Carburetor jets and box - Ex-500.com - The home of the Kawasaki EX500 / Ninja 500R
 2Likes
  • 1 Post By 11Motos
  • 1 Post By K-woppa
 
LinkBack Thread Tools
post #1 of 17 (permalink) Old 5-10-2019, 7:28 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
Carburetor jets and box

Hi everyone. I am new here.
I am going to re-jet the carbs and improve the lift for a faster response.
Any suggestions on jets and needle kits?

I also want to cut the box at the top in the back and cancel the vacuum cleaner (so called snorkel) that is in a horrible location.
Specially because I am going to do adventure riding that means gravel running and forest areas.

Any thoughts, suggestions?

Thanks!!
Attached Images
File Type: jpg KawaNinjaIntakeBox1.JPG (59.4 KB, 19 views)
11Motos is offline  
Sponsored Links
Advertisement
 
post #2 of 17 (permalink) Old 5-11-2019, 1:44 PM
Member
 
johna6968's Avatar
 
Join Date: Jan 2019
Location: Cheshire UK
Posts: 68
 
Never really saw the ninja / gpz as a forest gravel adventure bike, but hey whatever works for you. Go careful with that airbox chopping n changing, those dudes at kawasaki put a lot of thought into it. There is a FOG mod for the airbox on here if you have a search.
johna6968 is offline  
post #3 of 17 (permalink) Old 5-11-2019, 5:02 PM
Senior Member
 
Join Date: Nov 2017
Location: England UK
Posts: 296
 
sorry to be blunt but you are wasting your time. all you will do playing around with stock kit is give yourself a Migraine it's designed like that for a reason. there is no reason to change it. it's hidden behind the cover so what gives. air flow is carefully calculated on this bike change it at your peril. want to go off road get a dirt bike. it's not what the EX is for.
yorkie is offline  
 
post #4 of 17 (permalink) Old 5-11-2019, 6:13 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
I already cut the box and created a membrane to control back pressure. Next I am going to introduce a barometer to compare to the stock.
Since it is gated it is completely reversible so lets see what happens.
I don't need a dirt bike. I have two already. this is different.
11Motos is offline  
post #5 of 17 (permalink) Old 5-11-2019, 10:30 PM
Super Moderator
 
K-woppa's Avatar
 
Join Date: Mar 2012
Location: SE MA
Posts: 3,339
 
I'm curious about this myself, because I don't exactly understand what it is you're doing. It sounds like the premise is, the intake will suck in more dirt because of the orientation of the trumpet. If we were talking about a ram air setup I would wholeheartedly agree, but it seems to me that's actually a pretty well protected location. I also don't understand what the membrane is accomplishing and what you mean by "back pressure".

No matter, I always like it when people are willing to try honest experimentation. If you're going to measure the airbox (negative) pressure for comparison I would do so on the engine side of the filter. It sounds like you already understand the importance of this pressure to fuel metering and slide calibration. I'm looking forward to seeing what you come up with.
K-woppa is offline  
post #6 of 17 (permalink) Old 5-11-2019, 11:07 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
By back pressure I meant negative pressure sorry. Since the port is gated not just a random hole, I can adjust like in certain airboxes in the old times.
There is another alternative that is two outside snorkels pointing where the air might be cleaner and cooler. I also want them higher off the ground.
The idea is to improve certain areas for long trips adventure ridding while keeping some of the other nice attributes and wonderful engine, obviously.
If the KLR 500 twin had made it to the USA (Same engine) I would have one of those but since they didn't the EX will have to do.
There is no mid size twin in the market without being a larger engine or heavier bike.

Here is an idea from this GS500...

Devilsfan likes this.
11Motos is offline  
post #7 of 17 (permalink) Old 5-12-2019, 5:53 AM
Senior Member
 
Join Date: Nov 2017
Location: England UK
Posts: 296
 
yeah as someone once said it's your bike. but do some more research on the EX. it not just a matter of negative pressure but how that negative pressure gets to the carb intakes and the route it takes. also there is the engine tune to consider. the EX is a screamer 6k and above the KLE 500 [freely available here in the UK] isn't as the state of tune is reduced in fact it's a completely different animal. the snorkel fitted to the airbox on this bike is on top pointing forwards but the air intake duct is at the btm of the air box. me thinks you are in for a interesting time ahead hope it works out just keep a good supply of tablets handy your going to need them.
yorkie is offline  
post #8 of 17 (permalink) Old 5-12-2019, 8:34 AM
Super Moderator
 
K-woppa's Avatar
 
Join Date: Mar 2012
Location: SE MA
Posts: 3,339
 
We have seen a number of people adapt the ex500 for dual sport use. One guy did an exceptional job, putting KDX forks on it and such. As I remember he was happy with it.

