Re: same old jetting questions :(

[silverdevil]

How do you go about setting the sync ? everything I have read said to place a "SMALL DRILL BIT BELOW THE SLIDE AND ADJUST TO THAT: but I have not seen anywhere that said what size a "small" drill bit is.

 

[silverdevil]

You don't think I am going the wrong way do you ? rumming out of fule on the top and not going rich ?

 

[shawn kloker]

How do you go about setting the sync ? everything I have read said to place a "SMALL DRILL BIT BELOW THE SLIDE AND ADJUST TO THAT: but I have not seen anywhere that said what size a "small" drill bit is.

You have to take the carbs off,turn them over ,crank up th idle to where a drill bit can be slid under each slide.It doesn't matter what size drill bit,Just so all 4 are the same size opening.I sync mine with the motor not just a mechanical setting.

 

[shawn kloker]

You don't think I am going the wrong way do you ? rumming out of fule on the top and not going rich ?

Looking at the plugs should tell you if its lean or rich.

To check the main jets for real you have to get out on the highway,Haul *** full throttle for a while,then pull over immediately and pull the plugs to see how its burning.

 

[vmaxinID]

,Haul *** full throttle for a while,then pull over immediately and pull the plugs to see how its burning.

Hey Shawn,

Do you have to be in 5th to plug chop for mains?
Or can I do it in like 2nd or 3rd, at say like.....9500?

 

[maleko89]

Any gear between 7500 - 9500 rpms.

Mark
#1098

 

[shawn kloker]

It harder to do in the lower gears because it wants to redline and needs shifted to the next gear.I also like doing the high speed runs.

I guess you could try holding it at 9000 or so in third.100 or so mph.

 

[shawn kloker]

Hey Shawn,

Do you have to be in 5th to plug chop for mains?
Or can I do it in like 2nd or 3rd, at say like.....9500?

Shad,If your motor and carbs are stock and you have HMF pipes.152.5 or 155 mikuni mains are fine.What is your elevation.

All stock,I would leave the 152.5 mains in.I am just under 2000' here.I even ran 152.5 mains with stage 7 and it ran well.

Whats your complete setup?needles,jets etc. ?

 

[vmaxinID]

My prevoius problem with the hot surging has been remedied with a set of new plugs to get an accurate plug chop.
The old ones were to dirty to get a good reading. I was lean

When I bought the bike It had 2 FUBAR'ed A/F screws. I bought a whole carb instead of just the 2 jacked up ones, it came DJ stage 1.
I have a Cali bike so I didn't like the Cali carb anyway (emission tube, different jets)

So,

Elevation +-4,500ft Pocatello
Main jet 150
PAJ #1, and #2 stock
synched 2wice a month
needles out 2 1/2 (Paul's shim kit)
A/F screws out around 2ish, (all set according to plug color)
HMF 2D9S

It runs very well now, and no "hot surging" has occcured since the new plugs, and appropriate adjustments to the A/F screws.

This is where most of my summer riding takes place, they are all within 3 hours of my home.
So I need to keep it a bit on the rich side, I guess. :hmmm:

Jackson Hole 6,500ft,
Teton pass 8,431ft http://en.wikipedia.org/wiki/Teton_Pass,
Yellowstone NP +-8,000 ft,
"Since Yellowstone's elevation averages about 8000 feet (2400 m) above sea level,
visitors of any age may suffer from altitude sickness.
Minor symptoms, such as shortness of breath or loss of appetite, will usually disappear in a few days,
but more serious problems, including nosebleeds, muscle pain, nausea, or rapid heartbeat, should be treated.":ummm:





I was just wondering about the main jets plug chop cause I was doing it in 3rd gear.

It seems pretty hard for me to find a place to get into 5th, and full throttle around here, and hold it for a while....talk about YIKES!!! :rocket bike:

 

[silverdevil]

Few more questions for Shawn, from what I am gathering, you can't whack flat slides, so the WOT test is out at any speed, right ? I think that I read somewhere that you can normally kill the motor by doing that . You have ease into them, which when I do that it pulls pretty good and I really do mean ease into it, like very slowly.
It still falls out on that last 1/4,( that has to be the mains right ?) and the ability to not pull past 125mph, that feels like it is running out of fuel but maybe it is still just too rich when it has to depend entirely on the mains.
I currently am running 125's. going much below that is unheard of correct ?

 

[shawn kloker]

I can whack mine pretty good without hesitation.I changed the linkage point for my acceleration pump rod to get more of a squirt.I also just ordered one of those aftermarket pump covers which is supposed to also increase the fuel squirt to keep it from hesitateing.

What do your plugs look like?Mine hauls *** from the bottom clean through to the top end.Something is seriously wrong if 125mph is as far as you can get it wound out.

 

[silverdevil]

Needles are in the next to lowest slot, so one step from richest.

 

[silverdevil]

Ya, I think that It has gotten worse with the smaller main jets. It wound out more with the stock carbs.

 

[silverdevil]

I just moved the accelerator linkage too.

 

[silverdevil]

Probably the cleanest plugs I have ever seen. All four slightly grey porcelain still white.

 

[silverdevil]

OK, went up two positions with the clips and put a full set of 160's back in along with moving the accel pump linkage. Now pulls like a jet all the way to the rev-limiter and you can whack it all you want up to that 3/4 throttle and it was pulling all the way up 145mph when I had to get out of it, but that last 1/4 throttle is useless, it falls on its face anytime to try to use it. I just tried the 4000 rpm WOT and held it there. it acted like I hit the kill switch until you get back out of it. Then it jumps back to life wants to pull like you just lit the afterburners.

What does that tell anyone ????????

Is it has to be getting too much fuel right. am I going to have to go to something like a 85 ?:hmmm:

 

[maleko89]

Yep, main is too big.

Mark
#1098

 

[silverdevil]

It has done it on all of them all the way down to 125, so I am not sure where to go next.
Any ideas ?

 

[maleko89]

It's either your mains, fuel/float level, or throttle cables/linkages. I'm not familiar with flatslides so I don't know what size of mains to try.

Mark
#1098

 

[shawn kloker]

I would put the 140 mains in.Put the needles on the middle (4th) clip.Make sure the floats are all set at 9MM.Very easy on these.

Open the throttle and look at each slide through the stacks.All look good and open the same?

Maybye write down all of the other jet nubers.Big air,slow air,slow fuel and main fuel. There are 2 jets up by the stack and 2 in the bowl.

It sounds to me like the needles are too rich.

Did you try contacting Jon Cornell with your tuning issues?

I am not familiar with the Vgass set up, all though they are the same carbs as PCW , they are set up differently.

Don't be afraid to throw new plugs in either.They can foul easily with these carbs when out of tune.

A dyno might be your answer if all else fails.Then you will see proof of whats going on.


Write down the jets that are in there then we'll see.

My friend Rod is having his grand opening this weekend of Pro Chassie Cycle in Boardman Ohio so I am not going to be around much this weekend.I have been busy with this for a couple weeks.