Wheres APT Smartcarb ?

Check out the "roost monster " videos and others of the same KX500 AF. Starting, idling, WOT, etc. It was an amazing monster. Ive never had a more perfect running bike. The 40MM Smart Carb ,and her engine build and tune were incredible. Miss her badly. I'm doing a second for a friend. can't wait. I will post along the way. Several projects underway.

I have an idea. .... sumboy , you asked where APT and the company has gone. Answered X times. The rest is a personal thread for your. ...? You finally got your bike running? Be happy now and go ride !

The end....

Mtn-Doo,
I'm under the impression that you do something other than build and tune engines for a living, I don't share the same experience.
Having "never adjusted" your smartcarb since setting it immediately shows your ignorance in finding the proper initial tune.
The carb can be adjusted to a richness that would basically blanket your experience, but to be set properly will find it requiring adjustment every 10 degrees for certain.
I'm interested in your multiple states, elevation and temperature comment, seems fairly ignorant of you to not recognize it was outside of optimum adjustment.
"pro's", well I'm no pro in any of the riding but I do hang out with one who's mx track is beside my driveway. Beyond that I've seldom seen a pro who is also the lead tech for the team.

I know that Summitboy's system wasn't the only one to "not run very well", The engine is a package very similar to many I have assembled before with the carburetor being the limiting factor. I have had many many SC users contact me about how to get theirs adjusted as well as how mine was in my youtube videos. I've recommended the settings I had settled on and not one has resulted in the same experience. Lets get that clear now, not 1 other rider in similar altitude, temp or humidity has had the same requirement when set on the same engine arrangement. Not one of the carbs has "compensated" its adjustment to buffer for the minute difference. Thats a 100% difference in requirement.
I worked at sealing the carbs with sealed shrink tube at the throttle cable opening, different sealant on the choke knob and several other little things that may have been an issue to the point of buttering the exterior of the gasket surfaces with threebond to make it air tight. I did not change anything with this.

I do need to admit that I know if 1 guy, thee guy with a SC who says its the best thing ever. I only know him by forum and have absolutely no idea what he is doing with it and have never seen a photo to prove he even has one haha.

Starting the smartcarb, where the hell did the primer bulb idea come from. Can't have only been 1 guy looking at the issue. Was it tip valve related? I don't know, but I remember that fad blowing through here also.

The "break in", or wearing of the components to settle into a comfortable fit was something else too. Why not have that process accomplished at the factory while its being final tested.

Corey,
You don't recall the conversations but I'm certain that if I can dig up ancient imessages or maybe fb messages that I can find our conversations about reversion entrapment, elimination of the reed pedals, and probably some of the drawings i'd shared.
I had no idea what you were up to or that you had this other gig going until your FB link I opened today and hey, there is exactly what we'd been talking about and not just one time either. :tsk:

Hurry up and get it ready, I haven't got the abilities to fabricate it how it needs to be, YET, but you know that is exactly what i was in the pursuit of. Ron will be fairly excited to see it also since he and I had also had the same conversations. I'm expecting a buddy with a 3d printer to start getting me some better pieces to bench test with, but nothing that would hold up to working within the engine.

Roostius_Maximus said:

Corey,
You don't recall the conversations but I'm certain that if I can dig up ancient imessages or maybe fb messages that I can find our conversations about reversion entrapment, elimination of the reed pedals, and probably some of the drawings i'd shared.
I had no idea what you were up to or that you had this other gig going until your FB link I opened today and hey, there is exactly what we'd been talking about and not just one time either. :tsk:

Hurry up and get it ready, I haven't got the abilities to fabricate it how it needs to be, YET, but you know that is exactly what i was in the pursuit of. Ron will be fairly excited to see it also since he and I had also had the same conversations. I'm expecting a buddy with a 3d printer to start getting me some better pieces to bench test with, but nothing that would hold up to working within the engine.

Click to expand...

Well dig up them ancient messages.

