AKVision's Vision. Out in the sunlight

[rhpaw]

but it's really hard when people do stupid stuff like mix up the jetting  >:(

hey!!! dammit, I was overthinking it.. probably all the damn internets

[inanecathode]

AK & RH
Drop me a pm please, i could do a few mid week short rides with you guys before next weekend ;)

[Rick G]

I use a jewelers loop . Harbor freight , 1.99.

[rhpaw]

So we went for another ride today.. This time we had the new 127.5 jet in the rear cylinder. Pop left in the morning when I was still herding kids around, when he came back  it was "OH, this is great, we fixed it!!"

Later on in the day when it started to look like rain we headed north to 285 for a fun run.
It started to come down and we pulled into a lot.
"It's still acting wierd, kid."

Hmm.. I took it for a spin. Y'know, in my opinion it still felt like the Vision 'on a good day'.. Low speed power and response is fine, but as soon as you get it above 5.5k, all bets are off whether it will pull. Granted, Pop was able to take the bike to 8k on the freeway in 3rd, but he was having stumble and hesitation problems depending on how the throttle was turned.

Good point id that the idle on the bike is rock solid at 1500 cold or warm. low rpm response is good.
He loves the Pirelli Sport Demons, the 83 shock and the brakes are top notch. Also the vibes I was complaining of are supposedly no longer present.
We drove around in traffic for a while and although the bike got hot, it cooled down pretty fast when we started moving.


Let's see.. for high rpm stumble we have
1. accelerator pump length.
2. carb sync
3. flapper box mods?

The only vac leak in the system is the throttle shaft, and we have seriously minimized that with the addition of lithium grease, additional 6cm oring and shaft spacers.
Mix screw settings should not be in the loop now, correct?

Too bad we'll get it fixed a tee then all die of swine flu next week.

[QBS]

Bike operates on secondary/high speed circuits above 4000 rpm.  Sure you got them squeeky clean on both carbs?  You do know about the emulsion tube jets that go into the carb bodies from the bottom, right?  I would look at secondary circuit problems before I chased any of your three listed suspects.  None of them really apply above 4000.

[akvision]

Q!
We completely re-dis-assembled both carbs. We took out every piece that was removable and sweaky clean... clean, clean.  We ran wire and soaked over night.   The change in jets helped lots but, now prefect starts, idles, pulls to 4.5k, get weak @ 5.2k and boggs, then when you back off, it jumps.
We rode 130 miles today in "INANE'S" back yard. From Littleton to Golden then up into the hills to over 9000 feet.  There was no noticable difference and the bike was consistant as above.  In 3rd gear as you roll it on with a moderate grade going 35 to 45+ it starts bogging and as you back off the throttle it surges ( a bit un-nerving in a tight curve).   It is absolutely consistant.

On the freeway in top gear on the flat, no problem to slowly get to 70 or 75, then as you hit and incline ( like where trucks are blinking there lights as they go up the incline "slow trucks 55")  the bike has no pull and it boggs, so down to 4th and run at 6K then slowly gain to 7k then shift to high then loose ground.

I am sure that some of this is altitude connected, but! not all of it.  It is just not accelerating right.  The exhausts are clean and clear.
Inane thinks the air cleaner is to "easy breathing" and he gave us an old used stock paper filter.  Rhpaw is going to try that.

The emulsion jet? is that the one the looks like a tube with many rows of small holes (8 or 10 @ 45degree spacing) with larger passages at the top. Fits flush between the top and bottom. Very clean.  And a clean POR15 tank, inline filter, new lines, etc,

One more trait... when warmed up and ready to go.  If you just grab a handful ( 3/4 twist ) quick.  Kinda like a good punch to the stomach.  You know what I mean.

We are ready to try anything.  Thank for your interest and help.

[inanecathode]

Yeah, i'd play around with the intake a bit, see if restricting it changes how it runs. It's acting very very very lean if its surging like that.

[akvision]

Inane!

Great hosting today. 8)  We  really enjoyed the guided tour of our back yard.   Great to get to know you and hope we can do it again..
maybe early Sept and think about the AK adventure in 2010.  I am going to do it, with a cooperative "V' or not.  We will first out try your suggestion and maybe others will weigh in. 

