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CommanderTalk.com
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Discussion Starter #1
Ok so for you carb tuning pros, here is what I have going on:

Idle = great
1/4 throttle = seems ok
1/2 throttle = seems ok
3/4 throttle = starts bogging and popping
WOT = popping, surging, loss of power

Any thoughts?
 

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180 Posts
I am no expert, but question....Did you change your main jets and how high did you go?? How many turns are your air screws out?? Air cleaner lid on or off. If you changed your mains and went above 150, make run with your lid off and see what happens. My V-force was very tempramental with tempertures and humidity changes. I could run in the afternoon fine, but after dark and had heavy dew, I had to put my lid back on or it backfired and bogged.
 

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CommanderTalk.com
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Discussion Starter #3
Well actually these main jets are not sized like normal jets. They are specific Dynajet needles and jets.

My mixture screw is actually backed out three full turns.

The intake does not have a lid, with the cover on or off, machine performed the same way.

I think, I am running a tad fat and that is what is causing the issue.
 

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CommanderTalk.com
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Discussion Starter #5
Just the intake thus far.

We anticipated that the kit may be off a tad, due to the fact that it is not specifically designed for an intake.

We are working with Dynojet on a kit, however, wanted to get some more insight.
 

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CommanderTalk.com
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Discussion Starter #7
You know I was thinking that, unfortunately, we are not sure exactly when we will be receiving the exhaust. Is this jetting is going to work for the exhaust, wonder if I should just leave it until then. No sense re-jetting if I do not have to.
 

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CommanderTalk.com
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Discussion Starter #10
If it is too rich (which it sounds like it) then the exhaust will (should) fix the problem.
That is kinda what I am thinking. Going to also wait to hear back from my contact at Dynajet to see what steps he wants me to take, since they are looking for feedback on their kit.

Got any pics of the intake install?
Yes, I will be putting up the intake install in the buildup area. I just need to get the page built :)
 

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CommanderTalk.com
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Discussion Starter #11
Ok after some discussion, we are thinking that the machine is actually running lean.

I am going to install some larger jets tonight and give it a run.

Then we will see about installing the new Dynatek CDI that came in today :)
 

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CommanderTalk.com
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Discussion Starter #12
We are getting there!

Idle = great
1/4 throttle = seems ok
1/2 throttle = seems ok
3/4 throttle = seems ok
WOT = little bit of popping, little popping when getting out of the gas.

Maybe a tad larger on the mains and we should have it.
 

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CommanderTalk.com
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Discussion Starter #14
Actually the jetting part is easy, the semi tough part is getting those carbs off.

You can leave the carbs joined together, however, you will need to remove the throttle cable (access this by removing the panel on the drivers side) You will also need to remove the various hoses from the carb as well as the choke cables (which are held on by brackets on the side and rear of the carbs. I can provide you with a disassembly sheet if it would help you.

What mods have you done that you are rejetting? With the open airbox design I am using, I am using a DJ150 main jet in the rear carb and a DJ146 main jet in the front. In addition, I am using Dynajet’s needles with the clip in the second position. Mixture screw is backed out three full turns from lightly seated. These main jet numbers do not correspond to the Keihin main jet numbers.

I am thinking I am still running a tad lean (where I live is approx 1400’ above sea level) so I am going to have to go another size larger…that should do it.
 

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I was just going to use the jetting that DJ says to use with airbox and spark arrestor out 134-138's..

On your setup im surprized that you are running a fatter jet up front rather than the rear,I think you need a bigger jet on the rear carb..

Any diagram will be a great help.. Thx..
 

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CommanderTalk.com
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Discussion Starter #16
My apologies, that was a typo...DJ150 in the rear carb, DJ146 in the front.

Sorry about that, previous post corrected.

Looks like Dynojet is going to sent me some DJ155 and DJ160 to try next. Is that does not work, then we will try the DJ165 and DJ170 that they are sending as well.
 

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CommanderTalk.com
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Discussion Starter #17
Well I am fat!!!

LOL, so we made a jump to DJ155 in the front and DJ160 in the rear, this was too much. Machine is definately running rich.

With that said, I wonder if I should keep it that way for now, seeing as the CDI and exhaust will be going in, which will lean it up some.
 

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CommanderTalk.com
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Discussion Starter #19
That is what the plan is...put the Dynatek ignition module in and while it helped a tad...it is still pretty rich!
 

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CommanderTalk.com
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Discussion Starter #20
Quck update, we are very close, if not just about right. Running the DJ155 in the front and the DJ160 in the rear.

How can I say this now when above I said how rich it was running. Here is why it was. The carbs have two metal pipes that enter them on either side, within this pipe is the choke cable. Each pipe is held on by two brackets, however, on mine one of the bolts must have come from the dealer and I never had to remove it the previous two times I was doing the jetting. The end result was the chose cable had backed its way out so I was literally driving with the choke wide open on one of the carbs.

Something to keep in mind when jetting :)
 
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