Just thought I would pass along my thoughts on what better. This is my opinion only with a couple of facts thrown in. I run a sx450 this year, ran a kx 450 fi last year, and my son runs a 06 kx 450 . The carb works great in all conditions. We tried the jd jet kit with the blue needle but the 06 liked the stock needle better. Last year we did some testing with the main jet and running up the same hill run after run and going from a 180, to a 185, to a 195 the 195 produced the most power. We have tried this on othe bikes with the same results so don't be afraid to go big.on the 06, with a frozen boost intake and sock, fmf pipe and silencer, we had a mid range bog with the needle in the stock, center clip position and going two clips rich, raise needle, and going from a 42 to a 45 pilot jet the midrange is awesome. IMO a 08 kx carb is the dream bike. Still carbed but a 5 speed. Now for the fi thoughts, it's great when it works, but IF something goes south your walking....no fuel pump, injection,air temp sensor, cyl. Temp sensor, roll ver sensor ect. Don't get me wrong i love my fi when it works, and most do but when they have a problem, like a short in the wirering loom, it sucks. Also these bikes dump fuel into the motor after about 25 degrees. I run a dobeck controller on my last years bike and now this years ktm and after a few teething pains it seems to be bullet proof. Do you have to run one on a fi bike. Most don't but to have the ability to reduce fuel going by your rings, taking lubrication with it and diluting your oil, I think it's a wise investment for 300-350 bucks. It allows me to ajust my idle fuel with a push of a button and has a closed loop in the midrange and wide open. I have tested different afr's and my bike likes 12 afr wide open for power and by setting my cruise ( yellow mode) at about 13.5 my fuel usage is great going down the trail. So that's my thoughts and what I have found so far. I love the closed loop options and with this controller I can raise when the closed loop turns on so I can see what the stock setting would be without the controller controlling. These controllers have had some problems with water getting into the gauge. But if you thaw out your bike like I do every night I have had no problems. Hope this may help some. Just what I have found so far.....any questions let me know...Garry
Carb or fuel injection
- Thread starter the gman
- Start date
R
Rush44
Well-known member
Good post man. I agree with you on everything except that I felt my bike was spot on cleanest at around 12.5 AFR. Maybe I spent more time at WOT than you but it seemed that if I dropped below 12.5 I would occasionally get some extra decel popping and sometimes the throttle chop response wouldn't be AS CRISP (it was still good, just not that perfect clean response every time). Could 12 pull harder? Very possible.
For me a carb and how to tune it is a mystery. I get the basic idea behind it but I lack the knowledge. Since I'm kinda nerdy as it is I would much rather hook a computer up to my bike or mess with some code to fix issues that are based on numbers I can understand. Should I run a bike in the future with a carb I know full well that APT will be getting a call from me and making a Smartcarb sale.
As with any controller I think it is PARAMOUNT that each person knows how to assemble/disassemble the unit and understand how it draws power. This goes for PCV, Bazzaz, Dobeck, whatever your flavor may be. I fried the lower fuel control module on my first test model and the bike flat out would not run until the injector clip was replaced with stock and the wiring harness was completely removed. I had to do this in the woods all alone by myself. Thankfully I had the tools on hand to complete the job. Take the time to learn how the unit works and how to get yourself out of a jam should something go south. I'm currently trying to learn as much as I can about the electrical system on my 450 SXF.
Also, Dobeck is addressing the gauge fog/moisture issue. I have will have a prototype gauge coming as soon as Chris gets them finished and I will report on it's performance.
For me a carb and how to tune it is a mystery. I get the basic idea behind it but I lack the knowledge. Since I'm kinda nerdy as it is I would much rather hook a computer up to my bike or mess with some code to fix issues that are based on numbers I can understand. Should I run a bike in the future with a carb I know full well that APT will be getting a call from me and making a Smartcarb sale.
