ADVrider

Go Back   ADVrider > Bikes > Old's Cool
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 10-22-2008, 06:43 AM   #16
bowerbird OP
BMW R65
 
Joined: Oct 2008
Location: Tucson, AZ
Oddometer: 141
They are bing 32mm CV carbs. Does out=lean? If not then I'm more confused.
bowerbird is offline   Reply With Quote
Old 10-22-2008, 07:50 AM   #17
bpeckm
Grin!
 
bpeckm's Avatar
 
Joined: Apr 2008
Location: Road Island
Oddometer: 5,645
Bing carbs use an idle passage with an idle jet and an air mixture screw. For good, basic information,

read this article

and it is well worth getting the Bing book, which is inexpensive and will tell you more about carburetion than you will ever want to know.....

So YES, the air screw is turned OUT for more air at idle circuit. Generally, turn it out until it stumbles, then turn it back in somewhat. If you are turning it out more than a turn-and-a-half or so, you may need to clean the air passages. Be very careful with spray carb cleaners and soaking cleaners: you don't want to get that stuff on the throttle-plate o-rings, as they are a bear to replace.

Anton has a good thread on rebuilding the carbs, as well


If you find that you are still rich, away from idle, first thing to check is your float levels. Read his article for good detailed instructions.

__________________
XS650 becomes a VT BackRoadRunner
Loving the 80ST
I love projects that take twice as much effort as should be needed. Should be an Airhead motto. (disston)
__________________
bpeckm is offline   Reply With Quote
Old 10-22-2008, 08:03 AM   #18
bowerbird OP
BMW R65
 
Joined: Oct 2008
Location: Tucson, AZ
Oddometer: 141
Thanks, I'll be reading these
bowerbird is offline   Reply With Quote
Old 10-22-2008, 01:13 PM   #19
lkchris
Albuquerque
 
lkchris's Avatar
 
Joined: Feb 2005
Oddometer: 971
Most likely way a Bing carb could be rich is overflowing float.
__________________
Kent Christensen
Albuquerque
'12 R1200RT, '02 R1100S, '84 R80G/S
lkchris is offline   Reply With Quote
Old 10-22-2008, 04:34 PM   #20
bowerbird OP
BMW R65
 
Joined: Oct 2008
Location: Tucson, AZ
Oddometer: 141
One question I forgot to ask...How much fuel should I be looking to see in the float bowl say if I turn the petcock on , then off and take off the bowls?
bowerbird is offline   Reply With Quote
Old 10-22-2008, 05:41 PM   #21
bpeckm
Grin!
 
bpeckm's Avatar
 
Joined: Apr 2008
Location: Road Island
Oddometer: 5,645
I will refer you back to post #5...it is hard to get a consistent test of the actual amount of fuel, but if you gently lift and lower the floats, you can see whether they are shutting of, and opening, properly.

Ideally, the fuel should shut off when the float tops are parallel to the carb. If it shuts off below that (too soon) you may run lean, if it doesn't shut off til later, the bike will run rich.

__________________
XS650 becomes a VT BackRoadRunner
Loving the 80ST
I love projects that take twice as much effort as should be needed. Should be an Airhead motto. (disston)
__________________
bpeckm is offline   Reply With Quote
Old 10-23-2008, 12:41 AM   #22
opposedcyljunkie
Heavyweight Boxer
 
opposedcyljunkie's Avatar
 
Joined: Feb 2007
Location: By the Lake
Oddometer: 4,779
Quote:
Originally Posted by bowerbird
They are bing 32mm CV carbs. Does out=lean? If not then I'm more confused.
Again, I stand by my earlier statement. CV carbs --- out = rich, in = lean. On the CV carbs, it's the fuel that's being metered, not the air. Unlike the older Bing slide carbs (on my R50/2), which does the opposite.

