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Discussion Starter #1
So I'm still having some issues with the jetting on my bike, and was wondering what everyone else is running. It's driving me nuts...

My mods/settings:

Yosh TRS slip-on
Ivan's jet kit
OEM & K&N air filters

Going from memory, but I think my needle clips are on the second notch, and my mixture screws are 2.75 turns out. Carbs have been synched, and I haven't checked my float levels.

Elevation is pretty close to sea level (Halifax, Nova Scotia, Canada).


My issue is around 8000-9000 RPM, the bike feels like one or two cylinders miss temporarily. Power is reduced, and she sputters until she turns up a bit higher. I've tried running the mixture screws out to 3.25 turns out, and I've tried swapping my K&N filter for an OEM, and neither seems to fix the issue. If anything it currently runs better with the K&N, but not by a lot. It runs pretty well everywhere else in the RPM range, but 8-9K is a horrible spot to have a power loss.

Suggestions? Needles? Check the floats? Change the mixture? I haven't pulled the plugs recently, should I do so?

Cheers!
 

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CCS #164
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404 Posts
I was gonna post a thread similar to this but i forgot lol. hopefully we get a lot of people replying so this could be a first gen carb database. instead of power commander maps this is what we have...

anyway here are my mods:
Leo Vince slipon
Factory Pro 1.0 jet kit (with 152/148 main jets and stock pilot)
airbox modified (restrictor cut out, and the only air entering the box is from the air ducts up front and the side carb hoses.)
YEC pressurized float bowl clone mod

My jet kit settings are:
needles at the 5th notch, mixture screws at 3.5. float height set to 1mm higher. carbs synched about a week ago.

It was running very lean (plugs were white and there was surging at certain RPMs) so i raised the float level a bit which made it run much smoother. I still have a little tuning to do because I dont believe the needles should be on the 5th notch...

As for your problem Rad33, try lowering the clips on the needles so it runs a little richer. 8-9k is part of the RPM range that the needles heavily affect. Also if you pull your plugs and look at the color of the carbon buildup, it will give a good indication of how rich/lean your engine is running.
 

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Still workin the bugs outta mine too.. It runs like a raped date at WOT all the way to the rev limiter. Breaks up a hair at part throttle when maintaining speed, and around 8k, I get a nice surge of power, and burping the gas shows a mild hesitation below 9k.

Motox is right, you should try to richen your needles.

My setup:
02 R6
HR1 Riot slip on running the baffle wide open
Factory Pro Velocity stacks
OEM air filter
Factory Pro 1.1Ti jet kit

Pilot screws 3.5 turns out
Needle clips are on the 3rd line from the top of the needle.
1100 Ft above sea level
Carbs never synch'd. Floats left as is.
 

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CCS #164
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404 Posts
Still workin the bugs outta mine too.. It runs like a raped date at WOT all the way to the rev limiter. Breaks up a hair at part throttle when maintaining speed, and around 8k, I get a nice surge of power, and burping the gas shows a mild hesitation below 9k.
Sounds just like my bike. Is it even possible to get a carbed bike to run well at low rpm/part throttle AND run very well at wide open throttle? Its like its either one or the other from what i've noticed :confused:
 

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Parts Pimp
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Sounds just like my bike. Is it even possible to get a carbed bike to run well at low rpm/part throttle AND run very well at wide open throttle? Its like its either one or the other from what i've noticed :confused:
Hahahaaha I'll let you know. I will definitely get it perfect with a little more effort. Personally, I think the real problem is us putting in these jet kits. None of em come with pilot jets, the needles have play in them, they dont sit nicely like the stock ones with the big cap at the top.

If I can't get it nice after adjusting the needles and going way rich on the pilot adjusters, I am going to order different pilot jets. I think there is only so far you can go by adjusting the screw. And then I'll go back to factory needles but will shim them up for finer adjust-ability. A guy who owns a reputable shop by me has told me a few times that the stock needles with shims are the only way to go.
 

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Discussion Starter #6
So I finally got around to pulling the plugs today. If anything, I'd say it looks like I'm running rich. All four plugs looked identical. Not the nice tan color I'd like to see, and not white-ish indicating running lean, but slightly darker/sooty color. Still figure I should try going a bit richer on the needles?
 

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So I finally got around to pulling the plugs today. If anything, I'd say it looks like I'm running rich. All four plugs looked identical. Not the nice tan color I'd like to see, and not white-ish indicating running lean, but slightly darker/sooty color. Still figure I should try going a bit richer on the needles?
It's hard to say. I would try going riche on the needles cause I feel like the bog is aused by that. Lookin at the plugs is a good way to see overall perormance/mixture.

The plug would really indicate your main jetting setting. Since that's what the bike really sees.

with the factory pro kit the guy from factory pro said their needles seem to be rich, but you have the ivans. Despite what the factory pro guys said I'm gonna try and go richer. I'm 1 clip from as lean as possible now
 

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Shooo Sheff
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882 Posts
Looks like Im not the only person trying to figure this out haha

Full akro system
BMC highflow
Factory pro jet

2.5 out and clip on 5th down from top. It runs great 8K+ but bottom seems like it can do some work, occasional bog and crummy start from stop. just replaced plugs and the old one seems rich, carbon build up and one of them seems wet a bit, not too much. Im gonna try to move to fourth clip and see how it runs tomorrow.
 

