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Discussion Starter #1
I just received my Yoshimura TRS street slip on, and I check the Yoshimura website if the bike needs any adjustment or tune up, since it'll be exhaling differently now. They suggested, "it is important to at least adjust the pilot mixture screws and shim the needles 0.5-1.0mm..." for slip-ons. Now how exactly would I know it's tuned to meet the requirements of the exhaust, how would I measure the calibration ? I am trying not to get the bike to run too rich or too lean, in fact, I like the current state of lean flow. Thanks.
 

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That's why you pay seasoned carb tuners like me to work on your bike.

ANYBODY can install a jet kit etc... Very few can actually tune one optimally. You have to have a certain level of knowledge for how each fuel circuit flows into the next one & at what rpms throttle positions it occurs. Most of it comes from experience & even with a dyno to give you accurate A/F ratios it is still a time consuming & sometimes complicated process to do it correctly.
 

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Short hijack, sorry Z.

So if I get a Micron slip-on for my bike (I know there not great, but its the best one of the 4 made for my bike that I can afford) I need to get the fuel/air mix adjusted again?

Thanks,
Sepias
 

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Every bike regardless of whether it is carb'd or Fi & even with a stock exhaust needs the fueling altered to be optimal. Changing the exhaust only makes it that much worse & in more need of being corrected in almost all cases.
 

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Discussion Starter #6
Lord Duckhunter said:
That's why you pay seasoned carb tuners like me to work on your bike.

ANYBODY can install a jet kit etc... Very few can actually tune one optimally. You have to have a certain level of knowledge for how each fuel circuit flows into the next one & at what rpms throttle positions it occurs. Most of it comes from experience & even with a dyno to give you accurate A/F ratios it is still a time consuming & sometimes complicated process to do it correctly.
HAHA, sure, can you make a trip down south? :D

I am not interested in putting jet kit, it is a slip on - one of the reasons I didn't want to get full exhaust is to avoid jet kits. I just need adjust the carb mixture screws enough to match the new exhaust. Job isn't difficult, but just getting it right and to measure the difference. Would I need carbs synchronizer for it, or is there educated guesswork to figure it out?
 

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Just doing the mixture screws themselves is pretty easy. First thing is to make sure you have the proper tool to do them. Many Keihin carbs have a special D-shaped tool that fits the screw head. First you turn them all the way in & count the exact turns on each screw until they are fully (BUT LIGHTLY) seated. might be 1 full turn or 2.5 turns etc...

Depending onwhere they were to start with you'll probably end up turning them back out at least one full turn past that point. When done properly you will probablyhave to reset the idle a little bit to get the rpms back down to the proper idle speed when you are done. The good news is you'd be pretty hard pressed to screw anything up just messing with the idle screws as they could always be reset back to stock & you can start over if you have too
 

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Discussion Starter #8
Right, thanks, I understand. What's still lingering is would turning the screws make any difference? How do I know that I'm getting the results I need? Or could I just leave them as they are? As you said they may raise the idle a bit, but same could be done with the stock exhausts on. Thanks again.
 

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It's kind of a tricky thing, cause you have to listen to & feel the motor to get it right. You are basically looking for a good healthy lope to the motor without it being a fast idle kind of thing...

There is a pretty wide range of adjustment on the screws that will work for you even if not optimal, but if you go to far one way or the other then you will start to notice problems like hesitation at very small throttle openings, or a miss when you blip the throttle or even a strange dip in power when you upshift through the gears just as you crack the throttle back open etc... If anything weird starts to happen at very small throttle positions then you've probably gone too far on the adjustments

Oh & also stay away from K&N air filters on that bike!
 

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Whats wrong with K&N filters? I dont have them in my bike, but everyone seems to hate them and I'm curious as to why.

Sepias
 

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So your vote is OEM filters, even with out a jet kit or FI system?

Sepias
 

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Simply put you will never go wrong with OEM filters.

Sometimes aftermarket high flow filters do work & offer appreciable gains, most of the time they hurt the performance more than the help it.
 

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Discussion Starter #14
Yeah, my wallet wouldn't justify paying $50-70 bucks for an air filter, which wouldn't last as long, and isn't as efficient doing its job- filtering. :D

I am more of a mpg = performance guy, that's why I didn't even go for aftermarkets gearing to save some gas. No doubt it would also throw off speedo inaccuracy even more.

I had a jetkit and full vance & hines exhaust installed in my old FZR, a monkey must have done it. Because the bike was horrible to start, and after 1/2 hour of choke and throttle, it would sip fuel like gatorade while riding. Even having it as a first bike, I could feel in fact it made the bike slower. The bike was asthmatic constantly.

After I got my SV and F4, I never once had to use choke.
 

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There is some science & art to installing a jet-kit properly.

However a properly jetted bike will be a tad bit cold natured at first. As the engine temp gets hotter the A/F ratio gets richer so you jet them to run properly at normal operating engine temp. This means that when the bike is cold it will be a little on the lean side & requires the use of the choke to get it started & then as the engine comes up to proper temp the leaness goes away & the mixture richens up to where it should be optimally.

But as you described if you don't do it right it just makes things very sluggish or causes hesitations etc...
 

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My bike loves the gas to and hates mornings. It took me 15 minutes to get the idle right this morning and it hated the choke. Hopefully my V&H is the problem with my bike, its being replaced very shortly with either an Akra(fingers crossed) or a Micron(any opinions on microns?). I've never paid more than $25 for my air filters so I'm guessing their either a really cheap aftermarket, or since they were put in by a guy who drag races bikes constantly, its the OEM.

Sepias
 

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Discussion Starter #17
Does your bike have full system exhaust and jet kit as well? Airfilters cost about $25.00 for my bike through bikebandit.com or local dealer. Air filter for older bike should be cheaper, for example, for my '90 FZR600, it was $10-15.
 

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I haven't jetted my bike, I've thought about it but haven't done it. I still have the stock headers and a crappy slip on. I'm trying to figure out if the 89-96 FZR1000 will fit my bike since the V&H manufacturers part numbers are the same.

Sepias
 
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