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Discussion Starter #1
I recently completed the build of my 08. I installed a STD bore wiesco 12.4 piston, Stage 2 hotcams , a FCI with a box and full yoshi exhaust. I had planned on buying a PIM 2 but I recently traded for an 09 with a cracked case that had a LEXX 3 button programmer on it so I just pulled that off and put it on my bike. I searched the forms and set up my fuel controller as; Green:4 , Yellow:4, Red:2 , Green/Blue :7 , Yellow/blue:3 , Red/Blue:5. The bike was running fair on these settings but seemed a little lean sitting in the shop idling so i bumped the green to 4.5. I rode around the yard not exceeding half throttle because I'm still breaking engine in. The bike died on me and was really tough to refire and wouldnt start until I gave it a shot of starting fluid. The bike will start up and idle well when cold but when it heats up and you free rev it and falls back down to a high idle. I have not checked the plug to see how it's burning yet, I'm just curious as to what everyones opinion is. It runs FAIR with the settings listed but I'm really worried about it not wanting to refire if you stall it out. Also when i just went out and tried to fire it to check my programmer settings it wouldn't fire up at all and it was warm i tried starting fluid still nothing the low fuel light came on so i shut the key off and went back inside and came out again a half hour later NO FUEL WAS added to the tank. I turned the key on no low fuel light came on and it fired right up.

Side notes
-Only fuel i put in this is 93 octane
-I live in southern illinois (if altitude matters in this situation)
- should i just buy a PIM-2 and start over
-This is not my first rebuild i've ridden for years and rebuilt many of my own and others trx's and 400ex's.
 

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Well crap... I wish I could offer more help than this, but I really can't.

With a stock ECU, stock compression, KX Cams, FCI, adjustable exhaust, I left the set points where each mode "comes on" in the normal position they were set by EHS Racing.

I ended up with my low-mid-high fuel level set at 4-8-8.

Mine ran fine like this. But it does not start up worth a CRAP like this. If you watch the controller in action during cranking... if it would stay running long enough for it to do it's Knight Rider scan thing it would stay alive and start to idle better.

However, it would run OK on 4-8-8 but did the same thing. It would want to idle different RPM's as if it were lean. But adding a half more fuel was worse and taking away a half less fuel was worse.

I could start to let out on the clutch just enough to slow the idle, then snatch it back in and the idle would never recover back up. I could barely barely touch or tap the throttle lever and it would jump back up. You know just enough of a tap to move the TPS like 0.01v was enough.

No amount of adjusting the controller or the idle knob nor any combo of the two helped any at all. And heck I have a highly adjustable exhaust system too and tried tinkering with that as well in combination to no avail.


I just assumed in my case it is because my motor is "degreed" a little different than stock and it just ain't never going to work on mine until returned to stock.


But maybe this is par for the course with a 3 button after some mods? Maybe the controller just takes a bit to scan and set after starting? And it needs fuel it doesn't get until then? And I dunno about the weird idle stuff.
 

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Discussion Starter #3 (Edited)
I understand that in order to correctly tune my 450 would be to get a pim2,pro-com or one of the powercommander variety's, but I'm not a competitive racer just a weekened warrior so I'm in for the most bank for my buck. I don't really have any atv dyno's close by, and I hate to spend 600 bucks on a pim and data box or a PCV and an auto tune. I just want my machine to run correctly and make safe power. I also set my idle at 16 or 17 clicks wasn't a night and day difference but seemed to run better with that
 

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procom and TB juice box pro are both right around 200 bucks.

and there is a few members on here that can most likely tune one of those two to make your quad run better.
 

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I have the lexx i think i got it close but who knows the right way is to have it dynoed but i dont even know any local places
 

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Discussion Starter #6
procom and TB juice box pro are both right around 200 bucks.

and there is a few members on here that can most likely tune one of those two to make your quad run better.
I'm considering the juice box I like the idea of a full standalone ECU like the procom but I have heard mixed reviews on the procom. Also i'm worried about being able to find a map for both the juicebox and the Procom. I don't know that I will want to adjust timing advance because I don't want to have spark nock. Thats why i was just trying to get by with this lexx controller

Thanks for the comments keep them coming this is all helping out!
 

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Just curious when you said: it hard to restart, did you double check the valve clearance...?

