Lead Acid or Lithium Snow bike Battery?

Nov 14, 2017
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Cory, the PR2 on my FX/Yamaha made it extremely difficult to start cold. Started no problem warm. With my stock ECU my bike started cold no problem. Can you try your stock ECU and see if there’s any difference? Just a thought. Hope you get it figured out.
Further confirmation that it is likely the PR2. NeedPowder, did you ever find a way to make it start better with the PR2 in?

FYI: I just emailed Jeff at PR2 directing him to this thread and asking if he has any advice. I will let you know what the response is.
 
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needpowder

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Further confirmation that it is likely the PR2. NeedPowder, did you ever find a way to make it start better with the PR2 in?

FYI: I just emailed Jeff at PR2 directing him to this thread and asking if he has any advice. I will let you know what the response is.
Hopefully jeff has some advice if that is in fact part of the issue. My FX had a kick starter. What I found was if I slowly cycled the kicker 6 to 8 times it would help but still had to crank it quite a bit. I tried turning up the low to 6 but didn’t see much difference. I think it’s a fuel issue and kind of “priming”with the kicker helped. All bikes are a bit different though. I just went back to my stock CDI. Problem solved. Change the oil more often. Whatever.
I have that same PR2 on my 17 YZ 450 F with no electric start. Works awesome. Haven’t started it yet in less than 20° but only takes about half a dozen kicks.
 
Nov 14, 2017
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Hopefully jeff has some advice if that is in fact part of the issue. My FX had a kick starter. What I found was if I slowly cycled the kicker 6 to 8 times it would help but still had to crank it quite a bit. I tried turning up the low to 6 but didn’t see much difference. I think it’s a fuel issue and kind of “priming”with the kicker helped. All bikes are a bit different though. I just went back to my stock CDI. Problem solved. Change the oil more often. Whatever.
I have that same PR2 on my 17 YZ 450 F with no electric start. Works awesome. Haven’t started it yet in less than 20° but only takes about half a dozen kicks.
My guess is that its no spark, since cranking the throttle doesnt seem to make a difference. Although I am not sure if that still shoots fuel into the cylinder like it used it. Before FI, if you turned the throttle on a 4stroke it shot fuel into the cylinder.
 
Mar 9, 2017
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Cory, the PR2 on my FX/Yamaha made it extremely difficult to start cold. Started no problem warm. With my stock ECU my bike started cold no problem. Can you try your stock ECU and see if there’s any difference? Just a thought. Hope you get it figured out.
yup I will try that. the pr2 is fairly new though, and ive always had starting problems even at the start (those were -30 days though with the stock ecm) so I will throw the stocker in and see how it does at -2C.

not sure if this is relevant... but my bike doesnt like starting with the choke ON/OUT lately. it seems to fire up when the button is pressed in and the choke is effectively off though.. weird.
 
Mar 9, 2017
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My guess is that its no spark, since cranking the throttle doesnt seem to make a difference. Although I am not sure if that still shoots fuel into the cylinder like it used it. Before FI, if you turned the throttle on a 4stroke it shot fuel into the cylinder.
I read that it wont... ive been googling "ktm wont start" for weeks now and have read every thread on TT, ktm talk, and here. I read that theres no accelerator pump like the carbed bikes have so opening the throttle wide open on a FI bike, or cracking the throttle real quick, doesnt do anything.


ive also read that a higher RPM setting (turning that red knob above the clutch where the kickstart is) could increase fuel at low RPM/idle and possibly help starting. my idle is already around 1700-1800 ish though.
 
Mar 9, 2017
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here is starting with the stock ECM. did WAY better:

one thing id like to note that I think is VERY important is that with the stock ECM, and choke off (I tried to film it), the idle was like 2400RPM as seen in the video. I needed to turn the idle screw out nearly 1.5 turns to get the idle back down to 1800ish.

I wonder if I put the pr2 on if the idle would be so low it wouldnt even start...


 
Nov 14, 2017
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I read that it wont... ive been googling "ktm wont start" for weeks now and have read every thread on TT, ktm talk, and here. I read that theres no accelerator pump like the carbed bikes have so opening the throttle wide open on a FI bike, or cracking the throttle real quick, doesnt do anything.


ive also read that a higher RPM setting (turning that red knob above the clutch where the kickstart is) could increase fuel at low RPM/idle and possibly help starting. my idle is already around 1700-1800 ish though.

Cory have you done the PR2 "set up" procedure with your bike? Where you hit the starter for 10 seconds with the kill switch depressed without touching the throttle or something like that?
 
