690R carburetor conversion mod.

Discussion in 'Thumpers' started by Visigothic, Feb 27, 2011.

  1. Visigothic

    Visigothic Been here awhile

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    Thought this needed it's own thread too. Good idea dr664




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    dr644<SCRIPT type=text/javascript> vbmenu_register("postmenu_9822759", true); </SCRIPT>
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    Originally Posted by dr644 [​IMG]

    Anyone interested in starting a new thread to discuss about converting the 690 FI to Keihin FCR carb?
    I know there are many reasons to keep the FI running, and I believe things will be solved in the near future. However there are some good reasons also to start a discussion on how to install and what parts are required to convert the current FI into carburetor.


    Pros and cons of FI:
    • Pros:
    1. handle any change in fuel and location
    2. no need for choking the bike when cold
    • Cons:
    1. not a lot of expertise in FI as much as in carb
    2. issues can only be solved by the dealer and we never know exactly what they are doing
    3. there are some reported problems with the 690 FI that are making people scared about this outstanding bike
    Pros and cons of carb:
    • Pros:
    1. The competition bikes for the Dakar and Baja still use Keikin FCR carbs
    2. reasonably easier to fix - and we can do it - at least we know a lot more
    3. can be tuned to our taste :evil
    4. cheaper to maintain
    • Cons:
    1. sensitive to changes in fuel, temperature, elevation, etc.
    2. will require some investment $$ :eek1
    Would you be interested in a new thread about this conversion?



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    Visigothic<SCRIPT type=text/javascript> vbmenu_register("postmenu_15295896", true); </SCRIPT>
    Gnarly Adventurer

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    That would be sweet. I don't trust EFI for the same reasons you stated above. Its bad enough to find a dealer that will do quality work but the way things are going finding a KTM street dealer or any KTM dealer in general near me is now a 2-4 hour drive one way for service to have the the thing re-flashed because of driving under some over powered high line or etc. I keep looking at the 530exc over the 690 for simplicity sake. It would be a nice option for an aftermarket-er to develop but I don't see it happening. Too few 690s out there with fewer on the horizon due to the economy and KTM's market plan to produce fewer per year to balance the market demand vs. cost and in forcing dealers to handle models that dont sell well in their demographic and economic areas. i.e. "Street dealer" or "dirt dealer". no buffet plan. I personaly thought putting the 690R or 950SE as a street only dealer item was really missing the mark I think ,but what do I know. Street bikes are in major cities and suburbs. Dirt bikes are more suburb and country. Yes you can find all the 690s you want in down town LA, Detroit, Dallas, Chicago etc. but few at John Doe's "Flirt with dirt MX shop" surrounded with miles of back woods riding close to home. Unless due to cost concerns only the average city slicker can afford a $10K+ dirt bike but at the rate their going all their bikes will be $10K+ soon. :tough

    ANYWAY; If someone made a carb. mod I might think even more about 690, I think it's a super idea.





    Seth S<SCRIPT type=text/javascript> vbmenu_register("postmenu_15295488", true); </SCRIPT>
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    I'll simply say that most people don't trust fuel injection simply because they don't know how it works. This is a not a judgment on you. Carbs have been around for years and they tend to be reasonably reliable. They have the additional advantage of requiring fewer electrical components to run. On the down side they are less efficient and more difficult to tune.

    For a carb conversion I'd look at what they use on the 690RR. According to the fische for a 2007 690 RR the bike uses: CARBURETOR FCR-MX4100BTPS 07 KTM part number: 76231001000 which can be ordered through Munn Racing for $725 + shipping....can't comment on availability but you may be able to cross reference those numbers for a better deal. Also keep in mind you will need to swap over to a different ignition system as the Stock bikes the efi and ignition are integral to one another.

    So my personal feeling is that I would rather stick with the fuel injection. However, the stock 690 fuel injection does suck. I can ride the bike but after riding the newer Husabergs which just have spot on efi you realize how much better the 690 could be. And I think the way to go for a better EFI system is to either adapt the Berg system or install a Microsquirt setup.