Actually I remember I enjoyed many conversations with you. For a fact though you never shared any drawings with me. I do recall one conversation that you said you were working to improve the pulse and shared a few rough ideas, nothing to the level you describe. I have nothing to hide and honestly didn't know you had laid claim to a Tesla valve designed to work on a two stroke. Everybody knows I have worked with two strokes and sound waves for years and have a need right now for just such a device on our SonicFlow engines. Sorry to beat you to the punch. BTW we are already testing ours and can tell you it's much more difficult than it looks.

You are pretty bold about laying claim, but in this case the concept is far from novel and certainly did not start with you or me. Nearly 30 years ago Edmonston patented (US 4980097 A) his air reversion device.

http://www.google.com/patents/US4980097

George Boswell also toyed with something very similar he called a Supercycler.

Even further back, my other hero besides Tesla, Michael Kadenacy was using a reed-less intake valve on his Implosion 2 stroke engines. It can be seen here: http://www.aircaraccess.com/images/kadnac01.gif

I'm still unsure what you guys are trying to prove, but seeing's how you have called me out here. How about we share our considerable experience with these good people and let them know what to expect about these "new" valves?

On another note there are actually quite a few CR500's out there running flawlessly now with their SmartCarbs and we are selling Rev H billets here and there for new AF snowbike builds. Now that we have started to understand the airboot issues more and problems related to some of the aftermarket or modified heads that just don't do well with finely atomized fuel, it's showing to be a nice addition to the five hunnies. Also I offered to buy back your unwanted SmartCarbs and reached out to find out what was happening but that was when you quit talking to us. Tried to make it right with you friend and you know it.

Roostius_Maximus said:

but nothing that would hold up to working within the engine.

Click to expand...

The new benchtop thermal plastic 3D printers have a thermal setting fiber reinforced plastic that you can use. It sets up looking a lot like the phenolic plastic that V Force uses. It will hold up inside. The length has to be a lot longer to get adequate reversion distance, and puts the material a lot closer to the piston, but with no reeds to break its ok. Also diminishes some runner volume normally associated around the reed cage and the shorter 1.8" reed petals.

I'll dig, I know we'd conversed about it and I'd had to explain what i was attempting to describe with a drawing, I'd also recently deleted anything older than 2015 since the 5gb of icould storage was almost jammed just from Imessage content.

I'm not laying claim to it, but expected a "hey, check this sh1t out" kinda message figuring you'd have recalled at least that we'd talked about it.

I'm not a company to produce a product like that, nor am I outright laying a claim, so beating me to the punch is of no concern, get in there and get it happening! I'm enthused!

I'd for one talked about a very similar intake and had drawings, and another where we discussed an idea i had to open the existing reed like a clamshell after idle duty, surely you recall this after we talked about how to eliminate as much mechanical apparatus as the drawings implied were required.

Its not a big deal to me or I wouldn't mention anything of it here.

Back to the APT 3/4 lean spot, we know we talked about that and only decided to buffer it with octane, that aspect of things I was not thrilled with, but it saved the piston from certain destruction. I know everyone I've spoken with about the s/c has contacted me for the same solution. If Mtn-doo hasn't had this issue I'd more than willingly try the identical carb and be hopefully be proved wrong.

Roostius_Maximus said:

I'll dig, I know we'd conversed about it and I'd had to explain what i was attempting to describe with a drawing, I'd also recently deleted anything older than 2015 since the 5gb of icould storage was almost jammed just from Imessage content.

I'm not laying claim to it, but expected a "hey, check this sh1t out" kinda message figuring you'd have recalled at least that we'd talked about it.

I'm not a company to produce a product like that, nor am I outright laying a claim, so beating me to the punch is of no concern, get in there and get it happening! I'm enthused!

I'd for one talked about a very similar intake and had drawings, and another where we discussed an idea i had to open the existing reed like a clamshell after idle duty, surely you recall this after we talked about how to eliminate as much mechanical apparatus as the drawings implied were required.

Its not a big deal to me or I wouldn't mention anything of it here.

