Air/ fuel mixture screws?

firefly

firefly

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What is the stock factory setting? how many turns out from a completely bottomed out position? I don't think they adjust them with an exhaust gas analyzer from the factory.

after installing the 4* advancer the bike is really performing very smooth & throttle snap issue is gone but I feel I can squeeze a little more power by slightly enriching the A/F mixture.
Any help greatly appreciated

Thanks
 
From the factory, I've seen them nearly completely closed to about 2 turns out. 2 1/2 to 3 1/2 is most common when jetting, except for Ivan's kit where he wants 4 1/2 to 5 turns out.

If you are completely stock and going to try changing the low speed screw settings, the carbs need to come out so you can remove the brass plugs covering the screws. As long as you are removing the carbs, you should put a jet kit in at that time. It's not a difficult job, but takes a few hours.

:)
 
jpgrfan said:
From the factory, I've seen them nearly completely closed to about 2 turns out. 2 1/2 to 3 1/2 is most common when jetting, except for Ivan's kit where he wants 4 1/2 to 5 turns out.

If you are completely stock and going to try changing the low speed screw settings, the carbs need to come out so you can remove the brass plugs covering the screws. As long as you are removing the carbs, you should put a jet kit in at that time. It's not a difficult job, but takes a few hours.

:)
Click to expand...

Is there a jet kit that just require needle & jet change ONLY with out drilling the slides and tampering with the air box?
Ivan's kit is out of question for me, RR involves airbox modification which I refuse to do, what else is available?
 
Factory Pro and Holeshot both have kits that are straight drop ins. Both work great. Or, you could do RavenRiders mods (thread on the other site) for about $20.

Dales (Holeshot) comes with jets, an advancer, and uses shims on the OEM neeedles.

The FP kit comes with replacement needles and jets. The kit is available with titanium needles (don't wear out), but I think that is a bit overkill.

Both kits come with new allen head screws for the float bowls.

RavenRiders mods calls for replacing the jets and shimming the stock needles Works great. You just have to order the jets (about $12 + shipping, or buy from a local MC shop).

Dynajet makes a kit, but, in the past it has not been a straight drop in.

:)
 
jpgrfan said:
Factory Pro and Holeshot both have kits that are straight drop ins. Both work great. Or, you could do RavenRiders mods (thread on the other site) for about $20.

Dales (Holeshot) comes with jets, an advancer, and uses shims on the OEM neeedles.

The FP kit comes with replacement needles and jets. The kit is available with titanium needles (don't wear out), but I think that is a bit overkill.

Both kits come with new allen head screws for the float bowls.

RavenRiders mods calls for replacing the jets and shimming the stock needles Works great. You just have to order the jets (about $12 + shipping, or buy from a local MC shop).

Dynajet makes a kit, but, in the past it has not been a straight drop in.

:)
Click to expand...

Great, thanks for the detailed response, I'll look into both Dale & RavenRider jetting & make up my mind, I am all for totally reversible mods in case I don't like them I can go back to stock setup again.
 
Dale's kit involves modifying the airbox as does RR's.
It is simple and you should do it. It really does improve performance with jetting.
The airbox top is a low cost part and is even available used sometimes, so it can be replaced if needed. It is simple to remove (you do it every time you replace the air filter).

:)
 
jpgrfan said:
Dale's kit involves modifying the airbox as does RR's.
It is simple and you should do it. It really does improve performance with jetting.
The airbox top is a low cost part and is even available used sometimes, so it can be replaced if needed. It is simple to remove (you do it every time you replace the air filter).

:)[/QUOTE

What exactly will the benefit be with jetting in my situation, I ride surface streets all day long 1st, 2nd & 3rd gear stop & go all day, I do take the bike on the freeway and get it up to 100mph in 6th but not frequently, most of the riding is 1 to 3rd gears.
I would like to fatten the low end as much as possible without creating a lot of unburnt gas/ emissions, my fuel millage with this kind of riding is 155 miles from topped full tank to steady fuel light after installing a 4* advancer.
I definitely don't need upper range speeds since I don't get in that rang often.

Thanks again for all your help
Click to expand...
 
firefly said:
What exactly will the benefit be with jetting in my situation, I ride surface streets all day long 1st, 2nd & 3rd gear stop & go all day, I do take the bike on the freeway and get it up to 100mph in 6th but not frequently, most of the riding is 1 to 3rd gears.
I would like to fatten the low end as much as possible without creating a lot of unburnt gas/ emissions, my fuel millage with this kind of riding is 155 miles from topped full tank to steady fuel light after installing a 4* advancer.
I definitely don't need upper range speeds since I don't get in that rang often.

Thanks again for all your help
Click to expand...

The airbox mod will help in the mid range and top end (4K rpm and up). It's free and just makes the bike feel better when you turn it up. It doesn't help much at 3K - 4K rpm's. MPG's may be very slightly (insignificantly) higher without the airbox mod. MPG is mostly a function of throttle applied. I get my highest MPG's when I'm running 55-60 mph (average) in the hills. Worse around town or at 70+ on the highway.
 
jpgrfan said:
Factory Pro
CRB-Y69-1.0
It has needles, jets, shims, allen head screws to replace the philips head screws in the bowls.

They have a few other nice items for the FZ1, too.

:)
Click to expand...

Thanks a million, I will order it, I like simple none destructive mods, as for the air box cover its cheap enough to replace.
when I get it & ready to put it in I will ask a few more questions.

Thanks again for all the help.
 
Factory pro Longer A/F mixure screws

With these longer screws can one reach by hand all 4 with carbs on the bike?
& avoid the 90* screwdriver?
Thanks again.
 
firefly said:
With these longer screws can one reach by hand all 4 with carbs on the bike?
& avoid the 90* screwdriver?
Thanks again.
Click to expand...

Does anyone have experience with these long air/ fuel mixture screws? can one reach by hand all 4 carbs to adjust them while the bike is running?

Thanks
 
firefly said:
Does anyone have experience with these long air/ fuel mixture screws? can one reach by hand all 4 carbs to adjust them while the bike is running?

Thanks
Click to expand...
I've never used them or seen them installed on a bike. I have made minor adjustments to mine a couple of times to try and get them set just right, but it wasn't really necessary. Once they are set, they almost never need to be changed. The recommended setting for the jet kits is 3 to 3 1/2 turns. I like 3 turns and sometimes 2 3/4 turns. That leave the bike a little bit cold natured at start up and it may take a couple of minutes of driving for the bike to reach operating temps and run perfectly smoothly. That is how it should be. If it runs nicely at start up, it will be a bit rich when good and warmed up. That can make for unnecessary popping from the exhaust on decel. Just set them at 3 turns and forget about them.

:)
 
jpgrfan said:
I've never used them or seen them installed on a bike. I have made minor adjustments to mine a couple of times to try and get them set just right, but it wasn't really necessary. Once they are set, they almost never need to be changed. The recommended setting for the jet kits is 3 to 3 1/2 turns. I like 3 turns and sometimes 2 3/4 turns. That leave the bike a little bit cold natured at start up and it may take a couple of minutes of driving for the bike to reach operating temps and run perfectly smoothly. That is how it should be. If it runs nicely at start up, it will be a bit rich when good and warmed up. That can make for unnecessary popping from the exhaust on decel. Just set them at 3 turns and forget about them.

:)
Click to expand...

Thanks again, I know a slightly lean when cold gets richer at operating temps while a rich cold setting gets richer & not crisp as it reaches operating temps, I'll just go with your recommendation of 3 to 2 3/4th turns when I install the FP kit.
 
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