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    Visigothic<SCRIPT type=text/javascript> vbmenu_register("postmenu_15295896", true); </SCRIPT>
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    Here is the 690rr ignition from Munn, could it be this simple along with the carb ????? There's got to be more to it.

    [​IMG]





    Ryman<SCRIPT type=text/javascript> vbmenu_register("postmenu_15296005", true); </SCRIPT>
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    <TABLE border=0 cellSpacing=0 cellPadding=4 width="100%"><TBODY><TR><TD style="BORDER-BOTTOM: 1px inset; BORDER-LEFT: 1px inset; BORDER-TOP: 1px inset; BORDER-RIGHT: 1px inset" class=alt2>Originally Posted by visigothic [​IMG]
    here is the 690rr ignition from munn, could it be this simple along with the carb ????? There's got to be more to it.

    [​IMG]

    </TD></TR></TBODY></TABLE>I think you also need the cdi <!-- / message --><!-- sig -->
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  2. Visigothic

    Visigothic Been here awhile

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    I have dug pretty deep int the carb swap thing
    problem is the head on the rr is diffferent than on ours, you will need to make a adaptor to attach the carb to the head and then figure out the filter( not hard)
    a cdi from a rfs will work on the ignition
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    #2
  3. mousitsas

    mousitsas Long timer

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    what would the problem be if you leave the stock ECU plugged-in, while the only difference is that the throttle body is replaced with a carb? It is even possible to fool the ECU that the injector is in place with an appropriate resistor. I can't see any reason why wouldn't that work fine.
    #3
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  4. Visigothic

    Visigothic Been here awhile

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    I'm no expert not even a mechanic but it might be that the CDI/ECU is tied into the FI to automaticly talk back and forth to each other to get the best milage/emissions results advancing the spark or retarding it based on temp, air pressure,etc. Of course this means also that the amount of fuel is also regulated at the same time based on said data. This is done multiple times a second and recalculated at an instant...........I'm just guessing. With no FI data input it might not work but your idea of fooling it with a constant rate data stream (resistor) could do the trick, maybe not. Im not sure if the CDI/ECU is programed to see a constant FI data stream or non-coded stream as a malfunction and shut down due to emissions programming in the CDI/ECU if there is any. Hence new CDI/ECU. Someone has had to have tried it, they're just not talking. :jjen. ouch!
    #4
  5. DirtJack

    DirtJack Adventurer Supporter

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  6. Visigothic

    Visigothic Been here awhile

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    Thanks bro, its a good read. I now know more than I needed to.:huh It seems I was kinda close on my assumptions, but only close.:lol3

    Call me an old timer but I like carbs even more now after seeing how this thing works.:eek1 In other words "If you don't have a mythical KTM street dealer nearby with a XC-1 your screwed." I say this from my personal view point in that the nearest "street dealer" is 4 hours 2 states away in one direction and 6 hours one state away in the other. Its why I keep swinging between a 530 or kicking the habit off orange all together and go XR650L. I doubt an indipendent shop is going to be able to help someone with a 690 in a pinch.:cry

    Im not sure if there is an independent vendor who provides mapping data via power commander or what ever they use to tune EFI for a KTM. I could use some learning here.:ear

    [​IMG] Something VooDoo....what?.....Anyone....?......Anyone at all ?
    #6
  7. Mudguts

    Mudguts when in doubt GAS IT

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    you seem to be blaming the FI when its the fuel pump that gives the most trouble even if you use a carb you still need a fuel pump cause fuel does not flow up hill my friend

    I'm using the Vortex ECU and love it




    Vortex ecu .





