre steel rule, both from Bunnings plus a few cable ties and a second hand piece of timber.
I filled the tubing with Stihl two stroke oil (available in 100mm one shot bottles) the viscosity is ideal and the colour is easily readable. The fluid is very steady and doesn't need restrictors in the tubing to flatten out pulsing that I read can be a problem.
The black caps on the tube ends are just dust seals for when it's stored.

[bruce_launceston]

A couple more manometer photos ..

[bubby-joe]

I like your balance tube mines quite similar castrol synthetic 2 stroke oil in mine it was free came with a para glider engine.  Your picture's way better to nicely detailed.

[raypond]

G'day Bruce,

Nice pics of your manometer. Mine looks much the same but without the ruler. Am I missing something or is the ruler unnecessary? I just get the levels equal and consider the job done.  There must be a reason the ruler is included in the design but I've never understood what that reason is.

Cheers
Ray

[Rob Valdez 79 R65]

Here is the picture I made some time ago:

[bubby-joe]

 Mine looks much the same but without the ruler. Am I missing something or is the ruler unnecessary?
Ray

No your right the ruler is not necessary it could just as easy be a stick, its just to take the curl out of the hose used and the object is to have the same oil level on each side with the engine running at the proper idle when your done.

[montmil]

The early crafted Mk1-Mod1 $4.00 manometers utilized a yard stick to secure the vinyl tubing. The three-foot "stick" was usually free at the local lumber or hardware store -in those golden days- and an appropriate length. That's the only reason for the markings. You could just as easily strap the tubing to any handy, rigid length of... whatever.

An economical, reliable and safe (mercury free) tool.  [smiley=thumbup.gif]

[raypond]

Thanks for confirming that the ruler isn't really needed. I've been vaguely worried for ages that there was something I didn't understand about the $4 manometer.

[ukzknos]

Bruce

Why isn't the liquid level in the pics of your manometer?

It suggests there is some force already acting?

Steve

[bruce_launceston]

I had also noticed that and wondered if anyone would ask.
I put it down to one of the dust caps on the end of the tube coming off while it was hanging in storage.
If this is the cause it suggests that they must be quite sensitive.

Okay I have just confirmed my own theory. I used the manometer yesterday to retune by bike and put two dust caps on when I hung it away again.
They are odd caps and one cap fits tighter than the other. I have just been out to the garage and the oil level was again out by about 35mm.

As soon as I pulled both caps off the fluid levelled up.

Cheers

[ukzknos]

Got it!

Thanks for double checking