ADVrider

Go Back   ADVrider > Bikes > Thumpers
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 07-28-2011, 05:51 PM   #4051
Sateev
Gnarly Adventurer
 
Joined: Nov 2010
Location: Thailand
Oddometer: 118
Quote:
Originally Posted by Trailrider200 View Post
removing the airbox lid changed the helmholtz resonator effect of the airbox. to compensate u have to use a larger mj. same thing happens when POD filters are installed.
http://www.thunderproducts.com/AirboxesDynotech.htm
http://www.saltmine.org.uk/randy/airboxdesign.html
buy having too big an opening the carb has a harder time drawing fuel up the mj/needle well due to pressure differentials. using a bigger mj conpensates for this. So it got lean from less fuel not more air. This is what most don't understand. So in actuality nothing for performace actually was accomplished except your smaller wallet. now if the airbox opening is actually smaller then the carb bore, then the carb is air restricted and opening the airbox will help. I'm sure jesse knows this, but he can't sell product to people who know how a carb and its airbox works. muffler mod is worth it and would require a larger mainjet. He only goes up one size on the pilot jet. The mixture screw can be opened up to 4 1/2 turns before a next size PJ is required. notice the larger PJ that is used yet the idle mixture screw position is the same as OEM PJ.
my whole point is the stock airbox with the stock openings flow enough air for the carb. The metal screen inside of the foam airfilter is the restriction. A paper filter has lower restriction than a foam filter of the same size. A foam filter has to be much larger to flow the same as a paper filter. the height of a filter effects flow more then the dia. of the filter.
excellent write up on cv carbs
http://www.drpiston.com/Cvcarbs.html
First, a quote from the page you linked. The ability to read critically, rather than regurgitation, is the key principle:

"How can this effect be useful? Well, imagine that peak torque is OK, but the engineís a little weak at closing the clutch. No problem; just set the box resonance to give a little boost right at the rpm where itís needed. Or perhaps your exhaust pipes are a little sharp, leaving the engine an airless weakling right where a lot of people want to ride it? Fill in that hole with airbox power. Or maybe you just need to make a bigger number to fill a vacuum thatís formed between the admen and the dyno? Stack that box resonance right on top of peak torque."

The resonance you speak of occurs at a specific RPM band. Suzuki did not design the airbox with peak performance in mind, and if you consider the cam timing, and the ragged-edge lean condition that comes stock, it becomes clear that the bike is set up for low-end grunt, not top end power.

So, by defeating Helmholtz (which only had an effect at the bottom end), and increasing airflow across the RPM range, you have tuned the motorcycle for a different powerband.

The idea that the airbox inlets are sufficient, because the REAL restriction is at the filter, or mesh screen, is silly. Because air is a spring (from the simplified article) does NOT mean that the restrictions are discrete; they are, in fact, cumulative. Each restriction you remove will contribute to airflow. Now, we can debate WHICH restriction will have the most effect, and I might have to concede the mesh, although (this is important), without a flow bench, it is too complex a problem to be solved on paper.

Which brings us to Jesse and Kientech, and the literally dozens of people who have successfully either modified their airbox lid, or removed it completely, along with jet changes. While not as scientific as measuring it with a flowbench, there is plenty of evidence that this mod works. In my case, top speed and acceleration have improved. Don't bother telling me it's just my imagination or the new sound. It works, period.

And Jesse could sell just as many kits by just rejetting/changing the needle to eliminate the factory lean condition, without the airbox suggestion. I find your implication that he is just doing it to lighten my wallet offensive. If I were you, I would hastily retract it.

Maybe you need to Google some more, and come up with a hypothesis explaining the increased performance that so many have obtained.

Then, get back to us.
Sateev is offline   Reply With Quote
Old 07-28-2011, 08:30 PM   #4052
bross
Where we riding to?
 
bross's Avatar
 
Joined: Nov 2005
Location: Osoyoos, BC
Oddometer: 4,469
Quote:
Originally Posted by Sateev View Post
First, a quote from the page you linked. The ability to read critically, rather than regurgitation, is the key principle:

"How can this effect be useful? Well, imagine that peak torque is OK, but the engineís a little weak at closing the clutch. No problem; just set the box resonance to give a little boost right at the rpm where itís needed. Or perhaps your exhaust pipes are a little sharp, leaving the engine an airless weakling right where a lot of people want to ride it? Fill in that hole with airbox power. Or maybe you just need to make a bigger number to fill a vacuum thatís formed between the admen and the dyno? Stack that box resonance right on top of peak torque."

The resonance you speak of occurs at a specific RPM band. Suzuki did not design the airbox with peak performance in mind, and if you consider the cam timing, and the ragged-edge lean condition that comes stock, it becomes clear that the bike is set up for low-end grunt, not top end power.

So, by defeating Helmholtz (which only had an effect at the bottom end), and increasing airflow across the RPM range, you have tuned the motorcycle for a different powerband.

The idea that the airbox inlets are sufficient, because the REAL restriction is at the filter, or mesh screen, is silly. Because air is a spring (from the simplified article) does NOT mean that the restrictions are discrete; they are, in fact, cumulative. Each restriction you remove will contribute to airflow. Now, we can debate WHICH restriction will have the most effect, and I might have to concede the mesh, although (this is important), without a flow bench, it is too complex a problem to be solved on paper.

Which brings us to Jesse and Kientech, and the literally dozens of people who have successfully either modified their airbox lid, or removed it completely, along with jet changes. While not as scientific as measuring it with a flowbench, there is plenty of evidence that this mod works. In my case, top speed and acceleration have improved. Don't bother telling me it's just my imagination or the new sound. It works, period.

And Jesse could sell just as many kits by just rejetting/changing the needle to eliminate the factory lean condition, without the airbox suggestion. I find your implication that he is just doing it to lighten my wallet offensive. If I were you, I would hastily retract it.

Maybe you need to Google some more, and come up with a hypothesis explaining the increased performance that so many have obtained.

Then, get back to us.
Just came in from installing Jesse's jet kit on Jodie's DR200. Man these 200's are easy to work on. Very simple and straight forward install, especially considering I've never done one before. Put it all back together, started and ran like a champ. I could even wheelie, OK a small one, with my large ass on it. Jodie hasn't ridden it yet for the final verdict but will report back as soon as she has a chance to take it for a ride.

I can't even begin to figure out how all this works so I really appreciate those who have, so I can simply install something and have it work. Thanks Jesse, Janet and those who have shared their knowledge on this thread.
bross is offline   Reply With Quote
Old 07-28-2011, 09:16 PM   #4053
Sateev
Gnarly Adventurer
 
Joined: Nov 2010
Location: Thailand
Oddometer: 118
Hey Bross,

Pretty cool, huh?

I hesitated for a long time because my pilot jet was broken, and I didn't want to break it any further, since I am far from a parts supplier. When I finally tackled it, and it ran so well, I was kicking myself for not doing it sooner!

And I echo your thanks to people who come here, experiment, learn, and then share it with the rest of us. Guys like Jesse, and the guys at ProCycle just seem to like tuning and making things work. I doubt they'd be in it if it was only for the money...

This forum is the best use of my time, when it comes to making my bike the way *I* want it. Thanks to all.
Sateev is offline   Reply With Quote
Old 07-28-2011, 09:48 PM   #4054
Klay
dreaming adventurer
 
Klay's Avatar
 
Joined: Nov 2005
Location: right here on my thermarest
Oddometer: 99,159
It is indeed easy to work on. When I put the Kientech jets in mine, its cold running manners were greatly improved, plus there seems to be slight improvement in power. It's a well-sorted solution.
Klay is offline   Reply With Quote
Old 07-29-2011, 11:12 AM   #4055
Trailrider200
Gnarly Adventurer
 
Trailrider200's Avatar
 
Joined: Nov 2010
Location: Exit 10A, RT 42
Oddometer: 284
[QUOTE its cold running manners were greatly improved, plus there seems to be slight improvement in power. [/QUOTE]

opening up the idle mixture screw 3 to 3 1/2 turns does the same thing with the stock pilot jet.
stock PJ is good up to 4 1/2 turns open.
__________________
1981 CB900C, 1998 GL1500C Valkyrie
2007 DR200

"Our Constitution was made only for a Moral and Religious people. It is wholly inadequate to the goverment of any other."
John Adams 10/11/1798

"If we ever forget that we're one nation under God, then we will be a nation gone under" Ronald Reagan
Trailrider200 is offline   Reply With Quote
Old 07-30-2011, 01:48 PM   #4056
acif
Adventurer
 
Joined: Jan 2010
Oddometer: 47
does anyone knows if the early dr350 rotor (4 holes) can fit into the dr200 hub.

from the specs, the two rotors share the iner diamenter (120mm), the number of holes (4), the distance between mounting holes (142 mm), and the diameter of those holes (10.5mm).

the only difference is the outer diamter: 230mm in the DR200 and 250mm in the DR350.
acif is offline   Reply With Quote
Old 07-30-2011, 05:50 PM   #4057
ben2go
Moto Flunky
 
ben2go's Avatar
 
Joined: Jun 2011
Location: Upstate SC USA
Oddometer: 3,159
Quote:
Originally Posted by acif View Post
does anyone knows if the early dr350 rotor (4 holes) can fit into the dr200 hub.

from the specs, the two rotors share the iner diamenter (120mm), the number of holes (4), the distance between mounting holes (142 mm), and the diameter of those holes (10.5mm).

the only difference is the outer diamter: 230mm in the DR200 and 250mm in the DR350.

With that much outer diameter difference,it won't work without offsetting the caliper somehow.
ben2go is offline   Reply With Quote
Old 07-30-2011, 07:55 PM   #4058
acif
Adventurer
 
Joined: Jan 2010
Oddometer: 47
Quote:
Originally Posted by ben2go View Post
With that much outer diameter difference,it won't work without offsetting the caliper somehow.

yes, it might be imperative to make a relocating bracket, but is doesnt matter because the DR350 rotor will bring a 10% of gain in brake torque.
acif is offline   Reply With Quote
Old 07-30-2011, 09:59 PM   #4059
Klay
dreaming adventurer
 
Klay's Avatar
 
Joined: Nov 2005
Location: right here on my thermarest
Oddometer: 99,159
Klay is offline   Reply With Quote
Old 07-31-2011, 11:49 AM   #4060
ben2go
Moto Flunky
 
ben2go's Avatar
 
Joined: Jun 2011
Location: Upstate SC USA
Oddometer: 3,159
Sweet ride Klay.
ben2go is offline   Reply With Quote
Old 08-01-2011, 08:56 AM   #4061
Birdmove
Beastly Adventurer
 
Birdmove's Avatar
 
Joined: Oct 2004
Location: Keaau, Hawaii
Oddometer: 1,602
Quote:
Originally Posted by Klay View Post
Nope, I'm going to change it at much shorter intervals.


I don't have a DR200, but I did ride a Yamaha XT225 for a few years. It had a one quart oil capacity. I always changed at 1000 miles as the small engine worked pretty hard. At break in I did the first change at 50 miles and found a lot of crap on the filter.Changed again at 300 and found some more. After that no more crap. The bike ran well used no oil between changes. Now on my 2006 Sportster XL883-an engine that dosen't constantly rev it's little heart out, I have backed off and change oil and filter at 2500 miles.It holds three quarts. On various scooters we have owned I always changed at 1000 miles as they always rev high.

jon
__________________
Jon in Keaau, Hi. USA
2008 SYM HD200 (wife's ride)
2009 Kymco People 150 and coming soon, another dual sport mc

Birdmove screwed with this post 08-06-2011 at 08:57 AM
Birdmove is offline   Reply With Quote
Old 08-01-2011, 04:49 PM   #4062
amtz.zero
Adventurer
 
amtz.zero's Avatar
 
Joined: Mar 2011
Location: Moreno Valley, CA
Oddometer: 64
Has anyone here checked if a dr350 rear fender will fit on a dr200? I want to put a Maier mx fender on a dr200 but it's only made for the 350. Should it fit? Has anyone put this rear fender on their 200?
amtz.zero is offline   Reply With Quote
Old 08-02-2011, 05:12 PM   #4063
alvycolt45
Adventurer
 
alvycolt45's Avatar
 
Joined: May 2010
Location: I-80 Nevada-Utah border
Oddometer: 37
Just though I'd share a pic from yesterday when my DR200 conquered some steep switchbacks while carrying my fat ass.

alvycolt45 is offline   Reply With Quote
Old 08-02-2011, 05:37 PM   #4064
bross
Where we riding to?
 
bross's Avatar
 
Joined: Nov 2005
Location: Osoyoos, BC
Oddometer: 4,469
Great pic!
bross is offline   Reply With Quote
Old 08-03-2011, 01:34 PM   #4065
canuck76
Gnarly Adventurer
 
canuck76's Avatar
 
Joined: Oct 2009
Location: Creedmoor, North Carolina
Oddometer: 159
Quote:
Originally Posted by bross View Post
Sorry just haven't got the miles on our DRs yet, I'm at 10,000kms on my 650 and Jodie just turned over 6,000kms on her 200, both 2007s. We're riding the DRs more than our street bikes now so will start to pile up more miles. I know the 650s easily go 50-60,000 miles and some are over 80,000 but just haven't heard any big mileage 200s, yet.

I just turned over 19,000 miles on my 2007...only needed oil/filter changes, sprockets and chain and tires. Runs like a top.
__________________
Canuck76
2006 BMW R1150GSA
Eventually, socialists run out of other peoples' money
canuck76 is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not 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 On

Forum Jump


Times are GMT -7.   It's 04:36 PM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014