Service Honda- 2013 KX500AF Build Project
- Thread starter mtn-doo
- Start date
S
snorider99
New member
How much fuel do you burn in a typical day?
M
mtn-doo
Well-known member
I have the stock 1.9 gal. 250F fuel tank and the 3 gal. gas can on my tunnel. I always come home with left over gas and estimate that I burn about 10% more than a 450 4-stroke. Very close on the fuel burns, not a concern for a full day ride.
M
mtn-doo
Well-known member
Interesting observation this weekend. We all ride in deep cold pow this time of year; our best intake mod's are a huge improvement but will still gather some frosty "fuzz" on the filter. No more filled air boxes with snow!!! What I observed; is as air is restricted on EFI four strikes, Carbed four strokes, Two strokes, etc.... they are all victims of the same reduced air flow. As air flow is reduced throughout the day in deep, cold pow, the fuel commands stay the same; the end result is "less air" but the same amount of fuel = a rich condition. We see it everyday on ALL bikes. What I discovered was the APT Smart Carb proportionately reduces fuel; as air flow is restricted, air/fuel ratios stay the same, even with a partially restricted filter. After a day of pounding the pow, my filter was not plugged and my air box was empty, but I had that frosty coating covering my filter. I know my CFM volume was reduced but I ran the same EGT's and crisp power as before. I observed the Smart Carb truly kept air/fuel ratio's spot on, even with a partially blocked filter. Nothing has done that before. Everything get's rich on the second half of the day. It was interesting to see the effect of this system in a situation we had not planned on testing. It apparently will reduce fuel to keep the ratio set. Restrict the filter or what ever happens that reduces air flow, the Smart Carb will adjust fuel delivery to keep the mixture correct. That was soo amazing. By the end of the day with a "plugged" powder filter, my EGT's were still in the high 1100"s as previously set. I know my air flow was about 30% reduced by then, but fuel was reduced equally and I ran spot-on. Wow!
By the end of the day, I lost my idle. It would start in one or two kicks but I needed to blip the throttle to maintain Idle; The rest of the throttle was spot-on. I pulled my intake boot off for a peak inside. There was a frosty coating in the mouth that messed with my Idle. I will design a heat source and test it. It does have a jacket keeping snow off of it, but adding a little heat would take care of the Idle on those extreme days. We started the bikes at 12 above zero, cold soaked and My Smart Carb bike started on the second kick. We were there for an hour getting everything started, Very tough conditions for anything. The others were all 4-stroke EFI's. With a blanket covering the bikes, and the exhaust from a trusty diesel truck as a pre-heater, we got everything running. I would love the opportunity to test this Carb on a current model 450F; I am very curious!? I have learned that most people don't realize that the simple "EFI" systems on our typical current bikes, do not correct for altitude. They only have a programmed fuel map in the ECU and a temperature probe in the intake boot that feed's temp info to adjust for "temperature only", not altitude. A system that corrects for temp/ altitude, "density altitude", like our "smart systems" do, would be the ideal. The APT compensates for Temperature and Altitude both, without the need of an ECU, fuel map, or temp probe. Pretty impressive.
I lost a spring in my kick starter Sunday Morning; Parts arrive Tuesday. A Major OEM Demo again this weekend and I will post updates.... Also getting the "New" prototype unit very soon, possibly this week!!!
By the end of the day, I lost my idle. It would start in one or two kicks but I needed to blip the throttle to maintain Idle; The rest of the throttle was spot-on. I pulled my intake boot off for a peak inside. There was a frosty coating in the mouth that messed with my Idle. I will design a heat source and test it. It does have a jacket keeping snow off of it, but adding a little heat would take care of the Idle on those extreme days. We started the bikes at 12 above zero, cold soaked and My Smart Carb bike started on the second kick. We were there for an hour getting everything started, Very tough conditions for anything. The others were all 4-stroke EFI's. With a blanket covering the bikes, and the exhaust from a trusty diesel truck as a pre-heater, we got everything running. I would love the opportunity to test this Carb on a current model 450F; I am very curious!? I have learned that most people don't realize that the simple "EFI" systems on our typical current bikes, do not correct for altitude. They only have a programmed fuel map in the ECU and a temperature probe in the intake boot that feed's temp info to adjust for "temperature only", not altitude. A system that corrects for temp/ altitude, "density altitude", like our "smart systems" do, would be the ideal. The APT compensates for Temperature and Altitude both, without the need of an ECU, fuel map, or temp probe. Pretty impressive.
