ramair box

There seems to be more and more members appearing that are racing the ZXR400 so i've created a special section just for you to show off results, discuss meets etc etc.

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mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

ramair box

Post by mitchpaul »

just fitted a ramairbox to my zxr400l ,now down long straigths on the race track it only revs to 12k it use to go to14500 i have flat slides with 114 jets have tried 122 and 130 and no better ,it has standard h cams and mild porting and kit type exhaust
chief
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Joined: Sat Nov 10, 2007 7:08 pm

Re: ramair box

Post by chief »

try takeing the fuel filter out before the pump as it sounds like fuel starvation to me ! also if flatties have no other mods i run 145 mains ! there is also some small filters behind the needle valves that can block ? you have to bear in mind that flatslides use considerably more fuel than cv ?
mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

Re: ramair box

Post by mitchpaul »

Filters are all good when i take box lid of it revs out fine i have 30mm stacks on carbs
zimm
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Re: ramair box

Post by zimm »

which ram-air box have you fitted ? kit ? kit copy ? rmkd ? etc ..

i'd try asking whoever made it what their recommended starting point for setup is.

having said that.. if it revs out under load with the lid off, then logic say's its running rich with it fitted .. so try smaller jets.. ?

I've never used flatties, but i had an H1 on CV's with beet exhaust that plateau'd @12k.. was rich at the topend.. smaller jets, modded airbox (stock) and tweaked ignition (ignitech) moved peak power up to 14,700, and it would happily run into the 15,250 limiter

has anything else been changed at the same time ? cams/ignition etc ?
mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

Re: ramair box

Post by mitchpaul »

its a rmkd copy and nothings been changed i could go to 110 jets, but they should be far to small, ? How would i tell if its to lean
cargo
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Re: ramair box

Post by cargo »

Dyno ? ? ? ?
mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

Re: ramair box

Post by mitchpaul »

What mains do you guys use with flats and ram air box
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mick41zxr
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Joined: Wed Jan 14, 2009 4:07 am
My Bike: ZXR400sp

Re: ramair box

Post by mick41zxr »

Are they original SP with a round main or aftermarket kehins with a hex main.
Around 140 for round main or 120 for hex.
This is also dependent on main air jet size & float level
Regards,
MB
mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

Re: ramair box

Post by mitchpaul »

The flatslides had the 9mm long hex ones, i have put in round cv type because thets what i had would this make a difference
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Mori Man
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Re: ramair box

Post by Mori Man »

mitchpaul wrote:The flatslides had the 9mm long hex ones, i have put in round cv type because thets what i had would this make a difference
" Does a bear toad in the woods ? "

:smt018
Nothing worse than having an H and not being able to scratch it !
Living life on the edge, SuPposedly
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mick41zxr
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Re: ramair box

Post by mick41zxr »

I think Mori has the answer for you,
There may be a chance that you main jet is clearing the fuel level???
Regards,
MB
zimm
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Re: ramair box

Post by zimm »

Just ring Roger, his number will come up on a google search easily enough if you havent already got it ..

I'm sure having made the airbox he'll be able to give you an initial setup
mitchpaul
Posts: 10
Joined: Tue Jun 08, 2010 9:28 am
My Bike: zxr400l 1993

Re: ramair box

Post by mitchpaul »

my main air jets are 200s ? is this ok
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mick41zxr
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Re: ramair box

Post by mick41zxr »

Yes, What is the needle code? try it with the long hex jets, my jetting runs from 118 to 122 mains depending on atm pressure/track.
I run 118 at Wakefield, 120 at Eastern Creek & 122's at Phillip Island. Check your float levels, do not deviate from the manual.
Regards,
MB
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mick41zxr
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Re: ramair box

Post by mick41zxr »

You can really feel/hear when you have them on song ;)
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