As far as the powerband goes, I think the engine is tractable enough, though really tight trail work might be a challenge. But, you already have bikes for that.
K-woppa is offline  
post #9 of 17 (permalink) Old 5-12-2019, 12:44 PM
Senior Member
 
Davenay67's Avatar
 
Join Date: Dec 2018
Location: Lisle, IL
Posts: 104
 
I applaud your obvious knowledge, skills, tenacity and can-do-it approach. I hope you are successful and get want you want.

However....Kawasaki already did all the work for you. Sell the EX and buy the proper job....

Davenay67 is online now  
post #10 of 17 (permalink) Old 5-12-2019, 3:05 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
Yes I have been talking to him about the KDX. It is a great alternative for the front end but I want something more beefed up since I am 6.2 and 242lbs.
I have decided to machine the tripple tree out of T6 and that way I can keep the original offset dimensions and install the massive 49mm forks from the DRZ.
I will also machine a bracket so I can use a 300-320mm disk for additional stopping power. I can do that later not needed for day one.
11Motos is offline  
post #11 of 17 (permalink) Old 5-12-2019, 3:16 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
Quote:
Originally Posted by Davenay67 View Post
I applaud your obvious knowledge, skills, tenacity and can-do-it approach. I hope you are successful and get want you want.

However....Kawasaki already did all the work for you. Sell the EX and buy the proper job....


That is a lovely bike in deed but it is a tradeoff in terms of road use and also not great off road due to the heavy weight and obsolete suspensions.
Everything can be improved in the KLR but I already have a 500 in need of some TLC and she is whispering in my ear she wants to see the world.
Who am I to deny such a privilege to this wonderful kawa 500 we love so much? lol
11Motos is offline  
post #12 of 17 (permalink) Old 5-12-2019, 3:28 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
My son and I have been studding the jetting and we think we will keep all the original jets and parts.
we will just give it a good cleaning and a few minor adjustments.
The only think that I might do is to open a 1/8 hole in the slider and taper the needle a tad since it is too lean off idle.
This should advance the response off idle and have a slight faster response. Thoughts?

Everything else I like but I feel the 1/2 bottom end is where I am going to run most of the time strolling back asphalt and dirt roads
that is where 80% of the ADV ridding happens. I will play with the exhaust too. I see some welding in my future.

Ninja 250 ADV version. I like it but I see several important things missing for me.

Attached Images
File Type: jpg nina250adv.JPG (132.2 KB, 38 views)

Last edited by 11Motos; 5-12-2019 at 3:31 PM.
11Motos is offline  
post #13 of 17 (permalink) Old 5-12-2019, 3:36 PM
Senior Member
 
Davenay67's Avatar
 
Join Date: Dec 2018
Location: Lisle, IL
Posts: 104
 
Quote:
Originally Posted by K-woppa View Post
We have seen a number of people adapt the ex500 for dual sport use. One guy did an exceptional job, putting KDX forks on it and such. As I remember he was happy with it.

As far as the powerband goes, I think the engine is tractable enough, though really tight trail work might be a challenge. But, you already have bikes for that.
I have a KDX200 sat in my garage. Long forks; bikes has a 37.5" seat height. You'd need some big rear shock to compensate, or else you'd look like one of those raked-out choppers from the 70's.

Plus, KDX front forks are old tech and basically crap. Anyone serious about their KDX ditches the forks and does a USD from swap from a KX.
Davenay67 is online now  
post #14 of 17 (permalink) Old 5-12-2019, 4:51 PM
Super Moderator
 
K-woppa's Avatar
 
Join Date: Mar 2012
Location: SE MA
Posts: 3,339
 
Quote:
Originally Posted by 11Motos View Post
My son and I have been studding the jetting and we think we will keep all the original jets and parts.
we will just give it a good cleaning and a few minor adjustments.
The only think that I might do is to open a 1/8 hole in the slider and taper the needle a tad since it is too lean off idle.
This should advance the response off idle and have a slight faster response. Thoughts?

