To flatslide or not to Flatslide?

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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Racer93
Posts: 4
Joined: Tue Apr 23, 2013 5:15 pm
My Bike: Aprilia SXV

To flatslide or not to Flatslide?

Post by Racer93 »

Hi guys,

I have built a racer from a part finished project bike and am considering fitting flat-slides.

The guy I bought the part finished racer off said not to fit them as the ZXR is easier to race with CV's.

I have always raced 2 strokes so would appreciate some advice.

First shake down track day had the mother of all flat spots at 8K.
Would not pull through without kicking it down a gear and forcing it over 8K then it rev'd it's head off.

My thinking is carbs are probably worn or blocked internally. (I cleaned them with petrol and an airline but they were full of crud.)

Any advice would be appreciated as I hope to be out in 4 weeks.

cheers

Martin
ChowderV4
Posts: 98
Joined: Mon Dec 24, 2012 7:57 pm
My Bike: Zxr400L racer

Re: To flatslide or not to Flatslide?

Post by ChowderV4 »

from my experience, having used both this season the cv's are far far easier to set up and get good power from.

but, with flatslides properly set up, (which is known to be hard) they are the best for getting the most power out of your machine , especially with ram air set up.

I cant afford the dyno time to set up the flatslides so i have returned back to the cv carbs
Lou0155
Posts: 6
Joined: Wed May 13, 2015 8:09 am
My Bike: ZXR400

Re: To flatslide or not to Flatslide?

Post by Lou0155 »

Hi , Chower v4 you made mention you have gone back to the CV carbs , could you share you carb set eg -pilot jets main jet and needle ?
We don,t run a ram air setup just a Carbon fibre tray that that's air from the front
Any info would be great
Lou0155
Posts: 6
Joined: Wed May 13, 2015 8:09 am
My Bike: ZXR400

Re: To flatslide or not to Flatslide?

Post by Lou0155 »

Hi , Chowder v4 you made mention you have gone back to the CV carbs , could you share you carb set eg -pilot jets main jet and needle ?
We don,t run a ram air setup just a Carbon fibre tray that that's air from the front
Any info would be great
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Mori Man
Blingmeister
Blingmeister
Posts: 1976
Joined: Thu May 10, 2007 3:30 pm
My Bike: ZXR400J2
Location: JAPAN

Re: To flatslide or not to Flatslide?

Post by Mori Man »

Stock FCrs from a SP bike will not work well on a race bike - you need to internally " kit " them out - then your bike will fly :smt003

I only ever use flatties on my road bikes and have no issues with them once set up.

I changed bacl to CVK's for a week - that wont happen again , thought I had killed the engine :pmsl

Having the proper needles in the FCrs is the key though
Nothing worse than having an H and not being able to scratch it !
Living life on the edge, SuPposedly
Brian28
Posts: 9
Joined: Mon Jul 16, 2012 9:04 am
My Bike: Kwacker

Re: To flatslide or not to Flatslide?

Post by Brian28 »

Aside from power/set up issues, worth checking your intended race series. Flatsides will make your bike illegal in most F400 championships so you may end up with a bike that you can't race within the rules.
AFM327
L-plate hell
L-plate hell
Posts: 307
Joined: Sat Aug 02, 2008 4:29 pm

Re: To flatslide or not to Flatslide?

Post by AFM327 »

MoriMan has it right, set up well flatslides are much better. My bike will pull from down low even if I'm ham fisted and giving it full throttle. It spent a lot of time on the dyno getting it right though, and it has custom needles. :)
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mark400
Posts: 208
Joined: Fri Feb 06, 2009 11:48 pm
My Bike: Building an original SP

Re: To flatslide or not to Flatslide?

Post by mark400 »

Martin : If you don't use flatslides and want to sell them - I'm after some for an SP rebuild I am doing at the moment !
NG Road Racing Champion 2012 400SS
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mark400
Posts: 208
Joined: Fri Feb 06, 2009 11:48 pm
My Bike: Building an original SP

Re: To flatslide or not to Flatslide?

Post by mark400 »

Mori and AFM - You mention the right set up and proper custom needles - can you give any more info ? I think I have bought a set* and want to get them running right !

*not arrived yet
NG Road Racing Champion 2012 400SS
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mark400
Posts: 208
Joined: Fri Feb 06, 2009 11:48 pm
My Bike: Building an original SP

Re: To flatslide or not to Flatslide?

Post by mark400 »

FCR33's now arrrived :excited

Anyone have the TPS or choke rail off the SP Flatslides ?

Looking to buy these parts for my SP Build

Alternatively - Is this TPS used on any other models ?
NG Road Racing Champion 2012 400SS
rccaulfield
Posts: 34
Joined: Tue Sep 25, 2012 12:26 am
My Bike: zxr 400l sp
Location: Ireland

Re: To flatslide or not to Flatslide?

Post by rccaulfield »

Iv a tps on my flatslides but theyr not plugged into the loom so bike was set up on dyno without them?
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