Hello guys

 

Ive recently installed the k&n air filter + the scorpion gp slipon on my z800

 

Now i've noticed that the bike has having more difficulties reaching its top speed (goes to 202km/h and doesnt want to go up anymore). We have a 7km Straight 8 Lane High way here where i unleash my bike at night sometimes when i pass by. Could this be because of the Air filter ? Would i need perhaps a remap or something ?

 

bike has 1300 km so far (only started to push it after 600 km)

 

If so i'd rather take it off and install the stock again since there is no workshop around my town/city that does this.

 

 

Yeah well when you mess about with things the oem ECU may not want to keep up with you.

I suspect the same, too much airflow for the ecu to handle.
Put the stock filter back and see what happens, then you will know for sure.
Actually let us know, curious now.

I will visit the kawa dealer tomorrow and ask for the stock filter and exchange it. then going for a top speed run again and let you know

 

This is the filter i've bought

 

http://k-speed.net/product.detail_1020433_th_5989513

 

 

Yeah well when you mess about with things the oem ECU may not want to keep up with you.

thats what you did with your vigo then had to sell it,ha.

still alive then ? how is the old city.

 

Changing the stock air filter isn't always beneficial, especially without altering your fueling. As others have mentioned, it seems like it's a poor choice for your bike with making some changes (it's the same for my Kawasaki- others have found a power decrease when swapping the filter without adding fuel).

Now i've noticed that the bike has having more difficulties reaching its top speed (goes to 202km/h and doesnt want to go up anymore)

 

 

 

Just curious but what speeds did you attain before the filter change?

Changing the stock air filter isn't always beneficial, especially without altering your fueling. As others have mentioned, it seems like it's a poor choice for your bike with making some changes (it's the same for my Kawasaki- others have found a power decrease when swapping the filter without adding fuel).

 

Ye unfortunately it seems like i got decrease in power. the z800 "punch" doesnt exist anymore. Feeling like driving a er6n again(love that bike tho)

 

will remove the filters and install the stock one again

 

Now i've noticed that the bike has having more difficulties reaching its top speed (goes to 202km/h and doesnt want to go up anymore)

 

 

 

Just curious but what speeds did you attain before the filter change?

 

not long after the first oil change i managed to reach 234 km/h (ofc at night on a straight highway with sufficent lightning and no animals or side roads)

 

I believe a lighter rider could go 250km/h if he would get in an aerodynamical shape + fit windshield on it

oh and do i have to disconnect the battery for few mins after changing the air filter so the ecu can adjust itself to the stock one again?

Personally while I agree any change in intake or exhaust flow benefits by an ECU update

that can "Take Advantage" of that change...( I have done so myself after changing intake & exhaust to further gains )

 

But...I tend to wonder if you do not have some other gremlin lurking

I would be very surprised that amount of increased air intake would have such a dramatic effect on your bike.

Who installed new air filter? Is it directional? Some are designed to flow one way

Also was it over oiled?

Because @ 32kph loss it almost sounds more like restriction than a small increase in air/intake

 

But your idea to replace the stock one & see is a good/logical process of elimination for figuring it out.

 

But I really do not think you would get that big of a difference on intake volume to be leaning out the bike

enough to show a 32kph loss. I could be wrong though so your experiment of reverting to stock is a good start.

 

As for the resetting the ecu I have read some folks say so but none with any real credentials

The ecu is variable only in the  low rpm closed loop section afaik

The main section is mapped & does not change unless map is changed via re-flash or EFI controller like Dynojet etc.

inserting new map & closing off the loop sensor

The only real way to see what's happening with modified airflows is to set it up on a dyno. Otherwise you (or your mechanic) are just guessing.

 

My old GSXR 750 had a free breathing pipe and filter fitted, which on their own gave a 1 bhp increase at the top end but a extended hole in the mid-range. I say extended hole because the original mapping on the stock pipe and filter had a huge hole in the mid-range anyway, effects of the strict emissions requirements.

 

After trying various ECU map changes using the Yoshimura remote programmer and testing on the dyno, we got all the mid-range hole filled in and about 4.5 bhp on the top end.

 

So, although I agree that it is strange that the top end speed is so highly affected by the changes, it could just be that the whole mapping is unsuitable with the pipe and filter and it's just that you, without a dyno, notice the effect at the top end as the most tangible effect.

 

What you do to adapt the mapping is up to you, but I would strongly recommend the Yoshi remap as it's reversible, doesn't require any extra electronics on the bike and is therefore invisible. It does mean that you can't mes around with it yourself at home or at the track though unlike a Power Commander or similar.

also is the scorpion a real one specifically designed for your bike? or a Thai fake or for another bike?

air filter and pipe need an aftermarket ecu to compensate extra air with fuel.

your bike needs and aftermarket ecu plus proper dyno tuning.