Mar 9, 2017
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Cory have you done the PR2 "set up" procedure with your bike? Where you hit the starter for 10 seconds with the kill switch depressed without touching the throttle or something like that?
nope, never heard of it until now and I emailed jeff a bunch last year regarding my problems. wonder why he wouldnt mention it?

edit: emailed Jeff about the PR2 "set up" procedure , also emailed him this morning about the starting issue that I see you did too... hes gonna have a lot of emails from us haha.
 
Nov 14, 2017
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Ok, here is a video of me starting the bike. It just came out of a warm shop, so if it was my other bikes it would take about 1-2 seconds of cranking to fire up. You can see the results for yourself LOL


Jeff just emailed be back and suggested the TPS setup procedure. I have done it before, but I am going to do it again. Cory, maybe try this and see if it helps:


KTM Models (all models with adjustable idle): Mark idle adjustment knob (Red on top of throttle body) with sharpie marker and rotate the screw counter-clockwise four (4) turns (lower idle).

Depress kill switch and kick over the engine or press the start button on electric start models and be certain to leave the throttle closed. Kick engine twice or press starter for two seconds. Stop kicking and keep kill switch depressed. This zero’s the closed throttle TPS value.

Next, wait two to five seconds with kill switch depressed.

Release Kill switch

Finally, open throttle completely, depress kill switch and kick over the engine or press the start button on electric start models while maintaining fully open throttle. Kick engine twice or press starter for two seconds. Stop kicking and keep kill switch depressed. This zero’s the full (100%) throttle TPS value.

Wait 2 to 5 seconds. Your TPS values are now stored in the Vortex ECU.

Release Kill switch

KTM Models: Return idle to original position -four (4) turns clock-wise

Start motorcycle/ATV.
 
Mar 9, 2017
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my directions were a tad shorter than that but same thing he emailed me "Plug and play....sometimes you may need to sych the TPS to ECU....this is done really easily. No throttle, depress kill, stab starter....release all. Now do same holding throttle fully open. Release all. Done. The ECU has just leaned the 0% and 100% throttle positions. "

I will try that in the next few days.. my kill switch seems to only work 50% of the time so when the new one shows up I will do that procedure.

interesting how your voltage stayed around 13.2 also. hmmm.

id like to try starting now with the stock ecm at -15 or so.
 
Nov 14, 2017
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The directions I had when I first installed this were similar to what you have above. I didnt know about backing off my idle screw I dont think. I am going to try that and pray it helps.
 
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GKR

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My directions were similar to yours before. I didnt know about backing off my idle screw I dont think. I am going to try that and pray it helps.
That will definitely make a difference because if you don't back off the idle and do the calibration it sets the "0 throttle" position at your idle position which is not technically zero throttle. If you do it correctly then "0 throttle " is truly that and at actual idle the PR2 will expect to add fuel because it now calculates that your throttle body is partially open giving the motor air so it adds fuel to acheive a proper idle mixture. Currently the PR2 will assume that your throttle position is fully closed when you try and start so it may add little to no fuel which may be why you are having such starting trouble. Does that make sense?
 
Nov 14, 2017
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That will definitely make a difference because if you don't back off the idle and do the calibration it sets the "0 throttle" position at your idle position which is not technically zero throttle. If you do it correctly then "0 throttle " is truly that and at actual idle the PR2 will expect to add fuel because it now calculates that your throttle body is partially open giving the motor air so it adds fuel to acheive a proper idle mixture. Currently the PR2 will assume that your throttle position is fully closed when you try and start so it may add little to no fuel which may be why you are having such starting trouble. Does that make sense?
That makes a lot of sense, absolutely. I want to let the bike sit overnight before I try to start it. I am hoping this is the fix I needed!
 

needpowder

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here is starting with the stock ECM. did WAY better:

one thing id like to note that I think is VERY important is that with the stock ECM, and choke off (I tried to film it), the idle was like 2400RPM as seen in the video. I needed to turn the idle screw out nearly 1.5 turns to get the idle back down to 1800ish.

I wonder if I put the pr2 on if the idle would be so low it wouldnt even start...


Nice!
 
Nov 14, 2017
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I started the bike again tonight instantly with the stock ECM.

threw on the pr2, would NOT start.

put the stock ecm back on, fired right up.

Im stoked to try that TPS reset.
Well, I guess we have identified the problem! Hopefully that TPS reset fixes it. I did the reset yesterday, and I will try the start today. Fingers crossed. If it doesnt work I don't know what I will do.... Hopefully Jeff is willing to do something....
 
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