I lost a spring in my kick starter Sunday Morning; Parts arrive Tuesday. A Major OEM Demo again this weekend and I will post updates.... Also getting the "New" prototype unit very soon, possibly this week!!!
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mtn-doo
Well-known member
I am working on a test now. I will report back. An area for a Boss to drill and install a heater would be Ideal. I will find out.
S
snorider99
New member
any new videos from the weekend?
sun in the flathead?? lies!! lol definately get some video, the 500 makes me want to boost a 450 as she really gets up and screams!
R
Rush44
Well-known member
See, now you HAVE to. Problem is, we have to stop having fun for a few minutes and pull the camera out. No fun!
Where tp
Where u gonna ride at this week
Where u gonna ride at this week
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mtn-doo
Well-known member
Hey everybody, time for an update. After a lot of hard riding the last two weeks I have a lot of one on one to report. Other than a kick starter repair, It has been awesome. The APT Smart Carb has not been touched and the bike run's spot on regardless of altitude or temperature. The Power and Performance of the big 2-stroker is a whole level above the 450-4 strokes. I can pull a whole gear higher in all conditions, and I am geared "up" as well. The "monster" is truly a hot rod. We have tested a lot of things to learn as much as possible about what is needed to make one of these, or any other 2-stroker perform well and consistent as a snow bike. I have decided to put a list together and report on the findings. I will not list the things like foot peg's and bar risers etc. Those are rider feel and style preferences.
#1 - EGT Gauge, - not necessary but helpful in dialing it in and monitoring.
#2 - Header Wrap, - not necessary but helps keep temp in the pipe and quickly heat the pipe for clean, lean performance.
#3 - Carb Jacket, - recommended. This keeps the constant pounding of snow off the carb. In spring conditions it will not be as important, but a good recommendation for over all consistency.
#4 - Carb Heat, - Required. In very cold conditions, carb heat was "not" needed all day. The very cold air is dry and far below the freezing and sticking point. The bike ran perfectly with no neat in very cold conditions. In the 20's and above, on cloudy days with high humidity, carb heat is needed to prevent icing in the throat.
#5 - Standard Carb, - Works perfectly as a conventional carb. Jetting is required for your riding area. Once jetted a little lean at the parking lot, it is trouble free all day on the mountain.
#6 - Inteli-Jet, - not mandatory but an advantage. Makes adjustments for temp and altitude very easy without the need to re-jet.
#7 - APT Smart Carb, - This is the single best accessory you can invest in. This makes air/fuel issues a thing of the past. You simply set the metering rod, then Altitude "and" Temperature are taken care of. It performs spot on, all day, any Temp and any Altitude. EGT's and performance are consistent. The current EFI 4-strokes don't even do that! Very impressive.
#8 - Snorkel style intake, - optional. The stock intake works perfectly with a snow filter if you remove the bottom of the air box giving the snow a place to evacuate.
I need to address the EFI/Carb topic. We need to understand that the simple EFI units are no different than a Carb. They have a set fuel delivery but will adjust for temperature only. Not altitude. That actually hurts performance. An EFI unit will "add" fuel because of colt temps. Adding fuel while we ride at high altitudes compounds the problem. That is why EFI bikes are using "tuners" and "programmers" to adjust fuel requirements. People afraid of Carb's because of jetting requirements don't understand and are missing out on huge performance advantages. EFI needs the same jetting requirements. That is done with a tuner or programmer. A Carb is done with jet's. There's no advantage either way. I have started my bike in one or two kicks while watching a "non corrected" EFI bike kick and kick to start and idle. Weather EFI or Carb, they "both" need corrected for temp and altitude to be correct. My point is; people with a "carb" should NOT be discouraged. We have a company "pro-rider" and two others "pro class" riders that pull away from everyone else riding every make and model out there. Trouble free and spot-on all day. You have seen them on you-tube,
. They are all riding "carburated" bike's. Anyone wanting to dial in their bike, carb or efi, don't be discouraged. They both work exceptionally well. EFI, you need to "jet" using a programmer, Carb you need to "jet" using jet's. APT Smart Carb or a "closed circuit" EFI need no tuning or adjusting, regardless of the stroke. 2 or 4.
The characteristics of a big aggressive 2-stroke is different for sure. They have a personality all their own. They have massive horsepower, very aggressive, and will make your ride a different experience! Torque has been a question. Service Honda has the chart's. A 500CC two stroke will produce twice the torque as a current 450F, at only 3000 RPM! They are a torque monster and an aggressive HP monster for those who want a hot rod.