    Note: ECU-4 picture shown - this is used on several models
    We have completed testing the KTM690R Enduro with the VORTEX X10 ECU with some excellant results using the both the Akropovic and FMF (quiet Insert) pipes. The standard Engine Management System uses a throttle by wire system that severely effects the throttle reponse and throttle range (does not open to full throttle).The Vortex X10 ECU replaces both the standard ECU and the Throttle control box and therefore allow the rider to get instant power when commanded by the throttle rather than the lag experienced with the standard system. In order to achieve this a simple adjustment of the idle speed control stop is required. Other than that just plug in the Vortex X10 ECU and go. We have developed Ignition and Fuel Maps that provide a range of power settings to suit road and high speed racing to traction settings to smooth out the power delivery for trail use. In addition we will add some maps for fuel economy so if you are low on fuel you can increase your range. The optional handlebar switch is also available to switch between 2 maps on the fly.
    Main Features
    [FONT=Trebuchet MS, Arial, Helvetica]- Get Real Throttle Response[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Improved Low to Mid Range Power and Throttle Response[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Enduro maps soften the low throttle for more control[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Economy maps for longer fuel range[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Improved Top End Over Rev Power[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Customise your power delivery to suit the track conditions or your riding style.[/FONT]
    [FONT=Trebuchet MS, Arial, Helvetica]- Diagnostic Fault Codes - Flashes codes on the standard FI light in the event of a sensor failure. [/FONT]​
    #7
  8. LukasM

    LukasM Long timer

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    I can sort of see where you are coming from but how many people do you know that have had problems with a Mikuni vacuum pump? Doesn't get much simpler than that, with low pressure you can even use clear tubing to see if the fuel flows or not. And if it does fail for some strange reason replacements are $50 (rebuild kits $15) vs. $350 or so for the FI pump.
    #8
  9. Mudguts

    Mudguts when in doubt GAS IT

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    I had even though of going carb but figured out it was just easyer to go the vortex , it even has a soft first 1/4 throttle setting for those that don't like the snatch of FI , it works quite well

    even with a carb vac pump or electric its still some thing that can go wrong.
    shit you could be stuck by lightening after being bombed by a scud missile and attackted by a drop bear !!!!!!

    like some seid on another post stop stressing about what could go wrong and ride the the bloody thing . its all apart of the adventure


    i swaped bikes with Brute last week athe wanted mine back ASAP . I forgot how bad the standard ECU is and the butterfly servo makes the throttle so heavy
    #9
  10. MookieBlaylock

    MookieBlaylock Long timer

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    If i lived far from a dealer i would not have an fi bike without a means of tuning it and correcting faults. That being said the fi on the 690 is jerky even when tuned to perfection. Vortex or tuneboy
    #10
  11. Dazed Productions

    Dazed Productions Been here awhile

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    I am going back a way here, but the an advantage of carbs compared to FI always used to be weight as well. For FI you need a large fuel pump (if you need one at all for carbs its small) and all the throttle bodies and electronics are heavier. At that time some of the GP bikes started moving to FI and the only reason was that with FI they could combine the systems with traction control etc. Just as engine management, flatsides were still better (this was around the time they let the 4-strokes compete with the 500s and I was discussing with some of the FI manufacturers)
    #11
  12. Dazed Productions

    Dazed Productions Been here awhile

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    Daft question here (I ride an RFS not an LC), why can't you use the ECU and carb off a 640?
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  13. LukasM

    LukasM Long timer

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    The carb is a sucky BST40 (unless you get the FCR from a 625/660 which would be good). I doubt the stator will interchange (new LC4 is completely different engine from 640). The ignition box might work although it will be far from ideal due to the different engine characteristics.

    I'd get a used 41mm FCR with TPS and the 690RR ignition system.
    #13
  14. Dazed Productions

    Dazed Productions Been here awhile

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    Is the 625/660 a 41mm FCR then?
    Ebay is a great source of such things so I imagine that one could be sourced simply.

    Someone said on here that the ignition from the RFS works, but there are also aftermarket ignition systems available (aimed at old bikes/customs) that could probably be used.

    I can't see that you need to change the stator unless the new one doesn't have a timing coil and the ignition system you choose needs one (as the RFS one does). I am sure aftermarket ones would work with an FI pickup. The main worry about going aftermarket is ensuring that its reliable IMO. On balance, the 690RR does sound like the ignition system, as long as it works with the stock stator, or if you change to the RR stator, that the RR provides all the electrical power you need.
    #14
  15. THOR450

    THOR450 n00b

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    mudguts, I am very interested in the route you have taken here with the Vortex. Do you know anyone else here that has the Vortex? I am frustrated with the bike and the lack of FI fixes, despite all of the people working on them on several websites.

