Author Topic: Accelerator Pump Settings  (Read 10648 times)

zrx2000

  • ROV Junior Member
  • *
  • Posts: 18
Accelerator Pump Settings
« on: September 24, 2006, 12:51:59 PM »
After rescuing the pilot adjuster screw on my '83 rear carb I am now trying to get the accelerator pump set correctly.  There are two settings I am wondering about.  First, what is the correct length of the tie rod and what should the effect feel like for a properly adjusted rod?  Second, what is the correct setting for the stop screw that limits the travel of the cam against the diaphragm in the bottom section of the accelerator pump?  I find it sad that the maual provides no specification for such an extremely important component of the bike either except that the rod was set correctly at the factory.

Thank you.

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #1 on: September 24, 2006, 07:16:03 PM »
working backwards:

i've never seen an 83 carb where the stop screw actually makes contact durring it's normal travel. i suspect it was used on other carbs besides this one.

the only spec given for the length of the rod is a service bullitin that said to increase the length by 5mm, total length from the bend to the end not to exceede 60mm.  set it where it works best.   if you can tell where it was previously set by discoloration on the threads, i'd start there, you'll be close & i've found unless it's severly off it's not as critical an adjustment as you'd think...

BTW, congrats on fixing the adjuster bolt, i'd REALLY, REALLY like to see pics....

--Lucky
1982/3 XZ550 Touring Vison, Gold on Black

motoracer8

  • ROV Senior Member
  • ****
  • Posts: 430
  • Ride there
Re: Accelerator Pump Settings
« Reply #2 on: October 02, 2006, 07:31:57 PM »
You measure the injection quanity. Thats what you are dooing when you adjust the little rod. There is no accurate measurement for rod length.You have to measure the amount of fuel that comes out of the pump nozzle. That is 0.25cc per one compleat opening of the throttle, and you want to measure both front & rear cylinders. Make shure the float level is correct, and the carb is full of fuel. The little vile I use for measurement is a tool set I got many years ago to adjust Webber carburetors on cars. I have no idea if the stuff is still available. But the measurement device has to be small enough to fit down in the carb under the pump nozzle to get a accurate measurement. Several of the Vision carbs I have checked inject too much fuel, whitch makes them stumble right off idle. The 0.25cc measurement came from the Yamaha technical department in 1985.

Ken G.
83 Vision and 11 others, Japanese, German and British

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #3 on: October 02, 2006, 08:27:22 PM »
Good info, a small syringe could be used to measure the output. i have a plastic one but is graduated in ml (so 2.5 ml = 25cc's? is that right?)

got any more tidbits? how did you come across that one?
1982/3 XZ550 Touring Vison, Gold on Black

YellowJacket!

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 5434
  • Don't blame the economy...blame the management!
    • My Vision Blog
Re: Accelerator Pump Settings
« Reply #4 on: October 02, 2006, 09:22:49 PM »
2.5ml = 2.5cc.  Used interchangeably.  Being a healthcare worker, I can get a few syringes (clean of course) if you need.  I can get anywhere from 1ml up to 50ml.

David


Living the dream - I am now a Physician Assistant!!   :-)

motoracer8

  • ROV Senior Member
  • ****
  • Posts: 430
  • Ride there
Re: Accelerator Pump Settings
« Reply #5 on: October 03, 2006, 09:56:21 PM »
David, The syringe would have to be quite small to fit in the carb, and still open the throttle all the way. The little vile I use is 1cc total and is graduated in 10th's, the number I gave is 0.25cc, or 1/4cc. The original setting for the 82's was 0.50cc, or 1/2cc. Whitch later determined to be too much. The update kit for the 82's carb & air cleaner, service bulliton M84-019 had these settings. The 83's were supposed to have the lower volume. Every one I have checked has had to be ajdusted. I have seen almost no fuel, to way too much.

Ken.
83 Vision and 11 others, Japanese, German and British

YellowJacket!

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 5434
  • Don't blame the economy...blame the management!
    • My Vision Blog
Re: Accelerator Pump Settings
« Reply #6 on: October 03, 2006, 10:11:27 PM »
Good advice Ken.  Thanks.