Back to the APT 3/4 lean spot, we know we talked about that and only decided to buffer it with octane, that aspect of things I was not thrilled with, but it saved the piston from certain destruction. I know everyone I've spoken with about the s/c has contacted me for the same solution. If Mtn-doo hasn't had this issue I'd more than willingly try the identical carb and be hopefully be proved wrong.

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Yeah, I never did see any drawings, but I remember you clearly describing your idea of a retractable reed block to start opening everything up after idle and resonances took over. Could be a great idea and I of course was interested in seeing your drawings because I was having a hard time understanding the mechanism.

It was clear you were frustrated and had given up on the SC and frankly I didn’t think you had any further interest so I didn’t show you what I was doing.

We’ve had ongoing issues with aftermarket heads, mostly KTM’s. To the best of my ability to describe it, aftermarket head manufacturers or company’s modifying heads are working within the parameters of conventional fuel systems and wet mixtures. You know that there is a target MSV or squish velocity that we are after, somewhere between 15 and 30 meters per second, depending on the bore size and fuel selection.

Here’s what I believe is happening; the finer atomization of the metering rod carb speeds up the burn rate and induces a hotter burn. It’s now fairly clear (again depending on the fuel) that certain head mods which increase compression and inadvertently speed up the max squish velocity will over-turbulate the finer fuel mist/mixture enough to cause rough running and other harder to describe issues. This is not necessarily you Roosty, so don’t take it personal, however the SC in most cases gives the gains and more you would otherwise expect from your modified head, so in most cases best left alone, or modified fully understanding your target MSV and the difference a 10% hotter burn will imply.



The leaning out problems on the top end with the CR 500’s are mostly related to too restrictive of an airboot and the scoop vents can’t get a good read on MAP and therefore can’t increase fuel flow proportional to air/flow through the carburetor. This always shows up on the top end, because of not a strong enough ram pressure into the scoop and hence pressure against the fuel in the float bowl.

The same detonation issues Smokey Yunick ran into on the hot vapor engine with what I'm guessing was a similar atomization when naturally aspirated, maybe we all just need to add a turbo.

heat an fuel

Thanks for all the diligent typing and emotion sharing and some tuning insights. I like to open this thread, I can usually feel the heat steaming off my computer as I go through the posts.

You gotta know:
1 no two engines are the same or respond the same
2. no two expert riders always feel the same tuning changes
3. race teams in MX/NASCAR and others know the best riders and testers CANNOT ACURATELY feel changes less that 10%, engine or suspension.
4. so when you refine gas delivery to closer to perfect , you will know or be killed by DETONATION
5. when you don't have a dyno, many then don't believe in them, every good engine we have bought was born on a dyno while someone searched for some good compromises and reduced detonation.
6. the best two stroke engines I ever blipped a throttle on were dyno tuned, and embarrassingly smooth and felt maybe " weak" while they turned out to have superior runaway hp and made me want to cry of frustration because I couldn't get there.
7. I want to thank you all again for these posts as I have filtered out some good tidbits of information, and hope I will remember their value as I also fight with and try to improve on fuel delivery to my toys.

I think I might be the one guy Roosty is talking about with the working SC. Don't know that I'd say it's the best thing since sliced bread, but hey, what invention on this earth really is better than sliced bread? I mean come on! Pre-sliced bread is pretty cool! Lol.

Back to the subject. I never buy into hype on a product, I just don't do it. I don't buy stocks either cuz I don't gamble. What I do buy into is product support and customer service. APT took great care of me when my buddies and I bought 3 of the billet 40mm. Corey took great care of us after the split and modified our carbs to get rid of issues. As long as that keeps up and the carb keeps working for me, I'll stay a customer. That is unless something else comes out that works better for me. Technology is always changing.

FYI, my carb is on an AF500 with a timbersled in the winter, and I ride the bike on single track in the non-winter months. Best woods bike EVER!

Prior to sending the carbs back for modifications, I had to use starting fluid the first start of the day whether is was cold or hot out. after that it would start 1st or 2nd kick for the rest of the day. Now it starts first kick every time! I can definitely attest to the fact that since installing my SC, I use WAY less fuel on a day of snowbiking, hands down. I can also attest that it does meter accordingly with altitude changes. My bike will also idle all day long. That was the first thing I noticed right away when I installed the SC. I expected it to die, but it didn't. I took my time putting my gear on while it idled just to see what would happen. It never died.