    What was the price of the Vortex and did you have any set-up costs? Did you do the simple idle adjustment? Sell me on this thing!!!! Thanks
    #15
  16. BikePilot

    BikePilot Long timer

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    Well done FI usually saves weight as compared to carbs, this was highly touted years ago when most all other internal combustion vehicles switched to FI :lol3

    So far I've found FI to be far less troublesome than carbs, not to mention more consistent performance. I don't doubt that some FI systems are poorly implemented and unreliable, but its not endemic to the nature of FI, but just a case of crap build quality/engineering. All that said, for really remote back country touring a gravity-fed carb is pretty hard to beat as whatever does go wrong can probably be fixed simply.
    #16
  17. LukasM

    LukasM Long timer

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    Yeah, 625/660 use a 41mm carb. It is the one referred to as generation 2, and has a removable intake bell. From what I see on the microfiche the 690RR appears to use the gen 3 which has a fixed bell and is a bit shorter. The 07+ SX-F is a good source for used gen 3s with TPS.

    To make the carb fit I see two options:

    1: You could simply try the 690RR rubber boots on head to carb and airbox to carb and see how they fit and line up. If the airbox outlet and the head inlet are in the same location and have the same size, a gen 3 carb should slot right in. Small adjustments in length could be made by using a gen 2 carb, and if necessary getting a custom intake bell that will bolt on (Noss Machine or Dirt tricks are good sources).

    2: If the 690 throttle body is longer or the same length, you could put some turned adapter rings on carb inlet and outlet to make up for the different diameters and length. Then you could keep existing rubber boots and the airbox in place.


    I have a 690 TB, and both gen 2 and 3 FCRs in my garage so maybe I can help out by posting some comparison pictures and measurements.
    #17
  18. bobzilla

    bobzilla Dirty Old Man

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    you tha man Lucas :clap
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  19. Mudguts

    Mudguts when in doubt GAS IT

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    The vortex is aplug and play system it shut off the secondary butterfly and servo so you can get full throttle makes the the throttle nice and light like a carb 10 differnt maps and on the fly map change so no stoping the engine to change maps you can get the software to make your own maps (it is very technical) it is not a add on it totaly replaces the stock ststem I
    #19
  20. Dazed Productions

    Dazed Productions Been here awhile

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    You need to check your sources as when applied to bikes this statement is just plain wrong.
    My sources are Sagem, the firm that used to make the FI for Triumphs. I went for a job interview there many moons ago (which I got offered but turned down) and discussed systems at length.
    I will admit that since then the FI systems have doubtlessly got lighter and narrowed the margin on carbs, they may even now be lighter but it was never a plus point in the bike world back then. Cars, I can believe it as in a car it is rare to have multiple throttle bodies. They would swap from what would have been a multi-carb setup to a single FI throttle body. This is not the case in bikes.
    It is no secret that the prime driving force has been emissions in the bike world. FI is needed for catalytic converters and to meet all the new guidelines.

    To give you two examples. Take a small single cylinder bike, in the carb world there is no fuel pump. The carb consists of a metal throttle body with a float beneath, some jets and a spring loaded slide. Add to that an EFI box, a crank coil or pickup, spark plug, some power and your done.
    To do the same in FI you need to have a high pressure fuel pump. This needs to have a fuel regulator, you still need the throttle body. You need higher powered generator and battery to power the pump and FI system and to allow it to start (as yet, no-one has made a kickstart FI bike with no battery that I know of!). Then you need the injector, the standard crank pickup but also a cam pickup. I cant see how you can be adding and loosing weight?

    On a big sports bike, a traditional bike has a bank of 4 carbs and a low pressure fuel pump. An FI one still retains the 4 throttle bodies and even have secondary valves to control air flow to mimic the CV operation. The fuel pump gets a lot bigger on the FI bike, around 2000 all the FI bikes lost about 1 litre of fuel capacity to house the pump in the tank. The throttle bodies are narrower on FI though, I can imagine that on a bike like this the difference is pretty minimal now.
    #20