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Discussion Starter #1
hi Guys
more questions from the land of chips with mayo on top
my 02 idles really smoothly even when cold
the tahitian blue is rough until its warm
i looked at mr haynes book and saw
the " way to balance the cold idle via the air valves "via m7 nuts
however
1 =>there seems to be no adjustment way/ screws for the butterflys ???
and
one needs to buy several m5 suction nipples to hook up the air flow meter
2 =>i see that the bike has one that serves to go the fpr unit, i guess that 3 more of the same can be used for the balancing???
3 => perhaps a dumb question why does a fpr which is positive pressure operated with spring bleed return need a vac line???? all that does is potentially drain leaked fuel into one cylinder??
cheers
pau
 

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Answers to follow
1. The BB's use an ir bleed to control synch for each cylinder. It's also how they create a high idle for cold starts. Basic principle give a cylinder more airflow it runs faster as long as you don't lean it out to far.
2. if you look you will see 4 hex head screws with Phillip's slots in them. These are direct ports to the intake tract below the throttle bodies. This is where you screw in the adapter tubes to read intake tract vacuum to balance them.
3. The FPR uses a spring that is setup to lift at a prescribed pressure. Limiting fuel rail pressure accordingly. Putting a vacuum feed on the spring side allows high engine vacuum to offset that spring pressure. This causes the rail pressure to drop at high vacuum situations, IE idle. The pressure drop reduces fuel pressure and volume in this case allowing the engine to idle leaner/cleaner. Honda's aren't the only ones using this design al lot of automotive systems do the same thing

Hope this helps explain everything
 
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Discussion Starter #3
Thanks mr Bees
Its getting clearer
So i understand
1
there is no butterfly adjustment
Just the 4 air valves
and
as i understand nr 3 is the base ??
2
the 4 vac ports are clear my question is can i use 3 more of the honda suction nipples for the other 3 ports that are not equipped as they are easily available and the ling ones are only in the states
3
the vac line on the fpr is now clear
If i want to balance all the ports in 1 shot can i just temporarily disconnect the vac line to the fpr to benefit from that ports reading ?
Thanks again
Paul
 

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Yes #3 is your fixed base.
If you can get 3 more nipples yes then you can. But just be careful they get very hot. And if you drop one of them or the plug screws they get stuck in the hardest places to find. Also be mindful the factory screws have small aluminum sealing washers that will drop off very easily. The screws themselves are very very short.
I would T that FPR line that way your less likely to load up the cylinders.
 

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Discussion Starter #5
Many thanks bees
Just did tge proceedure on 1 bike and idle much smoother
Hayes says to have a separate feed but as long as you dont have popeye forearms you can just lift and support the rear of the tank and access every thing
Curiously one bung bolt nr 4 was allen head the rest m8 head with posidrive cross
The alu wasers appeared to be cemented in place
I used 4 pce m5 nipple from my very old carbtune kit and used the rubbervtubingvto grip the nipple to guide and rotate in without dropping it
The actual balancing took about 3 minutes
As you said nr 3 has no nut and is thus fixed in position the other 3 are set to the same vac as nr 3
The overall cold start adjustment nut is hidden under the airbox and not accessable
I can smell fuel but see no leaks so i am going to change 21 yr old fpr preventatively before its a real issue

So just the rattly clutch to sort out
Question are the carb and efi friction plates interchangeable ??

Thanks again for the guidance
Paul
 

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Hah
Bet that Allen screw replaces one of the original ones that got dropped.

Yes the only difference I believe is the removed the jutter spring on the FI's and put in a friction if recall correctly. But don't quote me on that 😁. I do know the steels and frictions are the same for sure.
 

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Discussion Starter #7
Hi Bees if you mean the 5 rotary damper springs on the clutch basket when i took off the 2002 one it was fitted with the springs unless im auddenly having visions :)
 

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No the spring I am referring to is in the clutch pack stack. It's a flat wire spring that helps keep the plates from rattling in the basket itself
 
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