The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: plc on February 13, 2010, 09:20:55 PM
-
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
-
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.
-
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.
-
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.
-
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.
-
A couple more manometer photos ..
-
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.
-
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
-
Here is the picture I made some time ago:
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F72083065%2Fmedium.jpg&hash=b237620036445bc9170475ef6d1c5e334da18628)
-
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.
-
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]
-
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.
-
Bruce
Why isn't the liquid level in the pics of your manometer?
It suggests there is some force already acting?
Steve
-
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
-
Got it!
Thanks for double checking :)
-
It is the air pressure generated by fitting the dust caps. I tried pushing them on at exactly the same time... dumb. Pull the caps off and the fluid levels up.
BTW, Drug out the mano' to synch cables at idle and cruise rpm and noticed my purple 7.5wt official BMW manometer/fork oil had bleached out as the tool was hanging and stored in the shop! Kinda golden color now. May go with ATF or something else more colorful. Still works just fine but less easy to see against my wooden four-foot long yard stick. So impressed with Bruce's Adel clamps that I added some to my stick.
Monte
-
They are very sensitive 1/64th or less of a turn to only one adjustment screw makes a very large oil level difference from one tube to the other making exact balancing almost a breeze. Mine came to the exact same level on each side but you have to allow any changes to the settings to settle down. Very small adjustments make a big difference. Just rough tuned right line was 7 inches away from the left tube each movement can be seen almost instantly as you get close then slow down and let each tiny movement settle till both levels are the same. I've used mercury gauges in the past and this is a lot more sensitive and cannot harm you, the environment, or the engine if a line comes off and sucks your oil into the engine no real harm just a small amount of smoke. Don't want to burn mercury in your engine, very bad thing..
-
I have a clear line coming out of those two orphaces that disappear under the airbox. I was looking at them when my coil burnt up. this afternoon.
-
I have a clear line coming out of those two orphaces that disappear under the airbox. I was looking at them when my coil burnt up. this afternoon.
Inside the airbox, you'll likely find the "air injection" hardware attached to the tubing. Lots of owners delete this system. Monte
-
There was a thread on the BM Bikes & Riders forum a short while back about a theory that adding a balance tube between the two vacuum take off points would help smooth out the running.
Maybe someone has linked yours for this reason.?
I don't think it was a proven theory with one person saying that if it was worth doing BMW would have done it from the factory.
Some riders were going to give it a try I think.
-
Hi All,
Thanks for the advice guys. I have bought a Carbtune Pro to balance my carbs; I needed something portable and easily stored away from little fingers in my confined storage space.
When it gets here I will give it the tune up it is long overdue for.
Best wishes,
Paul
-
a theory that adding a balance tube between the two vacuum take off points
Hi Bruce
I can't understand what would be achieved by linking these two vacuum points?
As you say, if it helped then the factory would have done it! :-?
-
looks original. I turned the picture upside down so some of you don't have to look at the screen upside down. ;D
-
looks original. I turned the picture upside down so some of you don't have to look at the screen upside down. ;D
The one next to the mixture screw in your picture is that a plastic tube with a screw in it or is that one of the lines to the airbox, that is the vacumn hookup position. The black and metal hose is the air inject system and is for most disconnected and removed or plugged at the head end and left in place, mines left in place and plugged
-
the plastic tube goes the the airbox. I'm not sure on the air inject system. sounds like something I should take off. I havent tackled any carb issues yet. once I replace the coil I burnt up last week I can start diagnosing the inconsitant carb issues.
-
I'm not sure on the air inject system. sounds like something I should take off.
A good article on what to do with the air system.
http://bmwmotorcycletech.info/pulseair.htm
Whatever you do, it's pretty easy. Just my speed. [smiley=happy.gif]
JMcC