Can you add to my symtom discription?
akV

[inanecathode]

Hmm, it starts and idles fine, sudden throttle wackage off idle yields rough almost out of sync sounding revving. Along with extremely loud intake noise.

[rhpaw]

Inane..... your intake would sound like that too if you had quiet pipes.. ;)

[QBS]

Sounds like a vacume related issue in the secondary/main curcuit.  At slow roll on, your secondary curcuits either arn't getting any vacume or they are clogged and not getting any fuel.  Then when you back off, your primaries are apparrently kicking in a little to keep it running.

Your excellent idle and good starting rule out a problem in the primary area.  Reexamine your accell pump operation for both carbs as well as your flapper valve actuation.  Flapper can be tested by sucking on its vacume line and looking for flapper movement.

[inanecathode]

It'll stumble and sputter even if you roll on the throttle if its under high enough load. It's running just like if you're testing it with the air filter and box top off, when it'll run and idle ok it just doesnt like wot.

[supervision]

 Sounds just like my bike at elevation,  the more you open the throttle, the slower it goes!  Glad to here mines not the only one, that does it.  Hope to read about the fix, fer sure.  Easy thing to try would be take out the air filter, just to see if it makes it faster.  Or maybe first, the flaper adjust more open.

[funkamongus]

ah yes,,, I, too, have that problem,, Im at 6500 feet...

[Rick G]

I'm at 3500. Its OK at 5400 in Seligman , but at 6500 in Prescott it ran like shite , the last time I was up there in '05  . It hacked and snorted and was very disagreeable. When I got home to KIngman  it ran fine.

[QBS]

Couple of summers ago, I had my 83 two up, at 13500 ft(Rocky Mountain National Park).  Bike ran just like back home(55 ft above sea level, Houston TX) started fine, pulled evenly through the entire rev range.  Only problem was that it was putting out about 15 hp.

[Night Vision]

squeaky?

there are tiny holes in the bottom of ventris where the butterfly valves would be if closed.... did you clean them also?

you say you have the main jet sizes correct now..... what combination of air pilot jets do you have?

where are you at in terms of number of turns out on the pilot screws?

[funkamongus]

Good question Night,, I'll be looking for that answer too.. Small clues while I wait!!!

[akvision]

Like I said... clean, clean, clean, clean. I did not miss an hole, jet, orfice,all clean. Day light, air light.  Pressure blasted and carb cleaner galore.


jets front= 122.5
rear= 127.5
top jet is 130
Imulsion tube clean clean.
small tube jet  new and clean
we set the idle jets at  back at 3.5 to 4.0 out.
I think the front was at 3 or 3.5. 
Full chock 40 degree morning 5900 feet elevation three raps on the throttle and start with 2 clicks of the starter, runs at 1500 rpm.
Its sweet at idle and as it warms up climbs to 3 or 4 k and pull back choke to 1.5 k then when temp is 1/4 green choke off and away you go.... good  pull to +5k with slow even throttle.

I am thinking about picking up another set of carbs and rebuiding them myself then sending them down to rhpaw.  If we get it figured out then I will put them up for grabs here.

I suggested that rhpaw change out the plug wires to the new set he has and clean all the coil connections.  I agree with Inane that it is a carb problem..... rhpaw has carb flu right now and doesn't want to talk about it.

Hey, the way I look at it.  We have till September to bake and serve this one.   THE BIKE IS REALLY SWEET.  IT IS AS TIGHT AS YOU KNOW WHAT AND SO SMOOTH AND I LOVE THE PULSE, AND SOUND. 

[funkamongus]

Preach on, Brother Man!!!! I feel the same way,, Im letting this one slow cook until late fall when it will really come in handy to have a windshield and heater stuff, until then, no hurries,, Im gonna go through it with a fine toothed comb,, this site, too, and try to make her perfect by then... Polish all the aluminum, Paint all plastics and tins, stop all leaks, etc. Im running great except a small mid4 to 5k flat spot,, no dying threats, just no pull. If its the altitude, Ill get over it and limp off the hill to the valley for my riding pleasure!! Until then,, Im gonna try to turn her into the rolling sculpture she started out as, only better.