As with any controller I think it is PARAMOUNT that each person knows how to assemble/disassemble the unit and understand how it draws power. This goes for PCV, Bazzaz, Dobeck, whatever your flavor may be. I fried the lower fuel control module on my first test model and the bike flat out would not run until the injector clip was replaced with stock and the wiring harness was completely removed. I had to do this in the woods all alone by myself. Thankfully I had the tools on hand to complete the job. Take the time to learn how the unit works and how to get yourself out of a jam should something go south. I'm currently trying to learn as much as I can about the electrical system on my 450 SXF.
Also, Dobeck is addressing the gauge fog/moisture issue. I have will have a prototype gauge coming as soon as Chris gets them finished and I will report on it's performance.
I agree fully with what is stated. I personally run a 07 kx450 and runs spot on all the time. I also run an engine cover and trail tech temp gauge and believe keeping good engine temp is key. I run a stock air box sealed up tight like a frogs arse and frogskinz on the #plates and that seems to be working well for me too. Also I have a pro circuit ti4 pipe and like that too as it is a lot quieter than stock. All in all I like the simplicity of the carb bike vs the fi but that's just personal opinion.
M
mtn-doo
Well-known member
Hey Garry and all, great thread. There is no question, a carbed bike is more consistent and better in engine performance, period. No fuel/oil issues, and more HP than EFI. Folks are not sure about jetting a conventional carb. It is easy and fast, even on the mountain, then leave it alone. The pro riders making the most of their bikes are ALL carbed bikes, for a reason. EFI was exciting when they introduced it, but then they quit with their technology.... a simple fixed map and you're stuck..... That is worse than the old school carb! The basic carb you can jet and change minute by minute without a tuner or IFE fuel programmer. Now with the technology of the Smart Carb, you can have the best of both worlds. The velocity and performance of a carb AND better than EFI temp and altitude compensation, and fuel economy.
I am receiving a 42MM CFR Smart Carb for the 450SXF in Feberuary. I will be posting all test results. They are testing now on wheels. Completely blows EFI away in all 3 categories.
As a professional builder and mod tuner, My choices,
#1- Smart Carb
#2- Conventional Carb
#3- The simple EFI open loop system
I am receiving a 42MM CFR Smart Carb for the 450SXF in Feberuary. I will be posting all test results. They are testing now on wheels. Completely blows EFI away in all 3 categories.
As a professional builder and mod tuner, My choices,
#1- Smart Carb
#2- Conventional Carb
#3- The simple EFI open loop system
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Randy I know you and I have discussed this topic at length. Not trying to convince anyone that this is better or worse than that.... Just what I have found. I would love to have a smart carb, but I think the cost is more than most want to spend so I would put the stock carb setup number one. I like the dobeck fi bike because it is a plug and play setup other than welding the bung in your pipe. Last year my stock fi bike dumped a lot of fuel into the oil when the temps dropped below 20-25. There where more than once I had to hand roll my bike over because of I think too much fuel hydro locking the piston against the head when it was about 20. That fuel not only gas washed the lubricating oil off the cylinder, it diluted the oil viscosity. I know a lot of peaple are getting buy running a fi bike with no controller and if it works for them great, just I will not. I was totally green on how this controller worked last year but as I learn I am going to find out just how rich the sx and kx runs as temps drop this year by turning the controller to the read only during the ride. These bikes are running in conditions they where never set up for temp wise, and the dobeck has been working for me.....now I probably hexed my self. Keep your records of what you find on your sx and post here if you would. I would kike to see if you find the same thing I do.....lets go riding...Garry
P
PalousePoo
Well-known member
Garry, does you sons carbed bike ever flood, when it gets tipped over? Making it hard to start.
where we going?
this discussion is right on for 1995 if we were riding sleds: and back then a Lectron offered better performance than any of the efi units. ly
because dirt bikes took the 4 stroke detour the last 15 years no significant FI research advanced dirt bike FI applications. the current FI systems on the market for the 4 stroke dirt bikes are old school and crude by world internal combustion engine standards. Basicly in a very limited market we have low grade cast off junk and no technology. Kudos to the guys that have come up with band aids.