The one myth I'm not buying is the "set it and forget it". I do have to mess with the adjuster between snowbike season and single track dirt riding. While it compensates for altitude just fine for me, it doesn't seem to compensate for vast temperature differences. I'm totally fine with that. it was the altitude compensation, idling, and easy starting I was hoping to gain with the smart carb. Couldn't get my Keihin to do any of those things, even with a dial a jet setup on it.

I'm no genius like Roosty or Corey, but I do have a fairly extensive technical background and am quite in tune with how my bike is running. I don't typically involve myself with these types of forum posts other than to read, but I felt it necessary to put my positive experience out there as most only put it out there when it's negative. My only hope by posting is that maybe gains/advances can be made in the technology using my input. I'm sure not smart enough to do it, so maybe my input and experiences will help

I'd also like to give a shout out to both Roosty and Corey. Both you guys have been great to me and I love the info You've both shared with me

This has gotten a bit bashy...

I appreciate everyone's opinions in here, but this isn't the place to do battle. this thread was about Where APT went. Now we know.

If what Corey posted is true, i will give him props for how handled getting out of APT.

As for the product itself, i'd sure love to see an SC with a proper company supporting it. As i noted before, my Beta 300 runs epic with the carb. I couldn't be happier with runablility. Fitment is rough with the Billet, but performance is insanely good. Just got back from a 43 mile single track ride. used 1.25 gallons, and that's with some really fast open sections. Stoked!!!

mrquick68 said:

This has gotten a bit bashy...



I appreciate everyone's opinions in here, but this isn't the place to do battle. this thread was about Where APT went. Now we know.



If what Corey posted is true, i will give him props for how handled getting out of APT.



As for the product itself, i'd sure love to see an SC with a proper company supporting it. As i noted before, my Beta 300 runs epic with the carb. I couldn't be happier with runablility. Fitment is rough with the Billet, but performance is insanely good. Just got back from a 43 mile single track ride. used 1.25 gallons, and that's with some really fast open sections. Stoked!!!

Click to expand...

Agree with all said... Time to move on it is a carb for god sakes ... Buy what you want ...


Sent from my iPhone using Tapatalk

Well I won't get that hour back.....Corey was very good to me, as was randy, if the carb worked as well I would be elated. On a dirt bike not held wide open the smarty is good IF you remove the tip over balls and vent the float bowl to the air box. The air??Scoop?? Does nothing for float bowl pressure, vacuum. Epa compliant carb maybe, but without that the tip over balls just cause problems. I spent over two seasons chasing my tail, this season I will ride. I have a 38 lectron on my 300 ktm and a 36 lectron on my gas gas we had the cast smarty on. My opinion, which is worth not much, is I bought the 300's because they are so light and fun to RIDE. Carbs have less things to go wrong over Efi so I will be flying around on both with the 3-3 needle installed. I won't put the highest mark, but I will have the biggest smile.

summitboy said:

Id love to hear why Gas Gas dropped them. Im guessing hard starting, flooding, inconsistant performance and premature wear.

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We ran tests on the SmartCarb at the GasGas factory in Girona Spain in late 2011. During testing the 38mm billet SC on a 2012 EC300 showed a 14% improvement in HP and nearly an 8% gain in torque. They later claimed during a year of independent testing that they were also seeing as much as 50% improvement in fuel economy.




This is not the actual dyno chart, as I can't seem to find it today, it has been posted on GasGas riders forum. Anyway this is very similar to what we see on just about every two stroke.

The second time we were there we ran the bikes at Jordi Figuera’s ranch, GasGas admitted to us that they were having trouble with their new airbox. If you look closely in the picture you will see a rectangular compartment near the number plate on the outside of the airbox.




