Tuning Help

Advertise with us
shop deals on amazon
Shop deals on ebay
VMAX Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
1st Shirt Maxer

1st Shirt Maxer

Well-Known Member
Joined
Aug 7, 2012
Messages
342
Reaction score
1
Location
Enid Oklahoma
After doing some work on the bike I pulled the plugs to find all 4 look like the one in the picture. I have supertrapp slip-ons with the open end cap, I'm running a k&n filter with stock carbs except the mains were stepped down from 152 to 147.5. Any ideas why I am so rich? Forgot to mention my a/f screws were set at 2 turns out from all the way in.
 

Attachments

  • IMG_20150326_204614.jpg
    IMG_20150326_204614.jpg
    30.6 KB · Views: 75
What Needles are you running.
I have Supertrapps with all Stock jetting and un-shimmed stock needles with a K&N Filter and my plugs are all tan.
I run the open caps most of the time and only put on the closed caps (with 8 discs) when I'm doing group rides.
 

Attachments

  • Vmax_Spark_Plug_Color.jpg
    Vmax_Spark_Plug_Color.jpg
    18.8 KB · Views: 31
I'm running stock needles the best I can tell. I bought the bike in Guam and it was a barn find in poor condition. Ill pull a needle and measure it tomorrow and see if it is stock.
 
Eric makes a good point also, your floats could be set way too rich.
And look at the Pictures below to see what the different needles look like.
Stage 1 or Stage 7 needles will cause a Max with slip-ons or stock exhaust to run too rich.
PS
The Canadian Bikes have needles shaped like US Stock needles but with slots like a Stage 1 or 7 needle which allows them to be easily adjusted.
 

Attachments

  • VMax_needles-Stock-Stg1-Stg7.jpg
    VMax_needles-Stock-Stg1-Stg7.jpg
    53.3 KB · Views: 37
  • VMax_needles-Stock-Stg1-Stg7-FP.jpg
    VMax_needles-Stock-Stg1-Stg7-FP.jpg
    38.9 KB · Views: 28
The plug will indicate what to mixture was just before you turned the motor off.
For example, if you had just switched off immediately after a full throttle run they would look different from if it had just started on choke.

Before tearing the carbs apart then, if not done, suggest you do a plug chop. Motor should be at operating temperature (run under load for ten miles or so) taken to (say) 4K for several seconds then hit the kill switch.
Remove a plug which will indicate the mixture @ 4K.

From your photo you can't tell if the black is sooty or oily which makes a difference as to which direction you go.

One last thought, you had turned the choke off or confirmed that the plungers all seat correctly?
 
Update, checked my needles and they are of the stock variety. My wet float height is spot on 3 of the 4 carbs, one of the drain tubes has been broken off and I don't know how to replace it. I took it out today and could tell it was way rich. I turned the a/f screw out 1/2 turn on each and she ran better. I will look at the plugs tomorrow and see what they look like. Thanks for all the help
 
If you have a carb sync hook it up and start with carb #2 with the idle at 1200 rpm.
Run the a/f screw all the way in easy and back it out until it reaches it highest vacuum, (probably 2 1/2 to 3 1/2) then go to # 4 next and do the same thing- then #1 and then #3. You setting your a/f mixtures to highest vacuum no matter what altitude you are at.
Then sync the carbs.
 
You must log in or register to reply here.

Similar threads

Spyglass
Carb Tuning
Replies
5
Views
696
Zeus36
Zeus36
K
Kerker or Supertrapp slip-ons? Help me decide
Replies
10
Views
966
wilks
wilks
I
Carburetor Help
Replies
13
Views
1K
Woody
Woody
Straka
Help Carb Sync
Replies
16
Views
814
Fire-medic
Fire-medic
Cyrotronix
Should I change my main Jet?
2
Replies
39
Views
3K
Fire-medic
Fire-medic

Latest posts

Back
Top