Everything else I like but I feel the 1/2 bottom end is where I am going to run most of the time strolling back asphalt and dirt roads
that is where 80% of the ADV ridding happens. I will play with the exhaust too. I see some welding in my future.

Ninja 250 ADV version. I like it but I see several important things missing for me.

The ex500 came from the factory with an off-idle lean stumble due to the lean factory setting of the pilot screws for emissions certification purposes. Plus, the pilot circuit jets and passages are tiny and prone to clogging from stale gas. Today's gasoline tends to form gunk after a relatively short time of sitting. Properly cleaned and with pilot crews adjusted, throttle response on these bikes is really good. Since you've studied the jetting, you know that it's already a bit fat overall in stock form.

It sounds to me that you're trying not to alter the intake restriction while repositioning the intakes. If so, I'll think you'll be well served by just making sure the pilot circuit is clear and the screws are properly set. They're usually about 1 1/2 to 1 3/4 turns out from the factory. 2 1/2 turns is the recommended starting point for adjustment. I don't think you'd need to shim the slides.
11Motos likes this.
K-woppa is offline  
post #15 of 17 (permalink) Old 5-12-2019, 7:25 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
Wise words k-woppa. I might just to do a test after re-positioning the air intake because we should not alter more than one thing at the time. Otherwise we will not know for sure what make a difference if any. the main reason I like this engine for the role is because its docile nature and torque 20ft-lbs at 5.5k rpm or so. In the dirt is important to have torque to tractor around but
not so much fast that it might come w/o warning. There are plenty of competition machines but I like the idea of a bike that I can find myself on any corner of the planet and easily locate parts for it.

Last edited by 11Motos; 5-12-2019 at 8:36 PM.
11Motos is offline  
post #16 of 17 (permalink) Old 5-12-2019, 8:35 PM Thread Starter
Junior Member
 
11Motos's Avatar
 
Join Date: May 2019
Location: On the road
Posts: 26
 
Quote:
Originally Posted by Davenay67 View Post
I have a KDX200 sat in my garage. Long forks; bikes has a 37.5" seat height. You'd need some big rear shock to compensate, or else you'd look like one of those raked-out choppers from the 70's.

Plus, KDX front forks are old tech and basically crap. Anyone serious about their KDX ditches the forks and does a USD from swap from a KX.
Hi,
IMO they are not the worse since at least they are cartridge simple and reliable but I would agree they are on the light (also soft) side for this and would need the strongest springs we can find.
The only reason was because they share the same lower and upper bearings so it is a direct plug in but not a huge deal. They give decent clearance when turning but since the offset
dimension is different this automatically cancels this option for me. It might be ok for others.

In reality there is no 100% straight shot plug in and I wanted to avoid extra work like machining / lathe time but not the end of the world.
That is why I am going with the 39mm of the DRZ. Probably the same DRZ wheel or a 19" one. Have not decided yet.
Then I will have to machine a the triple trees from scratch to get the offset distance and clearance I want. the advantage is that I machine this from a billet
I can provision support for other things like auxiliary lights or even a hook for small pulley.

At the same time and as you well pointed out the KDX in original form would be way too high for this bike and it cannot be risen (or should be risen) that high anyway. so it will be have
to be done to preserve the proper ridding geometry and front suspension might need to be lowered and limited to match. I don't want to go too high. I will be conscious of extra clearance
but I also want to be able to ride over a wash or rocks like it is nothing and w/o bottoming out.

Many thanks for you input. I know the KDX is doable but will not be my choice. It is like the DR650 they are great donors at first glance but they will need re-valving and springs and
then they behave close to a high end cartridge fork but it is additional time and $s.
Same with the rear shock it needs re-valving and new piston. So considering all additional expenses I will go big yet budget conscious and make
sure the front end can take a hit although is not going to any competition.
11Motos is offline  
post #17 of 17 (permalink) Old 5-13-2019, 3:09 AM
Member
 
johna6968's Avatar
 
Join Date: Jan 2019
Location: Cheshire UK
Posts: 68
 
Iv owned the KLE500 and it is a good bike but agreed its a totally different motor in character than the gpz/ninja. Good luck with the modifications and Im genuinely interested to see the outcome.
johna6968 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ex-500.com - The home of the Kawasaki EX500 / Ninja 500R forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome