Fuel/air mix strategy for TAT ride?
#21
11-01-2019, 09:52 PM
Join Date: Mar 2015
Location: Va Beach
Posts: 333
I once told you I'd be your friend for life if you would remove your public references where you instruct peeps to install wire (coat hanger, etc) onto the exhaust cam, on the KACR flyweights..
..
On to the subject of jets: I rode to work on new jetting: 40-148, 1N, changed from 35-144,2N.
Results: Bike sounds louder, warms up faster, and is smoother running, pulling 6th gear at 3krpm whereas it used to not run smoothly much below 4krpm.
No clue on fuel economy yet but I can got to 6th gear at lower speeds. WOT at 82 mph indicated and she was accelerating well for that speed. This is on flat ground with a headwind. Can probably get 90mph on a flat road no wind. Maybe more, but don't care, that is what my Triumph is for.
#23
11-02-2019, 12:52 AM
Join Date: Mar 2015
Location: Va Beach
Posts: 333
Feels like a little more power but not much, or maybe I am jaded from riding my 1200cc 96HP/83 lb-ft Triumph. Less than a similarly sized Ducati Monster but the most power I have had between my legs. But I am easing into it a little following carb work and since I can't seem to clean the fork oil out of my contaminated front brake pads I am holding back. Without tire lifting brake torque I am riding on the conservative side. Need new brake pads to replace the barely used oily ones.
#24
11-02-2019, 02:53 AM
Roger that..
Interesting that you noticed the change in the exhaust note.. That is also "as expected", a very "real" aspect of a lidless CVK recipe..
Interesting that you noticed the change in the exhaust note.. That is also "as expected", a very "real" aspect of a lidless CVK recipe..
Last edited by Klxster; 11-02-2019 at 02:59 AM.
#25
11-02-2019, 04:27 PM
BTW,
Remind me which needle you are using..?
While top speeds with the 351+lidless setup is not known, 250's + Full performance exhaust (E.G. FMF Mega/Power bomb and FMF slipon) + Lidless setup "#2" will do 100+ mph with stock spraughkets .. If you need this top end "headroom" for your trip, do-up a header for the Leo Vince - assuming the Leo will mate properly to one..
Remind me which needle you are using..?
While top speeds with the 351+lidless setup is not known, 250's + Full performance exhaust (E.G. FMF Mega/Power bomb and FMF slipon) + Lidless setup "#2" will do 100+ mph with stock spraughkets .. If you need this top end "headroom" for your trip, do-up a header for the Leo Vince - assuming the Leo will mate properly to one..
#26
11-02-2019, 05:05 PM
On the lidless airbox deal, I encountered a different comment/observation Thursday while assembling a couple of new motorcycles at the shop I used to work at part time. I just started back doing a little part time work there again.
I was assembling the new 2020 KLX300 and commented to the service manager that even the airbox lid and filter looked just like my '06 KLX250S while I was servicing the air filter with BelRay. I joked about how restrictive the opening was, as it was the usual tiny slit in the rubber intake boot to reduce noise. I told him I'd remove that and cut out some of the lid opening if it was mine.
He commented that that would screw up the operation of the CV carb on the older models...the new 300 is FI. I kind of argued that point with him, that I think he was getting that opinion from the days when many replaced the whole airbox and boots on the inline fours that had CV carbs. The older inline fours with simple slide/linkage carbs worked fine with those K&N individual filters, but indeed the funky air around the filters on the later CV carb models could occasionally get some weird effect...not always, but sometimes depending on the bike and conditions.
As long as the stock airbox and boot are still in place under the seat/tank, you still have a dead-air space that is relatively unaffected by turbulence. Opening the intake of the airbox/lid won't cause the CV carb to get funky as long as it's jetted appropriately. This guy is pretty knowledgeable, but I think he was off the mark on this one...as long as an airbox is still in place. Yeah, you get the noisy drone at certain throttle conditions without that tiny airbox inlet, but it kind of sucks otherwise IMO on a well modded KLX.
I was assembling the new 2020 KLX300 and commented to the service manager that even the airbox lid and filter looked just like my '06 KLX250S while I was servicing the air filter with BelRay. I joked about how restrictive the opening was, as it was the usual tiny slit in the rubber intake boot to reduce noise. I told him I'd remove that and cut out some of the lid opening if it was mine.
He commented that that would screw up the operation of the CV carb on the older models...the new 300 is FI. I kind of argued that point with him, that I think he was getting that opinion from the days when many replaced the whole airbox and boots on the inline fours that had CV carbs. The older inline fours with simple slide/linkage carbs worked fine with those K&N individual filters, but indeed the funky air around the filters on the later CV carb models could occasionally get some weird effect...not always, but sometimes depending on the bike and conditions.
As long as the stock airbox and boot are still in place under the seat/tank, you still have a dead-air space that is relatively unaffected by turbulence. Opening the intake of the airbox/lid won't cause the CV carb to get funky as long as it's jetted appropriately. This guy is pretty knowledgeable, but I think he was off the mark on this one...as long as an airbox is still in place. Yeah, you get the noisy drone at certain throttle conditions without that tiny airbox inlet, but it kind of sucks otherwise IMO on a well modded KLX.
#27
11-02-2019, 05:35 PM
I once told you I'd be your friend for life if you would remove your public references where you instruct peeps to install wire (coat hanger, etc) onto the exhaust cam, on the KACR flyweights..
But you keep becoming more and more pompous and wise in your eyes. Just sayin' you aren't the only authority. Hell, you even contradict Mikuni on their comments.
#28
11-02-2019, 06:30 PM
KLX678, your right - as usual..
TNC, I only know about the KLX250S - in regards to our application and OEM setup of our CVK32's.. During the year (or so) that I spent "dyno experimenting" with my bike, I had to continually research to understand not only what I was doing, but also, why I was having to do it.. As is usually the case, this knowledge was very hard to "come by". Also, it took me a lot of "meditating" to put the pieces of the puzzle together - If only I were smarter...lol
I seriously doubt that many peeps out there understand that pulling the lid off a KLX250S or a KLX300R exposes, what turns out to be, our huge (non serviceable) MAJ (Main Air Jet) to higher (ambient) air pressure. Which, in turn, causes the AF in the emulsion tube to go extremely lean. And that simply installing "insanely huge" main jets will compensate. It isn't surprising that most "knowledgeable peeps" would only know that certain mods to the intake tract leading to the CVK can cause problems...I mean, who, except an idiot like me, would take the time to research CVK functionality on a granular, system by system, basis ?
In fact, removing the lid causes significant changes in every system/circuitry within our CVK's. Some of the systems can still function properly enough to not need direct "intervention" (Slide functionality, bowl venting, pilot system, etc), while others (main fueling system) need significant modifications. Since I did not want to experiment with multiple components - emulsion tubes, needle jets, MAJ restrictions, etc - I just kept putting in bigger and bigger main jets in hopes that this one component could bring the main fueling system back "up to snuff" as per the dyno AFR readouts.. And this eventually worked, but midrange fueling went too rich. With another stroke of luck, I found that the midrange overfueling could be controlled (well enough) with the stock side spring put back in, in concert with the needle clip set to the top notch.. The lidless recipes aren't perfect, a needle with a custom taper could work better than what we have available, but the recipes are optimal.
From where I am at now, all I can do is speculate on other issues with other applications. One thing (as you know), for instance, is that the airflow into the intake bell of a CVK must be non-turbulent in order for the main fueling system to work correctly..
TNC, I only know about the KLX250S - in regards to our application and OEM setup of our CVK32's.. During the year (or so) that I spent "dyno experimenting" with my bike, I had to continually research to understand not only what I was doing, but also, why I was having to do it.. As is usually the case, this knowledge was very hard to "come by". Also, it took me a lot of "meditating" to put the pieces of the puzzle together - If only I were smarter...lol
I seriously doubt that many peeps out there understand that pulling the lid off a KLX250S or a KLX300R exposes, what turns out to be, our huge (non serviceable) MAJ (Main Air Jet) to higher (ambient) air pressure. Which, in turn, causes the AF in the emulsion tube to go extremely lean. And that simply installing "insanely huge" main jets will compensate. It isn't surprising that most "knowledgeable peeps" would only know that certain mods to the intake tract leading to the CVK can cause problems...I mean, who, except an idiot like me, would take the time to research CVK functionality on a granular, system by system, basis ?
