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Trying to get FCR tuned - Pop on decel, Roll-on bog, etc.

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Just got back from a late night brap through the city to test the fruits of my labor.

 

Before I get into it, i'll list the specs:  DRZ 434, Yoshimura RS2 Comp exhaust, 3x3 mod, FCR-MX carb (160 main jet, 45 pilot, 100 air pilot, EMN Needle @ 3rd notch, F/A at 3 1/4th turns, o-ring mod)

 

Bike runs really great except for a few concerns:

 

  1. If you're in 5th gear and drop the throttle (not even hard, but say you're slowing down ) and roll back on, there's a slight pop then a surge- kind of jarring.
  2. On deceleration, it pops. I know- it's sometimes normal. 
  3. The throttle response doesn't feel as quick and snappy as it could be.
  4. When launching, it bogs every so often then then surge, sort of like the 5th gear roll-off issue.
  5. Misc stutters when cruising

I'm also curious about the fuel pump timing screw under the throttle wheel. I had to take it out when readjusting and i'm not sure if it's properly adjusted. The factory timing marks are worn off from me manhandling it yesterday, so i went off of a picture where i saw 2-3 threads poking out. Would this cause some of the aforementioned issues?

 

Thanks in advance.

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Ok, so you have messed with the AP screw...I don't understand why, but that don't matter now....

Turn the AP screw fully in then back it out 2 and 3/4 turns...This will be damn close to the setting point...

Is the carb from the TT store..?... If yes , remove the pilot air jet..

Replace the 160 main jet with a 155...

Is the stutter better with the air box door removed.??...If yes install an OCEMP needle, clip 3

Fine tune the fuel screw with this procedure ....http://www.thumperta...ad.php?t=327405

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Ok, so you have messed with the AP screw...I don't understand why, but that don't matter now....

Turn the AP screw fully in then back it out 2 and 3/4 turns...This will be damn close to the setting point...

Is the carb from the TT store..?... If yes , remove the pilot air jet..

Replace the 160 main jet with a 155...

Is the stutter better with the air box door removed.??...If yes install an OCEMP needle, clip 3

Fine tune the fuel screw with this procedure ....http://www.thumperta...ad.php?t=327405

 

Long story- but in a nutshell, had to back it out to reset the wheel position. So just bed it in and back it out again?

 

Pilot air jet is removed.

 

I'll keep tweaking based on your suggestions - thanks  :ride:

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Turn the AP screw fully in then back it out 2 and 3/4 turns...This will be damn close to the setting point...

 

I noticed a similar problem when I was out testing my FCR.

Pardon the ignorance but what/where is the AP screw?

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I noticed a similar problem when I was out testing my FCR.

Pardon the ignorance but what/where is the AP screw?

Accelerator pump.

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I noticed a similar problem when I was out testing my FCR.

Pardon the ignorance but what/where is the AP screw?

 

De screw with green paint mate...... :thumbsup:

 

 

 

FCRO-Ring3.jpg?t=1302429145

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