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Discussion Starter #1
Hello wakasaki members, got 2 questions

I want first to buy and K&N filter and i wonder if i must syncronize the carburetors again and if the fuel consumption will rise

Second i want to buy a factory pro jet kit, here i suppose it will need syncronization and again the question about fuel consumption

If i buy only the air filter will be any differences ?

thank you.
 

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If you install a high flow air filter (k&n) you will most likely need to re-jet the carbs. More air requires more fuel if you don't re-jet you risk leaning the engine out witch is very bad and can cause serious damage.
 

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If you gonna go with air filters, and you want to run a jet kit, might as well toss a full exhaust on there while you're at it to really open her up and let her breathe good. Yes, you will want to resync the carbs, but you will also want to set the trims and shit too. Take it in and have it set up, or do it sniffing the exhaust pipe like the old timers used to...:lol:
 

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Hello, dns. How are you?

First, regarding K & N filters. They save you money because you can clean them and re-use them. However, they do NOT increase air flow. Why do I say this? I own a BMW M6 (car). I belong to the local chapter of the BMW CCA. Every year we have a dynomometer clinic in Kirkland. One year, a guy with an M5 put his stock air filter on his car, ran a dyno test. Got the chart with torque and horsepower curves. Then he installed his special K & N filter. Ran the dyno again, and the curves were IDENTICAL. So, buy the K & N because it is a better filter for re-using it and for overall clean filtering, and because it filters smaller particles. But do not buy it to increase air flow because it simply does not do it.

Second, regarding synchronizing the carburetors. If the motorcycle engine is running fine right now, do NOT try to re-sych them. Carburetors only on rare occasions require re-synchronizing. Such as if you removed them and actually separated them, which is not recommended. You can clean and jet the carbs without separating them. If you simply wish to check your carburetors to see if they in fact are properly synched, then that is your decision if you have the correct device to do it. Changing the air filter does not affect the synchronization.

Third, regarding re-jetting. My experience with re-jetting is that it is probably necessary if you were to replace the exhaust system with something that is less restrictive. Operative word is "probably". Not "absolutely" or "must". Changing the air filter does not affect jetting. If you were to install a turbo, change the camshafts, or dramatically modify the air box from its engineered specifications, then probably you have to change jetting. But not with merely an air filter swap.

The only way to determine which jets you need is to have a shop with a dynomometer check first with the existing system on the bike, then make your modifications and then check again, and tune as necessary from there. Maybe you need more rich jets, but you may need leaner jets. Simply guessing and putting some in is a poor way to tune the bike and you are best off leaving in the stock jetting.

I own a Kawasaki ZR-1100 Zephyr. I bought a Vance and Hines 4 into 1 exhaust system for that bike after discussing it with one of their technicians. He told me if I buy their jet kit for that bike, the exhuast system will increase my torque and horsepower. I had a shop with a dyno install everything and use the dyno to tune it. No matter what they did, the system produced LESS horsepower and torque. Even when they removed the baffle and had it wide open in the muffler. So I don't believe any company when they say you get more horsepower, and when the Harley riders put on their loud pipes, I just laugh because they probably just made their bike slower (and horribly loud). That bike has had the block bored out and has custom blue printed sleeves and pistons and a custom made head gasket, to increase the displacement to 1322 cc. It has way more power and I am using the Vance and Hines jets that I mentioned above, with the stock exhaust system, and it runs smooth as butter, just like it did before the race shop modified the motor. The guy who did the work felt that the existing jets with the stock air box and stock exhaust worked fine.
 

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Discussion Starter #6
After i installed the sport filter it smells a little fuel from exaust(i am not verry sure), and only sometimes it's choking under 3-4k rpm but i think is from the old fuel from last year.
Everything was changed:fuel filter,air filter,oil,antifreeze luquid.
The bike have an leo vince carbon exaust installed 3 yers ago.
 
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