As I get time, I will be posting video's.
#1 - EGT Gauge, - not necessary but helpful in dialing it in and monitoring.
#2 - Header Wrap, - not necessary but helps keep temp in the pipe and quickly heat the pipe for clean, lean performance.
#3 - Carb Jacket, - recommended. This keeps the constant pounding of snow off the carb. In spring conditions it will not be as important, but a good recommendation for over all consistency.
#4 - Carb Heat, - Required. In very cold conditions, carb heat was "not" needed all day. The very cold air is dry and far below the freezing and sticking point. The bike ran perfectly with no neat in very cold conditions. In the 20's and above, on cloudy days with high humidity, carb heat is needed to prevent icing in the throat.
#5 - Standard Carb, - Works perfectly as a conventional carb. Jetting is required for your riding area. Once jetted a little lean at the parking lot, it is trouble free all day on the mountain.
#6 - Inteli-Jet, - not mandatory but an advantage. Makes adjustments for temp and altitude very easy without the need to re-jet.
#7 - APT Smart Carb, - This is the single best accessory you can invest in. This makes air/fuel issues a thing of the past. You simply set the metering rod, then Altitude "and" Temperature are taken care of. It performs spot on, all day, any Temp and any Altitude. EGT's and performance are consistent. The current EFI 4-strokes don't even do that! Very impressive.
#8 - Snorkel style intake, - optional. The stock intake works perfectly with a snow filter if you remove the bottom of the air box giving the snow a place to evacuate.
I need to address the EFI/Carb topic. We need to understand that the simple EFI units are no different than a Carb. They have a set fuel delivery but will adjust for temperature only. Not altitude. That actually hurts performance. An EFI unit will "add" fuel because of colt temps. Adding fuel while we ride at high altitudes compounds the problem. That is why EFI bikes are using "tuners" and "programmers" to adjust fuel requirements. People afraid of Carb's because of jetting requirements don't understand and are missing out on huge performance advantages. EFI needs the same jetting requirements. That is done with a tuner or programmer. A Carb is done with jet's. There's no advantage either way. I have started my bike in one or two kicks while watching a "non corrected" EFI bike kick and kick to start and idle. Weather EFI or Carb, they "both" need corrected for temp and altitude to be correct. My point is; people with a "carb" should NOT be discouraged. We have a company "pro-rider" and two others "pro class" riders that pull away from everyone else riding every make and model out there. Trouble free and spot-on all day. You have seen them on you-tube,
. They are all riding "carburated" bike's. Anyone wanting to dial in their bike, carb or efi, don't be discouraged. They both work exceptionally well. EFI, you need to "jet" using a programmer, Carb you need to "jet" using jet's. APT Smart Carb or a "closed circuit" EFI need no tuning or adjusting, regardless of the stroke. 2 or 4. The characteristics of a big aggressive 2-stroke is different for sure. They have a personality all their own. They have massive horsepower, very aggressive, and will make your ride a different experience! Torque has been a question. Service Honda has the chart's. A 500CC two stroke will produce twice the torque as a current 450F, at only 3000 RPM! They are a torque monster and an aggressive HP monster for those who want a hot rod.
As I get time, I will be posting video's.
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mtn-doo
Well-known member
Yes, They are looking at the possibilities. They have a couple very practical ideas. I will keep you posted. The new proto type will be installed next week!
M
mtn-doo
Well-known member
My Trail Tech water temp stay's in the 130F to 150F range all the time. Last weekend at 16F above zero, in deep pow all over the motor all day, stayed right on 130'ish. On hard packed roads, it stay's right on 150F. On warmer ambient day's in the upper 20's and 30's, it stay's between 130F and 150F. Very consistent. I was surprised that there were no big changes regardless of ambient temps or snow conditions. I feel it is the perfect temp range for a two stroke. Interesting note; these temps are with a 160F thermostat, so it looks like engine temps will stabilize about 20 to 30 degrees "less" than your selected thermostat. With dual 50's, you should be consistently in the 100 to 110F range.
M
mtn-doo
Well-known member
I know, I know.... It is very exciting and hard to wait. We want pictures of all the details and info together. Next week it will be done. Everyone needs to remember, this is only a "prototype" to show the possibilities. Timbersled Products is constantly testing ideas and developing products that will "possibly", "some day", be incorporated into production models. This will not be a sneak peak of anything released this year.