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Looks like Im not the only person trying to figure this out haha

Full akro system
BMC highflow
Factory pro jet

2.5 out and clip on 5th down from top. It runs great 8K+ but bottom seems like it can do some work, occasional bog and crummy start from stop. just replaced plugs and the old one seems rich, carbon build up and one of them seems wet a bit, not too much. Im gonna try to move to fourth clip and see how it runs tomorrow.
Let us know. I was thinking 5th clip?! Really? That's really rich, but with the BMC that just may be how it needs to be. How's it run with the BMC? I am finding my bike is running lean when it's cold out. I guess different/larger main jets before the fall comes..
 

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Shooo Sheff
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So with the 4th clip it feels a bit dif but not by much around the mid. I guess it'll save me some MPGs. I found out 2 of my float needle were just not good and leaking fuel slooowly and I cleaned it up a bit and it has gotten better. Last week I opened the carb and looked to find pools of gas on top of the valve. The idle is better, no more hanging before dropping. Doing the blip test now show signs of being lean at idle so im gonna try and do 3 turns out and see how it goes. My exhaust decided to snap off at the collector too so its loud and I loosing power. Sounds great and runs like a mad man in high RPM though haha.
 

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So with the 4th clip it feels a bit dif but not by much around the mid. I guess it'll save me some MPGs. I found out 2 of my float needle were just not good and leaking fuel slooowly and I cleaned it up a bit and it has gotten better. Last week I opened the carb and looked to find pools of gas on top of the valve. The idle is better, no more hanging before dropping. Doing the blip test now show signs of being lean at idle so im gonna try and do 3 turns out and see how it goes. My exhaust decided to snap off at the collector too so its loud and I loosing power. Sounds great and runs like a mad man in high RPM though haha.
3 turns seems to be the best bet. I wanna get bigger pilot jets. I don't think it will ever be smooth or perfect without a bigger jet. There's only so much turning the screw can do
 

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Shooo Sheff
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I was wondering if running in cold weather will lean our bike out, like 60F. with windchill it must be like 50 something. I was running awesome this morning when it was nice and 80 out but on the way home from work it was 60 and it started to bog and lean pop from 3-7k rpm. works normal during WOT, maybe I should lower the needle back to 5...
 

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CCS #164
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404 Posts
yeah it will definitely lean the bike out. thats why carbs suck because they need tuning for significant changes in temperature
 

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Big ol pile of them bones
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Need Help!
Recently aquired 01' CLE R6
Has shortened Yoshi TRS(has to be off a suzuki(4bolt connection to mid pipe))
K&N Filter
New plugs
Just put Factory Pro 1.1Ti in it
Screws 3 out
Needles on 3rd clip
Would set floats if I knew what Factory height was.
Runs like GARBAGE between 4&8k(spit, sputters, surges, stumbles)
Above 8k runs great, pulls like a banshee to redline.

Any thoughts would be greatly appreciated.
Oh yeah, I'm @ sea level (Florida)
 

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Big ol pile of them bones
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Big ol pile of them bones
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Thanks for the info. Guess no one knows the float measurement from the carb surface? I'll have to make a gauge to check the way it shows in the manual.
Ok, i found out what was killing me. 2 of the 4 pilot jets were restricted. After a thorough cleaning :nocontrol.
Final settings (til I get a chance to get her on a Dyno):
1- Pilot screw out 3.5(recommended max in the kit instructions is 5(think I
would go up 1 size before going 5 turns))
2- Pilot Jets stock 38
3- Needle clip #4
4- Main Jets 155 1-4, 152 2-3
5- Floats??? Close to stock as i can guage using a piece of hose with a
syringe used for measuring baby medicine.

Runs almost perfect. Still a little weak around 8k but liveable, everywhere else is smooth and strong :toocool:!

Thanks for the advice x0ny!
 

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Big ol pile of them bones
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Thanks for the info. Guess no one knows the float measurement from the carb surface? I'll have to make a gauge to check the way it shows in the manual.
Ok, i found out what was killing me. 2 of the 4 pilot jets were restricted. After a thorough cleaning :nocontrol.
Final settings (til I get a chance to get her on a Dyno):
1- Pilot screw out 3.5(recommended max in the kit instructions is 5(think I
would go up 1 size before going 5 turns))
2- Pilot Jets stock 38
3- Needle clip #4
4- Main Jets 155 1-4, 150 2-3
5- Floats??? Close to stock as i can guage using a piece of hose with a
syringe used for measuring baby medicine.

Runs almost perfect. Still a little weak around 8k but liveable, everywhere else is smooth and strong :toocool:!

Thanks for the advice x0ny!
One more note. The needles that came with the Factory Pro kit were loose and bouncing around. Put a couple of those tiny washers that came with the kit on top of them and replaced the needle retainer. Not loose any more :D
 

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One more note. The needles that came with the Factory Pro kit were loose and bouncing around. Put a couple of those tiny washers that came with the kit on top of them and replaced the needle retainer. Not loose any more :D
WErd. I'm gonna give this a go. And by replaced the needle retainer, are you talking about the c clip on the needle, or the green piece that clips on and holds the needle in place?

When you say 4th clip for the needle, is that the 4th clip down from the top of the needle as it sits in the carb?
 

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Big ol pile of them bones
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WErd. I'm gonna give this a go. And by replaced the needle retainer, are you talking about the c clip on the needle, or the green piece that clips on and holds the needle in place?

When you say 4th clip for the needle, is that the 4th clip down from the top of the needle as it sits in the carb?
Retainer= green peice
4th clip position= 4th down
Keep me posted how this works for you.
 
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