 

Yeah well when you mess about with things the oem ECU may not want to keep up with you.

thats what you did with your vigo then had to sell it,ha.

still alive then ? how is the old city.

 

 

 

A lot of guys here spend money changing things I understand it but me being a lot older and still alive   like my Kawasaki 650 bike as oem standard its well good enough, the gains aren't worth the hassle IMO. 

 

Vigo had a chip which I took off and sold before selling the Vigo.

 

Old City still OK more restaurants than people and some for sale.  

 

 

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)

 

besides the slip on and the air filter i have no other technical changes on the bike

 

and the slip on is specially made for the z800 by scorpion

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)

 

besides the slip on and the air filter i have no other technical changes on the bike

 

and the slip on is specially made for the z800 by scorpion

 

The enthusiasm I understand but what you fitted is different from oem so are you really reading what other guys are trying to tell you.

 

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)

 

besides the slip on and the air filter i have no other technical changes on the bike

 

and the slip on is specially made for the z800 by scorpion

 

The enthusiasm I understand but what you fitted is different from oem so are you really reading what other guys are trying to tell you.

 

 

yes i know what you mean.

 

forgot to tell you guys that i've ordered a new stock filter and i should be able to get it tomorrow. will let u know if there is any diff after a top speed run

Just a thought… you did oil the k&n didn't you?
If so, with what oil?

Sent from a telephone, which make and model is no concern of yours….

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)

 

besides the slip on and the air filter i have no other technical changes on the bike

 

and the slip on is specially made for the z800 by scorpion

 

O2 sensor work is done properly right?

I believe a dynojet will make your bike full power and more smooth.

 

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)

 

besides the slip on and the air filter i have no other technical changes on the bike

 

and the slip on is specially made for the z800 by scorpion

 

O2 sensor work is done properly right?

I believe a dynojet will make your bike full power and more smooth.

 

 

Im not sure but i've changed back to the stock filters and its running great now!

 

made a top speed run and reached 242 km/h (prolly cuz of the power increase of the scorpion slip on)

 

Everything is more crisp now. i knew it was weird before... just had an unsure.

 

Also i went to the exhaust shop since the owner didnt threw away my stock filters. the owner was very kind and did let me test ride his CB650f and man was it smooth. not as punchy and torquey like the z800 but very smooth and refined and i wish my z800 had the seating comfort like hondas do.

 

thanks for the help guys, appreciate that

dyno + fuel tuning is not an option to me since i'd have to drive from my city to bangkok (800km)
 
besides the slip on and the air filter i have no other technical changes on the bike
 
and the slip on is specially made for the z800 by scorpion

 
O2 sensor work is done properly right?
I believe a dynojet will make your bike full power and more smooth.

 
Im not sure but i've changed back to the stock filters and its running great now!
 
made a top speed run and reached 242 km/h (prolly cuz of the power increase of the scorpion slip on)
 
Everything is more crisp now. i knew it was weird before... just had an unsure.
 
Also i went to the exhaust shop since the owner didnt threw away my stock filters. the owner was very kind and did let me test ride his CB650f and man was it smooth. not as punchy and torquey like the z800 but very smooth and refined and i wish my z800 had the seating comfort like hondas do.
 
thanks for the help guys, appreciate that

There is nothing to do to the O2 sensor with just a slip-on

About the filter
Sounds like either the filter was in backwards or had too much oil.

A simple test is remove the filter & take a short run with no filter
If the theory is that the K&N flowed too much for the ECU you will see an
even lower top speed.

I would be very surprised though

It just may be to lean with the k&n. Without knowing the difference in airflow hard to say what's going on.

It just may be to lean with the k&n. Without knowing the difference in airflow hard to say what's going on.

 

Yes Yankee but sounds odd eh?

I mean given the flow difference between a K&N & stock is not much really

 

Also he has reduced exhaust restriction by adding the slip-on so if anything I would have guessed

opposite.

 

Odd deal really & makes me wonder about the install itself especially how much oil was soaked on the K&N

& I think K&N's are directional? Not sure as the DNA brand I have is not

 

Good he got his top end back but I would be curious still :)

 

It just may be to lean with the k&n. Without knowing the difference in airflow hard to say what's going on.

 

Yes Yankee but sounds odd eh?

I mean given the flow difference between a K&N & stock is not much really

 

Also he has reduced exhaust restriction by adding the slip-on so if anything I would have guessed

opposite.

 

Odd deal really & makes me wonder about the install itself especially how much oil was soaked on the K&N

& I think K&N's are directional? Not sure as the DNA brand I have is not

 

Good he got his top end back but I would be curious still

 

 

it has only a specific amount of oil coming with the box so i dont thinks so it is excessive oiling.

after a year or 10,000 km, you use a service kit to clean and oil the filter again.

maybe they did something wrong while installing it. strange case, i agree!