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FI Bikes, Over-fueling, and Thermostats

Good temps

Got some testing in with the engines shrouded with some plastic to keep snow off cases I was able to maintain an average of 155 degrees according to the voyager temp reading. U can watch the temps rise and fall between 145 and 180 all day as the thermostat opens and closes. Did a oil change today and looks like new still. Looks like this is the real answer to all your overfueling issues on the Fi bikes.
 
just because the bike is running at temp and can burn the fuel out of the oil doesnt mean its not pig rich.

big single 4 strokes can gobble up fuel without missing a beat where others would be missfiring. I have personally watched the pulse width of a stock injector from startup (25*F) to ready to boil over and the bike and there is a negligable change, On the kawi and the hondas it seems that the coolant temp is NOT what most of the mapping is based off of. so yes, your oil stays nicer if its warm, but that doesnt mean its still not puking fuel into the bike.
 
point is to get running good as stock bike in summer

just because the bike is running at temp and can burn the fuel out of the oil doesnt mean its not pig rich.

big single 4 strokes can gobble up fuel without missing a beat where others would be missfiring. I have personally watched the pulse width of a stock injector from startup (25*F) to ready to boil over and the bike and there is a negligable change, On the kawi and the hondas it seems that the coolant temp is NOT what most of the mapping is based off of. so yes, your oil stays nicer if its warm, but that doesnt mean its still not puking fuel into the bike.

Im not trying to go after more power right now just keep oil clean and bike running like its on dirt. Im sure a fuel controller can give us all more power but just to have it running clean and reliable is my goal right now.
 
Im not trying to go after more power right now just keep oil clean and bike running like its on dirt. Im sure a fuel controller can give us all more power but just to have it running clean and reliable is my goal right now.

One thing to note was that even when I had my thermostat in but no fuel controller I was still adding fuel to the oil. It wasn't near as much as when I didn't have a thermostat, but nonetheless fuel was added. I think what I like most about the fuel controller so far is just how well it cleans up the bike... not that I necessarily get a big HP boost (in fact I think the HP increase is minimal). Crisp and consistent throttle response, as if I was on dirt in the summer, is what the controller has delivered first and foremost.
 
so this is basicaly a plug and play and tuning takes a little bit of work ?​

Yes it is about as "plug and play" as you can get. The tuning will not really take much work at all since I now know exactly what to do. My problem was I fiddled with some settings, thinking a change would do something that it wouldn't, and ended up retarding my Accel Pump by about 2 seconds and it made for horrid throttle response.

Basically, when you get the controller you will do a few things after initial install. You will first set the desired AFR in Yellow and Red modes. I have set mine to 12.8 in Yellow and 12.5 in Red (12.5 is to be on the safe fatter side, but 13 is the desired AFR). This takes about 10 seconds to do. Next you will want to modify the range of the modes so that Yellow and Red modes are achieved as soon as possible... again about a 10 second process. After that I decided to be on the safe side and richen initial fuel delivery upon entering Yellow/Red modes and fattened my Accel Pump setting. All in all, 30 seconds of programming and you are done.

Outside of the initial programming you will want to adjust Green mode trim for your daily temp changes. Once you know how to do this (and the fact that you make very small % changes to make your AFR right) it's another 10 second daily process.
 
Rush, since we set you up with the controller I edited the code for it so the ranges now come preset right where i put them on yours (and are centered on the 13 mark for appropriate adjustments if people wanted to play with them.) So now all a person would need to do is set the trim in green mode, and set their desired yellow/red.

its hard work :)
 
I have used the dobeck controller on my sleds for a while,and had good luck with them. I may have to try that controller, theres no O2 guage,but Other than my turbo poos I never tuned with 02 before And i was able to get it jetted,200$ seems like a deal? JD's jet kits work good in my 2st KTM's I think I will try it!
 
On a normal dirt application his tuner would have no reason to pull that much fuel, so running out of range would be a very accurate description.

If you wanted im sure the guys at dobeck could reflash it with the same map just slightly larger ranges so you could use it for snowbiking.
 
I have the JD Tuner on my 2012 KTM 500 and it works good for the trails but for Snow Biking it is just OK, I don't feel it has enough range. Blocking off the radiators seem to work best to keep temps up.

When you say range,, you mean the range from 1-6 lights doesnt do enough? Or you want more then green,yellow and red plus the switch points?
 
I know this is a little off toov but what would it take to put an afr gauge on a carbed bike to help dial in jetting?
 
Cwooland, we (dobeck) have a little widget that allows you to run an afr gauge with only a small nutsert in the pipe instead of welding in a large bung, if you have a WR, which i thought you had? we have a power adapter to hook straight to a battery, tender plugin, or a cigarette lighter port.

i jetted my bike on the dyno with this setup and it was rock solid.. and runs good in the hills!
 
When you say range,, you mean the range from 1-6 lights doesnt do enough? Or you want more then green,yellow and red plus the switch points?

The 1-6 range is what I am referring to. However I have blocked off the radiator air fins like 90% and that seems to keep temp up and now the range seems to be OK. I still need to get in some deep powder again to test it under the same conditions but so far I am not making oil ( fuel in oil ) anymore or at least not enough to concern me.
 
I have been conversing with JD the last week, what would you think if we moved the base line from 3 to 4 and made the % pull per # from like 2.5% to like 3% then you could pull 7 X 3% or 21% total ,,,,do you think you need to remove that much fuel? Did you need to add any fuel any where? Aceleretor PUMP? Or any where else! And in the dirt did you add or remove fuel?what altitude have you been riding your 500?
 
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Cwooland, we (dobeck) have a little widget that allows you to run an afr gauge with only a small nutsert in the pipe instead of welding in a large bung!


So how does this install? Buy berg has a verry elaborate exhast that I would hate to butcher up!
 
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think about the problem you have

ok so lets look at the problem we have with snowbikes and what we would normally need to do as far as jetting goes with cold temps and see what makes the most common sence. Im not trying to start a battle with any of the fuel controllers but this is how i look at the problem.

first off i will ask you how your bike runs in 100degree summer heat. I would say your answer will be it rips like a mofo and i never ever have gas in my oil and i dont need a fuel controller to take more fuel out of the system to make it run this way. atleast this has been my experience with my rmz and buds kx450.

so secondly i will ask you if you were jetting a sled for grass drags in the summer 90 degree heat would you add more fuel or less fuel. Now set up the same sled for ice drags at the same location at -20. every jetting chart i have ever seen will indicate that you need more fuel at -20 than at 90 above.
So common sence would say that by no means should we be needing to remove fuel from our bikes to ride in cold weather if they run great in summer heat!

I ask what is the reason our bikes run so rich in the snow! I look at my research so far and can see that the engines are running cold........ our group of 4 bikes 08 rmz450 09 kx450 12 kx450 and 13 sxf450 all have thermostats and trail tech temp gauges installed. few weeks ago with radiators completely taped off and in deep powder they would not read over 100degrees. half way through the day they would hardly idle. you coud just see the black smoke come out the pipe by this time. so much extra fuel and water condesation in oil is going to kill alot of dirtbikes.

in a nutshell Im going to say the first and foremost get your engine temps up alot. these bikes should boil over at between 220-230 and should really run at 200 degrees no problem for best life.
add thermostats, block off radiators and keep the snow off the engine cases any way possible if you dont want your engine it that blown motor thread!!
I have made these plastic shrouds for the kx and think this will be a easy solution to alot of over fueling problems caused by low water temps.
 
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