VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

So they dont get muddled and lost in the directory, please post your tuning questions here.

Moderator: Moderators

Post Reply
User avatar
Marcie
Posts: 55
Joined: Tue Jan 27, 2009 9:33 pm
My Bike: ZXRS400, CBR600
Location: DURHAM

VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by Marcie »

Hi all, tonight i was watching something about the new R1 and ive been toying with ideas for variable inlet trumpets.
Now i havent seen how yamaha have worked theirs, but i bet its a damn sight more technical than mine.!!!!!

Anyway ive drawn up a crude looking initial idea, and want to get your thoughts, ideas, advice and just generally your opinion!
I mean ive heard of some people putting longer inlet trumpets on the inside two cylinders so we all know that longer trumpets can help the top end, shorter ones for more grunt.
Obviously you would have to get a length that is short enough for grunt but can give good top end too.
So how about keeping the original trumpets, using a wider outer cylinder (so you dont loose volume) fix them to the carbs, once youve fabricated the plastic holder and the rest you can double the length of the trumpets, if the wires are run to the throttle housing slacken them off if theyre coming in too soon tighten them if too late.

Anyway im going to fabricate the bracket etc. Just for fun!!!!

MARCIE! :excited
You do not have the required permissions to view the files attached to this post.
Some body once told me... Theres only two things in life you'll ever need, Gaffa tape and WD40.
If it moves and it should'nt use Gaffa tape, if it doesnt move and it should use WD40!
User avatar
RedexRobB
Site Admin
Site Admin
Posts: 7212
Joined: Fri Aug 30, 2002 7:37 pm
My Bike: ZXR400L3
Location: Ipswich, Suffolk

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by RedexRobB »

I have no idea, but good luck and keep us updated! :D
User avatar
Marcie
Posts: 55
Joined: Tue Jan 27, 2009 9:33 pm
My Bike: ZXRS400, CBR600
Location: DURHAM

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by Marcie »

One post... on something that with all our idea's knowledge could be a quick mod maybe giving 5+ horsepower :D
Some body once told me... Theres only two things in life you'll ever need, Gaffa tape and WD40.
If it moves and it should'nt use Gaffa tape, if it doesnt move and it should use WD40!
lewisdale
CBT slow
CBT slow
Posts: 734
Joined: Mon Oct 06, 2008 5:41 pm
My Bike: zxr400 H2
Location: essex

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by lewisdale »

if it works well mate u can make me some up providing there not made of gaffer tape n cable ties :pmsl
User avatar
Marcie
Posts: 55
Joined: Tue Jan 27, 2009 9:33 pm
My Bike: ZXRS400, CBR600
Location: DURHAM

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by Marcie »

Cheeky ;)
no promises!
Some body once told me... Theres only two things in life you'll ever need, Gaffa tape and WD40.
If it moves and it should'nt use Gaffa tape, if it doesnt move and it should use WD40!
User avatar
hciR
zxr400 oc member
zxr400 oc member
Posts: 249
Joined: Wed Aug 23, 2006 9:06 pm
My Bike: zxr 400
Location: Surrey

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by hciR »

I managed to unearth a bit of info on this. See: http://auto.howstuffworks.com/question517.htm
Near the end it mentioned having two seperate intakes with a valve to switch between them. Only problems I can see are the space it would take up, and how well it works with carbed engine (i'd imagine the article is about injection?).
User avatar
Marcie
Posts: 55
Joined: Tue Jan 27, 2009 9:33 pm
My Bike: ZXRS400, CBR600
Location: DURHAM

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by Marcie »

Hi HicR,
Read that article, Interesting what it says about the speed of the pressure waves and what not. At the end its talking about diameter of the intake, im talking about length.
Im going to research how velocity stacks work (properly) and report back here.
Thanks anyway
Some body once told me... Theres only two things in life you'll ever need, Gaffa tape and WD40.
If it moves and it should'nt use Gaffa tape, if it doesnt move and it should use WD40!
will#224
L-plate hell
L-plate hell
Posts: 330
Joined: Sat Aug 09, 2008 11:49 pm
My Bike: L1 racer

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by will#224 »

I too have been researching this lately, there is already an ignition module available to allow servo control. You could even go fly by wire if you wanted as per the newer R6. The inlet can sometimes benefit from been a fixed length with a part removed lower down to create turbulant air which could be a simpler option.

Are you looking at this for a race bike? I am and wonder how a club would view this with the recent stop on fuel injection. FCR carbs or standard?

Will
User avatar
Marcie
Posts: 55
Joined: Tue Jan 27, 2009 9:33 pm
My Bike: ZXRS400, CBR600
Location: DURHAM

Re: VARIABLE INLET TRACTS / TRUMPETS... IDEAS!!!!!!!!!!!!!!!!!!!

Post by Marcie »

Im not looking at this for racing, but its useless on the standard zxr, the air box has no way enough room above the carbs. A possability with a ram air box perhaps??
I scrapped the idea for my bike, and moved on to my mates gsf600, nice big airbox! something for the future.

As for turbulance, sounds like a good idea, If you did it right you would get a variable inlet effect, by that i mean at low revs the air would enter through the higher opening and on full wack, both or the bottom/side opening would draw the air in.

Who wants to hack their stack's up for the purposes of experiment??!! That seems like the new idea, scrap mine unless youve got room and understand pressure waves, which i didnt when drawing up my sketch on paint! :D
Longer means the RPM lowers which increses torque. Shorten the stacks and you get Higer rpm and top end.

Those of you famillia with massimo tamburini will know he created TTS, and that is used on the MV Augusta's, and obviously we are all aware of yamaha's version.

Marcie
Some body once told me... Theres only two things in life you'll ever need, Gaffa tape and WD40.
If it moves and it should'nt use Gaffa tape, if it doesnt move and it should use WD40!
Post Reply