David


Living the dream - I am now a Physician Assistant!!   :-)

Extent

  • ROV Senior Member
  • ****
  • Posts: 812
    • Levanthia.com
Re: Accelerator Pump Settings
« Reply #7 on: October 03, 2006, 11:04:09 PM »
This is awesome, I've been trying to figure out for forever how exactly to set up the accelerator pump.  Who would have thought it could be so easy.
Rider1>No wonder, the Daytona has very sharp steering and aggressive geometry.  It's a very difficult bike for a new rider.
Rider2>Well it has different geometry now.

zrx2000

  • ROV Junior Member
  • *
  • Posts: 18
Re: Accelerator Pump Settings
« Reply #8 on: October 06, 2006, 10:23:52 AM »
Thanks for the great info!  i guess this measurement should be attempted with the carbs on the bike but I'm worried about dropping something into the engine.  Is there a way to independently adjust each carb?

thank you.

motoracer8

  • ROV Senior Member
  • ****
  • Posts: 430
  • Ride there
Re: Accelerator Pump Settings
« Reply #9 on: October 08, 2006, 09:31:53 PM »
There is only one pump assy for both carbs, but sometimes the check ball below the nozzle will stick, so one nozzle or the other will not squirt the correct amount. The little vile I use has a rolled top edge and I use a 6'' piece of small gauge safety wire around the vile then slide a small oring up from the bottom to hold the vile in place, now you can dangle the vile down in the carb under the nozzle and hold it in place. The vile is made from glass, some plastics don't like gasoline very much. You might try to find a small measuring device from a place that sells test tubes, graduated beekers and such. I have a 250cc and a 500cc glass beaker I measure fork oil with, that came from one of those places.

Ken.
83 Vision and 11 others, Japanese, German and British

kwells

  • Visionary Grand Master
  • *****
  • Posts: 2876
    • WellsMoto
Re: Accelerator Pump Settings
« Reply #10 on: October 17, 2006, 05:48:55 PM »
I went to a pharmacy and bought a newborn feeding syringe...comes with a small tube extension too.....$3
...a vision is never complete.

www.wellsmoto.com

Jimustanguitar

  • ROV Senior Member
  • ****
  • Posts: 676
Re: Accelerator Pump Settings
« Reply #11 on: May 27, 2012, 02:10:08 PM »
the only spec given for the length of the rod is a service bullitin that said to increase the length by 5mm, total length from the bend to the end not to exceede 60mm. 

I'm looking at handwritten notes from that bulletin that dpequip scanned into this post: http://ridersofvision.net/rovforum/index.php?topic=12390.0

I'm a little curious because the sketch doesn't show the entire accelerator rod, and Lucky's comment says "from the bend to the end"... When I lengthen the rod to this measurement (measurement A in my picture) I'm running out of threads and the rod falls out of the adjuster. Should I be measuring A or B in my picture?

Thanks guys, happy Sunday. Have a great holiday tomorrow, lots of beer and cookouts. Thanks Vets!

Jim

Rikugun

  • Visionary Grand Master
  • *****
  • Posts: 3216
Re: Accelerator Pump Settings
« Reply #12 on: May 28, 2012, 06:51:20 AM »
Don't believe everything you read. This is just my opinion but those comments by dpequip are bogus. I thought he had something until I started to do my own research and consulted with the carb guru here.

All the more reason to be accurate and accountable for your comments. Someone using the search feature later gets misinformation.  :(
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