Can anyone else chime in and confirm?
__________________
OCJ
92 R100GS-PD Euro
01 Vespa PX150E - sold
05 Yamaha Fazer FZS-1000
07 R1200GS
opposedcyljunkie is offline   Reply With Quote
Old 10-24-2008, 06:52 AM   #23
bowerbird OP
BMW R65
 
Joined: Oct 2008
Location: Tucson, AZ
Oddometer: 141
I have a cutaway illustration that looks to agree with you. (out=rich)
bowerbird is offline   Reply With Quote
Old 10-24-2008, 11:38 AM   #24
Velvet Elvis
mild mannered adventurer
 
Velvet Elvis's Avatar
 
Joined: Feb 2006
Location: Snohomish
Oddometer: 158
4 out of 5 dentists agree. The Bing CV carbs mixture screws turn in for lean, out for rich.
__________________
Zoinks
Velvet Elvis is offline   Reply With Quote
Old 10-25-2008, 01:27 PM   #25
bpeckm
Grin!
 
bpeckm's Avatar
 
Joined: Apr 2008
Location: Road Island
Oddometer: 5,645
Well, I finally got to where my Bing book is physically, and had a chance to look up whether the CV idle adjustment is air or fuel...

And I stand CORRECTED, you 4 out of 5 dentists, Velvet Elvis, Bowerbird, Opposedcylinderjunkie are absolutely CORRECT. I learned something today.... I guess I just turn 'em in or out to where they work best, and owning two bikes with slide carbs, where the screw is the air volume screw, well........ sorry for the confusion.

According to the Bible of Bing, Chapter and Verse (actually page 8):
Attached Images
 
__________________
XS650 becomes a VT BackRoadRunner
Loving the 80ST
I love projects that take twice as much effort as should be needed. Should be an Airhead motto. (disston)
__________________
bpeckm is offline   Reply With Quote
Old 10-25-2008, 06:32 PM   #26
opposedcyljunkie
Heavyweight Boxer
 
opposedcyljunkie's Avatar
 
Joined: Feb 2007
Location: By the Lake
Oddometer: 4,779
I also have that Bing Bible, and it's a Godsend for us shade-tree mechanics!
__________________
OCJ
92 R100GS-PD Euro
01 Vespa PX150E - sold
05 Yamaha Fazer FZS-1000
07 R1200GS
opposedcyljunkie is offline   Reply With Quote
Old 10-27-2008, 03:49 AM   #27
Beemerboff
Beastly Adventurer
 
Joined: May 2005
Oddometer: 2,210
The Bing book says out for richer , but if you tune it with Colortune plugs you will find it round the other way.

Bing got it wrong. And they sell Colortunes.

And , for what its worth , I found the mixture was right and the bike ran best just of the point where it starts to to stumble when screwing it screw in.

They are not orphans here - the guy who wrote the Ohlins adjustment manual doesnt know that the adjuster on the bottom sets compression and rebound at the same - he thinks it does rebound only.
__________________
Adelaide Hills, Australia. 93 R100 GS, 77 R75/7 ,70 BSA B44VS, , 86 R80 G/S PD, 95 BMW Funduro F650 ST
Beemerboff is offline   Reply With Quote
Old 01-16-2013, 06:23 PM   #28
victor850r
n00b
 
Joined: Sep 2012
Oddometer: 7
HELP¡¡
i need to know how to timing the BMW r65 1981 does anybody can showme a link where i could find the procedure?
victor850r is offline   Reply With Quote
Old 01-17-2013, 03:41 AM   #29
Beemerboff
Beastly Adventurer
 
Joined: May 2005
Oddometer: 2,210
Find a decent hill on a quiet road somewhere, do a few test runs up the hill, pick a point near the bottom and go past it it at say 60 km in fourth, then gas it as hard as you can the another point at the crest of the hill, and note your speed.

Remove the front cover , slacken the Bean can, start the engine and turn the bean can slightly either way till you get the fastest tickover, then turn it clockwise to the point where the revs just start to fall. Mark that point on the bean can.

Go back to the test hill and do another run. Hopefully it will be faster than before, but turn the bean can SLIGHTLY anti clockwise, and do another run.
If it is faster repeat the process until there is no improvement, then reverse the process, turning the can clockwise slightly until the performance just starts to drop.

Then get a timing light, and see where the timing mark on the flywheel has ended up - with twin plugs and 1000cc barrels and pistons in 800 cc heads I ended up around 26 degrees advance, so I could just see the mark in the bottom of the hole.

Or have a dyno guy set the timing on his machine, just tell him you are more interested in pick up between 3000 and 6000 revs than peak horsepower and you will get something that works.

There is a mark on the flywheel which will give you an approximate setting, which will get you to the dyno, but your best position can vary 3 degrees either side of that mark.
__________________
Adelaide Hills, Australia. 93 R100 GS, 77 R75/7 ,70 BSA B44VS, , 86 R80 G/S PD, 95 BMW Funduro F650 ST
Beemerboff is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 06:06 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014