VMAX running rich, stage1 kit

[Eatshorts]

Hi
i purchased a VMAX, that had previously been set up with an aftermarket exhaust. Now the original is back on and its running a bit rich. Engine running cold and poor milage.
Should i return the original pilot air screws?

What main jet size would be recommended for kn filter with airbox mod, and original exhaust.

It runs ok at higher rpms when i open up the throttle.

http://www.dynojet.com/pdf/european/E4116.pdf


PS, should check the sync too, could anyone recommend a reasonably priced sync tool?
And does anyone know the partsnumber of the fuel mixture screw, one is a bit damaged.

Cheers

 

[Eatshorts]

Its set up with 165 main jet.

Any suggestion of which jet i should use? Have 152,5 / 160 as options.

 

[tugla]

For sure carb sync ( motion pro or Morgan carb tune tool )
Prob 150 will work as 152.5 are stock. You can put the stocks back in, check the sir fuel screws on how man turns out they are. Do you have the stock needles also?
While in there I'd check all the jets that they are stock.

 

[scuff]

if your stage 1 was the same as mine i.e. Dyno Jet Stage 1 (it should be) you will need to take off the side covers on your carbs and check your needles, springs and PAJ2 jets, my bike had the slides drilled Stage one springs and DJ PAJ2's so if you want to go back to stock which is do able with relatively low cost you will have to change all of that stuff or you could keep the aftermarket exhaust and go with Morley's Muscle Jet Kit, which is what I did, if you search on here you can find pic's and write up's in the Carb Tuning section that will help you determine just what you have and don't have Good Luck !

 

[sdt354]

Stage 1 needles, not the easiest to tune, will not work well with stock exhaust. Also, good chance the A/F screws are out too far.2- 2 1/2 turns out from lightly seated is average. Air jets should be put back to stock. +1 on #150 Mikuni mains. Drilled slides can be filled with epoxy and drilled to stock size.

 

[Traumahawk]

My recommendation is put all of the PAJ's back to stock, the springs back to stock, and main jets back to MK 150's. You can keep the needles, and put them on the 1st clip from the blunt end.

Dannymax sells the A/F screws. What dynojet calls the air jets, the yamaha factory manual calls primary air jets #2. Those are the ones behind the diaphragm covers.

If you dont know how to do something this forum can walk you thru ANYTHING. Plus, you will be a better mechanic for your bike, than taking it somewhere else.

 

[caseyjones955]

I'm at 3500' with a stock bike other than a Kerker 4-2-1 and K&N drop in filter.

My max was cursed with the Stage 1 kit when I bought it. The air jets were DJ150 and I know stock the MK170. With the stage one setup as the directions suggested it was grossly rich and it had a wicked stumble at around 4k. I went all the way down to a MK145 on the main jets to try and counter it which smoothed out performance but it's still intractably rich. I have learned here that the max likes to be a touch lean and even the OEM jetting is a hair rich, but the stage 1 is insanely rich. When you got your bike did you get any of the old OEM needles, springs and jets with it?

There are two sorts of jet sizes your going to become familiar with and this link explains the difference between MK (Mikkuni) and DJ (Dynajet). MK jets seem to be what the rest of the civilized world uses. Keep this for reference, your bound to need it before your all done.

http://vmaxoutlaw.com/tech/dyno-mikuni.htm

 

[Eatshorts]

Thanks guys, I'll start by getting a new af screw and the sync tool. Then i'll reinstall original jets.
The aftermarket exhaust is a short free flow set. It would be extremely noisy.

 

[Eatshorts]

How big of an impact does the drilled slide have?

 

[Traumahawk]

How big of an impact does the drilled slide have?

A drilled slide makes the needles react quicker.......and if its set up right will make the bike rev quicker. If its not set up right (like the stage 1 kit) it will contribute to being rich thru the midrange. Drilled slides WORK if your going to Seans muscle jet it, or a stage 7 kit. If your going back to mostly stock.....drilled slides dont work that well.

 

[Eatshorts]

What size is the original slide hole? I can order a dremel bit i guess and remake it.

And another issue i had was with the airbox boots, was a pain to get it back on the carbs. They where a bit short, like the rubber had dried out. Is there any solvents i can soak them in to restore them?