dpequip

  • Visionary in training
  • **
  • Posts: 29
Re: Accelerator Pump Settings
« Reply #13 on: May 28, 2012, 08:46:09 AM »
Anyone can think the setup instructions are bogus I really don't care. I'll keep using them because I know they work. If you find them helpful use them but if you want to reinvent the wheel feel free.....  These are not my notes.  The source of the hand written notes was our Yamaha Technical rep in 1984 "Back in the day" when these bikes were being sold brand new.  I used those instructions to setup over 20 new bikes out of the crate and they worked.  All I can say is the instructions had to be followed to the letter and everything had to be done or they would not work.  Setting the Idle CO % is also a big deal in getting a Vision to run right. Unfortunately, most people don't have access to a Exhaust Gas Analyzer to correctly set CO %.  This makes setting up a Vision to run right a difficult proposition at best.  The bikes as setup per the instructions were right as I was the only one in the dealership that set these up.  These setup notes ONLY apply to 1982 US Spec models that have the vacuum flapper door in the airbox mod kit installed. The instructions also assume the engine is in new condition, the YICS box works as it is suppose to, and all the passages in Carbs are clean and unplugged.   Unfortunately many of those assumptions are not valid today since these bikes are almost 30 years old.  Because of that, the settings may have to be adjusted to compensate but they should give you a good baseline to start from.  One other major difference is the gasoline they sell today has no resemblance to the gasoline that was sold in early 1980's.  In these small engines the current gasoline ( I call it weasel piss) sold especially that with ethanol blended in it make motorcycle engines in general run worse and hard to start.  Ethanol free gas makes a difference in these engines but that is a different subject for a different post.   Whether these settings work on other models or other world market models I have no idea or make no claims they do.  They definitely don't apply to 1983 models (Which I think this thread asked about) which have carbs that are a whole different animal.   
1982 Yamaha Vision Owned Since New.
Mods:Euro Primary Gear set, Euro footpegs & controls, Yamaha 1/4 Fairing, Braided Stainless lines, Forkbrace, Tapered roller bearings in steering, '83 rear Shock

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #14 on: May 28, 2012, 08:53:08 AM »
Jim, Your rod is FUBARed. it's not supposed to have that bend in it, it should be straight like the drawing. you need a new one. PM me an address & i'll drop one in an envelpe for you unless you already have a spare.

Rikigun, I think it's more likely tha the doccument Dpequip scanned is from a Yamaha Rep, I think that a lot some of the info on it is inaccurate, such as increasing the oraface size on the nozzle. More likely, that we know more after 30 years, than they did then... or the Rep got fed some bad info at a meeting.
1982/3 XZ550 Touring Vison, Gold on Black

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #15 on: May 28, 2012, 08:56:40 AM »
Dpequip, we posted at the same time..  the section thats crossed out, that looks like it's saying to increase the nozzle, whats up with that?
1982/3 XZ550 Touring Vison, Gold on Black

Night Vision

  • Contributing Member
  • Visionary Grand Master
  • ****
  • Posts: 4503
Re: Accelerator Pump Settings
« Reply #16 on: May 28, 2012, 11:44:56 AM »
Jim, Your rod is FUBARed. it's not supposed to have that bend in it, it should be straight like the drawing. you need a new one.

maybe that IS the correct rod for the rare 82 carb with the stop screw on the accelerator pump... no?
if it ain't worth doing it the hard way....
it ain't worth doing it at all - Man Law
 ;D


if it ain't broke..... take it apart and find out why


don't give up.... don't ever give up - Jimmy Valvano

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #17 on: May 28, 2012, 04:56:15 PM »
Anything is possable, i've never seen one bent up like that. Has anyone else?
1982/3 XZ550 Touring Vison, Gold on Black

Rikugun

  • Visionary Grand Master
  • *****
  • Posts: 3216
Re: Accelerator Pump Settings
« Reply #18 on: May 28, 2012, 05:16:06 PM »
My 2 sets of '82 carbs are different but neither has an accel rod bent like that. Also neither has the stop screw feature.

Quote
Rikigun, I think it's more likely tha the doccument Dpequip scanned is from a Yamaha Rep, I think that a lot some of the info on it is inaccurate, such as increasing the oraface size on the nozzle. More likely, that we know more after 30 years, than they did then... or the Rep got fed some bad info at a meeting

Perhaps and maybe I could have used a little tact  :-[ The PDF I recall was in a spreadsheet form but had similar info but no pictorial depiction of where the measurements were to be taken. As I recall the 50-60 mm rod length wouldn't work on my first set. It was suggested the rod had been cut by a PO but even with magnification I can't see evidence of that.
« Last Edit: May 28, 2012, 05:25:30 PM by Rikugun »
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Lucky

  • Visionary Grand Master
  • *****
  • Posts: 9877
  • That's my baby!!
Re: Accelerator Pump Settings
« Reply #19 on: May 29, 2012, 08:18:51 AM »
Kudos to whoever bent that bar up though, nice work! lol
I have your new one in hand.
1982/3 XZ550 Touring Vison, Gold on Black