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)

If it running a high Idle could be a lean mixture or a loose throttle body clamp...

Try the 4-8-8 settings Duster recommended...or boost the fuel until the motor becomes lazy, then back it off 1 point, when revving at low 3500 RPMs, repeat at 6000 RPMs & 8500 RPMs to adjust your controller...

and double check the TPS yellow wire & Lexx controller wire tap to see if it's bad.frayed or ok!....

Does the low fuel light still come on...??
 

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i think the lexx just plugs into the injector circuit. i don't think it has a tps connection.

i ran a hmf optimizer(they are all rebranded controllers) with big three on 4.5-6-5.5 at sea level and it ran good.

but since you have cams you might need to bump the middle numbers up more like duster said.

maybe 4.5, 7-8 6-8. somewhere in there
 

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Discussion Starter #9
Just curious when you said: it hard to restart, did you double check the valve clearance...?

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)

If it running a high Idle could be a lean mixture or a loose throttle body clamp...

Try the 4-8-8 settings Duster recommended...or boost the fuel until the motor becomes lazy, then back it off 1 point, when revving at low 3500 RPMs, repeat at 6000 RPMs & 8500 RPMs to adjust your controller...

and double check the TPS yellow wire & Lexx controller wire tap to see if it's bad.frayed or ok!....

Does the low fuel light still come on...??
I haven't been back to the shop yet but i will let you guys know what I come up with. Valve lash is spot on ,when it didn't want to start it acted like it was almost flooded and after it refired from that i rode it shut it off and it fried back up so that rules that out. All clamps are tight and I checked for a vacuum leak by spraying stating fluid around all clamps in front of TB that also checked out. I guess Later this week i will try the setting that you guys recommended. Just to double check You're saying to set my GREEN:4 YELLOW:8 RED:8 and leave my Green/Blue at 7 yellow blue at 3 and red blue at 5
 

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Just curious when you said: it hard to restart, did you double check the valve clearance...?

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)

If it running a high Idle could be a lean mixture or a loose throttle body clamp...

Try the 4-8-8 settings Duster recommended...or boost the fuel until the motor becomes lazy, then back it off 1 point, when revving at low 3500 RPMs, repeat at 6000 RPMs & 8500 RPMs to adjust your controller...

and double check the TPS yellow wire & Lexx controller wire tap to see if it's bad.frayed or ok!....

Does the low fuel light still come on...??
I haven't been back to the shop yet but i will let you guys know what I come up with. Valve lash is spot on ,when it didn't want to start it acted like it was almost flooded and after it refired from that i rode it shut it off and it fried back up so that rules that out. All clamps are tight and I checked for a vacuum leak by spraying stating fluid around all clamps in front of TB that also checked out. I guess Later this week i will try the setting that you guys recommended. Just to double check You're saying to set my GREEN:4 YELLOW:8 RED:8 and leave my Green/Blue at 7 yellow blue at 3 and red blue at 5
Here's the lexx KFX450 base setting I found in a search...to help explain...

08-06-2011, 02:56 PM
NHRider

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Join Date: Sep 2010
Posts: 111
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I have mine set a little above the OPEN setting that comes with the instructions. Like I said it seems to run fine and I thought it started up fine but now that you say it I have had a couple instances on the trail where it takes a while to start back up again.

These are the base settings
KFX450 Base Settings


led
what it does
quiet core
open
green
cruise/light acceleration
2.5
5
yellow
mid load/med acceleration
2.5
4.5
red
full throttle
2.5
2.5
green-blue
green fuel lower switch(on)-0 is early, 8 is late
8
8
yellow-blue
yellow lower switch(on)-0 is early, 8 is late
3
2
red-blue
red lower switch(on)-0 is early, 8 is late
3
3


quiet core (as delivered): airbox lid on, LEXX MX-e exhaust with quiet core

open: airbox lid off, LEXX MX-e exhaust with 46mm race tip



__________________________________________

When you get the FCI installed...

Start with your setting first and see how far off it is...if it cut's out & stalls your too lean then go with Duster's green 4-yellow 8- blue 8 if the motor is lazy to accelerate drop down to 4-7-7 & see...

& start around the green-blue 6 yellow-blue 4 & red-blue 5 setting...again if the motor is lazy when accelerating drop it a point & see...!
 
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