In fact, removing the lid causes significant changes in every system/circuitry within our CVK's. Some of the systems can still function properly enough to not need direct "intervention" (Slide functionality, bowl venting, pilot system, etc), while others (main fueling system) need significant modifications. Since I did not want to experiment with multiple components - emulsion tubes, needle jets, MAJ restrictions, etc - I just kept putting in bigger and bigger main jets in hopes that this one component could bring the main fueling system back "up to snuff" as per the dyno AFR readouts.. And this eventually worked, but midrange fueling went too rich. With another stroke of luck, I found that the midrange overfueling could be controlled (well enough) with the stock side spring put back in, in concert with the needle clip set to the top notch.. The lidless recipes aren't perfect, a needle with a custom taper could work better than what we have available, but the recipes are optimal.
From where I am at now, all I can do is speculate on other issues with other applications. One thing (as you know), for instance, is that the airflow into the intake bell of a CVK must be non-turbulent in order for the main fueling system to work correctly..
Last edited by Klxster; 11-02-2019 at 06:39 PM.
#29
11-02-2019, 07:38 PM
Point is it is no longer a case where anyone can really approach you for any help without getting a lesson as if they are trying to write a master's degree dissertation. You used to give some good information for help, based on your experience. Now you start into all the AFR as if everyone has the instrumentation and the knowledge to use it along with a grand to spend on dyno time. The guys are looking to learn a bit of the information to set up jetting for altitude change. Should they jet richer or leaner for their circumstances.
Maybe someone here can actually help the OP. At this point I'd recommend the OP get with TNC or D Pippin since both have some knowledge they will share without the need for an AFR meter and a dyno. People actually jetted carbs adequately before meters, computers, and dynos. People like Gordon Jennings, Joe Minton, and Kevin Cameron wrote of jetting without AFR meters.
Heck here's one right here... click They don't mention CV or direct cable/slide set up, they do mention two and four stroke pointing out four strokes are less sensitive. By the way the term for non-turbulent fluid flow is laminar. The desirable flow for the intake charge fluid is laminar.
Maybe someone here can actually help the OP. At this point I'd recommend the OP get with TNC or D Pippin since both have some knowledge they will share without the need for an AFR meter and a dyno. People actually jetted carbs adequately before meters, computers, and dynos. People like Gordon Jennings, Joe Minton, and Kevin Cameron wrote of jetting without AFR meters.
Heck here's one right here... click They don't mention CV or direct cable/slide set up, they do mention two and four stroke pointing out four strokes are less sensitive. By the way the term for non-turbulent fluid flow is laminar. The desirable flow for the intake charge fluid is laminar.
Last edited by klx678; 11-02-2019 at 07:43 PM.
#30
11-02-2019, 08:55 PM
Well, Snap asked for information on the subject, on post #14 - so rather than use PM, I just posted it here in case anyone else wanted to travel a path of "CVK enlightenment"... No dissertations are warranted.. I'm sorry I continue to be a disappointment to you..
E10 burn characteristics makes "old school" jetting via plug readings a thing of the past. Unless the old "plug reading" dogs have researched E10 and know it's "tells" on a spark plug, they won't even be able to deduce the tiny bit of info E10 does offer on a spark plug..
Many famous peeps use the latest tech to create best performance: Curly Howard, Eddie Munster, Mr. Ed, Mr. French, Mr. Haney, Sam Drucker, and Chauncey Gardiner..
E10 burn characteristics makes "old school" jetting via plug readings a thing of the past. Unless the old "plug reading" dogs have researched E10 and know it's "tells" on a spark plug, they won't even be able to deduce the tiny bit of info E10 does offer on a spark plug..
Many famous peeps use the latest tech to create best performance: Curly Howard, Eddie Munster, Mr. Ed, Mr. French, Mr. Haney, Sam Drucker, and Chauncey Gardiner..