They had designed a cartridge style air filter for quick access, but it leaked like crazy. So after a day of ingesting large amounts of dirt through the engine (and carburetor) we flew back home and GasGas announced a recall and delayed production while they went back to the previous airbox/filter arrangement. Near this same time was when the tsunami hit Japan, so later when GasGas was finally able to pull it all back together and make another run late 2012, they couldn’t get enough carburetors from Keihin because of the flooding at the factories. KTM and others had depleted the inventory. GasGas was forced to source carburetors off the shelf and I spoke with the lady they hired to scour the US for carburetors and she told me that of the bikes delivered in 2012 they could come with either a round cap PJ Keihin, and ASI or if you were lucky an ASII air stryker Keihin… Suffice it to say it was a disaster. After GasGas restructured, we met again in 2013 at the EICMA motorcycle show in Milan with Ramon Puente, then President of GasGas, they were very excited about the SmartCarb program and committed to an order of 3,000 units of the cast 38. Less than a year later, they filed for bankruptcy protection and sold their debt to the Spanish Bank, who in turn sold it to an Israeli group.

Last summer, after burning up a bunch more money they halted production again. In desperation they put the factory up for sale and then when KTM went to pay them a visit they hung a burning effigy (with a KTM shirt on) outside their corporate HQ’s. That’s what greeted Mr. Pierer when they showed up. This distasteful act and several other foolish business moves makes me believe that we will not be hearing much more about GasGas. At least on the Enduro end, I do hear rumors of the Trials program continuing and some tricky gearboxed electric trials bike ready to make a debut.

Cyl Head and Elevation

I think elevation has something to do with performance of the smartcarb and porting of cylinder heads.
Most of you guys are riding at 2000 ft or lower elevations = higher air pressure.
For most of you in the mountains above 4000 ft, well the air pressure is going to be low anywhere in north america.
I have a 2015 KTM XC-W and its been challenging to get running sharply as the CR500 I had.
2015 300XC-W storey:
The stock bike had a 165 main jet, I now have a 157 main and it still too rich.
The stock bike had a N8RG needle, the third I am trying is the leanest NECJ.
The stock bike had a 38 pilot jet, i have a 35 pilot at 3.5 turns out on Air Screw.
The stock bike had a 7.0 slide, I have an 8.0 slide in it now.
This bike is still not crisp enough but getting better.
What these huge jetting adjustments on the new 300 XC-W tell me is that with Roostius Maximus's porting on my CR500 I had may have been too much volume (low compression) for the 6000 ft mountains with dry air I ride in. Roosty's at 700 ft elevation. Roosty's smartcarbs would also start in a couple kicks.
Now the CR500 ran pretty damn good with a 38mm PWK but I don't think it had enough compression with Roosty's head mods.
Now with a 38mm Smartcarb on it, the CR500 never started once in less than 40 kicks . Would more cylinder head compression have helped? Who knows.
All I know is KTM SX heads are higher compression for higher elevations.
Seems to be the consistent storey I am finding over 6000 ft in dry air conditions. That might possibly apply to most of the riders Chris is familar with having SC not working.
My thoughts,
Patch

Patches88.... Couple things. First, you should probably have a 40 mm smart carb for a 500. Second, it takes 1 million kicks to get it started because you need to send it back to them for modification of the choke circuit and the check valves. I sent mine back for those modifications and now my CR 500 starts first kick

Rolling20s said:

Patches88.... Couple things. First, you should probably have a 40 mm smart carb for a 500. Second, it takes 1 million kicks to get it started because you need to send it back to them for modification of the choke circuit and the check valves. I sent mine back for those modifications and now my CR 500 starts first kick

Click to expand...

Been there, done that, all of it. Corey & Roosty recommended the 38mm. I had to send mine back, Corey returned my money and apologized for the problems it had. I put too much money into it buying $thousands in new ignitions trying to make it work. I put a lot more than $800 US into it.

Yeah, well, when they were still APT Tom recommended I get a 40 mm billet. As per Roosty, I have the only one that works. Probably because I have a 40 mm and everybody else with a 500 is using a 38mm cast and the 500 needs a 40mm. All I can say is mine works great.