Jump to content

unbalanced ctlinder burn


jcshee

Recommended Posts

hey guys I have a 04 shee it is a 4 mil short rod v force4 reeds stock head and carbs fmf pipes. the problem I am having is the right cylinder is burning great the left is wet and fouling out compression test is the same about 125 cylinder leak down holds a 5 psi for 30 min carbs are jetted the same any sugestions

Edited by jcshee
Link to comment
Share on other sites

how does it run? Is it running on both  cylinders? check your spark,It could be the cap in the spark plug boot, or a coil going south.  Im guessing you have checked your main jet?? check your slide and needle, I had a needle causing a rich condition, it had worn grooves down the side. 

Link to comment
Share on other sites

the jets are both new on the mains and the needles are new as well. plugs are tight and it is still running the stock coil so the plugs have the screw on the top of them. it seems to run ok down low and in mid but when it gets the rpm up and you are in it hard it is like it hits a brick wall and just doesn't pull. both cylinders are firing good at idle and the right side seems to have a little more pop to the exhaust at idle then the left. I am thinking coil/wires as well

Link to comment
Share on other sites

That's tough to say but 300 to 340 sounds about right on the main, I would go up to 30 on the pilot and dial the air screws in from there. But I knowa at 125psi your not making enough cylinder pressure to get a complete burn on race fuel. Switch your fuel and go from there. It's going to run alot better on the correct fuel.

Link to comment
Share on other sites

Have you tried swapping the wires? to see if the issue changes sides?

 

What type of pipes are you running? are you sure they are free from obstructions and good silencer packing. Running super rich can cause them to get oil filled and block exhaust flow.

 

Did you change to the proper fuel octane, premium pump gas? Higher octane fuel requires more compression and timing to ignite properly. Using too high of an octane results in more unburnt fuel (see the above statement about your muffler packing)

 

are you running the airbox with the lid on? if so your jetting may be a little fat for that amount of airflow dependent on your temperature and altitude. Higher altitudes require smaller jets at 3200 ASL you would need smaller jets then a similar engine at a lower altitude,

 

As stated above your lean on the pilot. Vf4's especially need a larger pilot jet. your altitude may not require the usual 30 but possible a 27.5

 

Just for reference, what is your needle clip set at?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...