 

[blaxmax]

What size is the original slide hole? I can order a dremel bit i guess and remake it.

And another issue i had was with the airbox boots, was a pain to get it back on the carbs. They where a bit short, like the rubber had dried out. Is there any solvents i can soak them in to restore them?

I wrap them in a wet towel and microwave for 1 min-----twice

 

[Eatshorts]

I wrap them in a wet towel and microwave for 1 min-----twice

The whole airbox? Or are the rubber boots removable?


Sync tool ordered, and contacted dannymax about jets and af screws.

Just need to order a drillbit for the slidehole and I think I'm set. :biglaugh:
Any size suggestions?

Also checked out the jet swap and carb rebuilding threads. This forum is Gold.

 

[blaxmax]

Just the boots. You can use wd-40 also but then don't put them in the microwave.

 

[carrizog60]

usually at work i use a heat gun.
be careful and move the gun.always!

 

[caseyjones955]

I just removed the stage one PJ2s, they were the DJ150s included in the Stage 1 kit and replaced them with the MK170s that should have been there stock, thanks Eric for picking up on that! I put the stock springs back in with my undrilled slides, fit the MK147.5 mains (Were DJ170s when I got the bike) and OMFG this thing FLYS!! My vboost is not working for some reason but it still rips to redline with fury and passion. I now have midrange torque to spare in any gear from any RPM it just pulls with no hesitation or stumble, and a blinding top end is a thing now, even w/o the Vboost working.

It was drowning in that Stage 1 kit. I still have the stage one needles with the clip on the blunt end with no shims, I think I'll get some stage 7 needles just for good measure. Let me go on record as saying eff the stage 1. I should have snagged Morleys jet kit when I got the bike, I would have saved so much time and hassle.

 

[Traumahawk]

I just removed the stage one PJ2s, they were the DJ150s included in the Stage 1 kit and replaced them with the MK170s that should have been there stock, thanks Eric for picking up on that! I put the stock springs back in with my undrilled slides, fit the MK147.5 mains (Were DJ170s when I got the bike) and OMFG this thing FLYS!! My vboost is not working for some reason but it still rips to redline with fury and passion. I now have midrange torque to spare in any gear from any RPM it just pulls with no hesitation or stumble, and a blinding top end is a thing now, even w/o the Vboost working.

It was drowning in that Stage 1 kit. I still have the stage one needles with the clip on the blunt end with no shims, I think I'll get some stage 7 needles just for good measure. Let me go on record as saying eff the stage 1. I should have snagged Morleys jet kit when I got the bike, I would have saved so much time and hassle.

Good, glad its better. Thats how a Vmax is SUPPOSED to run. It is supposed to put a smile on your face every single time that you ride it.

 

[caseyjones955]

I'm smillin' now for damn sure!

Now looking for a great thread I saw on troubleshooting Vboost systems, it seems dead now, before it was working intermittently. I should add that I noticed this first after installing the COPS so maybe related, dunno yet.

I'll have to have a chat w/Sean and see what he has that might replace the stage 1 needles and maybe get my hands on one of those airbox lids. It feels great to finally have it match the stories I hear.

 

[caseyjones955]

Update. Long ride today through Custer, Iron Mtn road, and WY et al.

I turned the AF screws out another .25 turn so I'm at 2.75 for fronts and 3.25 rears and its solid, no more queefing of softness. It's spot on and pulls violently to redline. In fact a shift light is in my future, it sweeps past 9k so damn fast. The biggest change was putting a stock size PAJ2 and stock springs back in, it's not even the same bike anymore.

I had to switch to RES at 90 mi before. Today I hit 111 mi on the 2nd fill up with no fuel light, fueled up 2.6 gal so roughly 42.7 mpg, a cross of 65-75 mph open highway, hills, twisties, scenic byways and a few VERY spirited passes, elevations between 3200' and ~6500', it's pretty lofty around Crazy Horse.

The aroma of the pines stretching into WY and back through Custer and back up around the park, simply amazing. There are very very few RVs or HDs in the way as of yet, its perfect. I'll be doing some retuning when Morleys kit arrives in the mail but to have it this damn close is sure encouraging after struggling with the Stage 1 for so long. All and all a blissful day! :eusa_dance:

http://www.ironmountainroad.com/

 

[blaxmax]

^Good news