Good point was made by rush 44 that in the sno bike group more riders are likely capable of programing FI than changing brass in a carb. And that's the direction this is going. Foolish to have a system putting gas in the oil ?? how bad is that. Will be fixed when demand is there.
The 2 stroke bike guys are in the no technology void. Great FI on the 2 stroke sleds/outboards and advancing daily. Nothing on the bikes. We're riding and buying motors unchanged for 15 years......poof nada. My new sno bike has an engine I was excited to buy in 1998. I am looking at spending 8k in the spring for a new trail bike with a motor that hasn't changed except for carb brass since 1998 ??
FI complicated and unreliable, apparently on the bikes. REST of the world, only option and bullet proof. Bikes will be there, just no today.
It will be interesting to revisit the new smart carb issue a couple of years down the road. Still an organized leak with new tweaks. Its sucking vs blowing, and in the larger world of engine management blowing is winning big time........in every venue.
Just a matter of time on the bikes.
this discussion is right on for 1995 if we were riding sleds: and back then a Lectron offered better performance than any of the efi units. ly
because dirt bikes took the 4 stroke detour the last 15 years no significant FI research advanced dirt bike FI applications. the current FI systems on the market for the 4 stroke dirt bikes are old school and crude by world internal combustion engine standards. Basicly in a very limited market we have low grade cast off junk and no technology. Kudos to the guys that have come up with band aids.
Good point was made by rush 44 that in the sno bike group more riders are likely capable of programing FI than changing brass in a carb. And that's the direction this is going. Foolish to have a system putting gas in the oil ?? how bad is that. Will be fixed when demand is there.
The 2 stroke bike guys are in the no technology void. Great FI on the 2 stroke sleds/outboards and advancing daily. Nothing on the bikes. We're riding and buying motors unchanged for 15 years......poof nada. My new sno bike has an engine I was excited to buy in 1998. I am looking at spending 8k in the spring for a new trail bike with a motor that hasn't changed except for carb brass since 1998 ??
FI complicated and unreliable, apparently on the bikes. REST of the world, only option and bullet proof. Bikes will be there, just no today.
It will be interesting to revisit the new smart carb issue a couple of years down the road. Still an organized leak with new tweaks. Its sucking vs blowing, and in the larger world of engine management blowing is winning big time........in every venue.
Just a matter of time on the bikes.
I was all over the FI thing when it first arrived and really wanted to move up. In retrospect now that my bike is doing dual duty summer and winter I'm happy with the carb. Jetting a carb is a piece of cake, there's no voodoo. I dumped my bike the last few days riding a couple of times, stand it up, push the button and go again. I'll take a long hard look at the 4 stroke Smartty when it shows up but more for the performance improvements rather than the jetting issue. Once you are jetted for your altitude with a carb you are set.
Now you'd have a much tougher time convincing me to ditch my E start, LOL
M5
Now you'd have a much tougher time convincing me to ditch my E start, LOL
M5
All very good and valid points there and yes you are right. When we start seeing good advances in electronic fuel management on our bikes I will be rite there taking advantage of it. But as of rite now I am fine with a crude organized leak. It runs great for me now. Don't get me wrong, I would love to have my kit on my 13 kx450 in my garage, that thing is way more manageable on a track than my 07, 08 were. That being said my 07 and 08 were harder to ride out of a corner or in mud cuz they have waaayyy more bottom end power then the fi bikes I have had, which is bad for track but very good for snow! But for now ...nope.
And for the flooding when tipped over, I haven't had an issue with it, just pull the hot start and couple kicks your back in action.
And for the flooding when tipped over, I haven't had an issue with it, just pull the hot start and couple kicks your back in action.
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Following
. Im on the list to be called when they are ready. In the market for a well built ,user friendly ,plug and play fuel controller for a 2013 ktm 500 and suggestions .
