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112
Joined
8/5/2012
Location
USA
Currently 27hrs on my hour meter; stock engine & exhaust w/XPR Vortex on e-free super-u fuel.
About 90 degrees outside, coming out of a third gear corner, I landed off a 6-7' drop-off wide open accelerating up a tabletop and it died. As I was coasting up a tabletop giving it gas and it not running, I thought I hit the kill switch. I hit the starter button before I coasted to a stop and it fired right back up and ran normally the rest of the day. This happened at about 24hrs on the clock. I continued riding and I put another hour on it later that day; all good.
Rode the next weekend at a different track. It was about 75degrees out. Put another hour on it with zero issues (normal day). Never even thought about it cutting out.
Rode this last weekend @Washougal. It was hot out; between 95-106degrees. No problems 45min into the day until I landed the triple, butt-scrubbed the ant-hill after it and landed wide open (all normal, lap after lap) and it died again. No throttle, nothing. I coasted off the track & out of the way. This time I actually looked at the FI light and nothing. Hit the starter button and fired right up. Rode straight back to the pits as I knew I didn't hit the kill switch this time. I changed out the little stock inline fuel filter after a friend said he had some bogging issues that went away after changing out this filter. Went back out and rode another 10min moto with no issues and called it a day. It was 106 and I was smoked.
Having a bike die on the face of a jump can mean game-over, so I really want to find the root-cause. Even though I changed the inline filter, after chilling down and thinking about this (I'm mechanically inclined) I'm pretty confident that it was an electrical failure as it felt like hitting the kill switch. I would think a fuel problem would bog & chug a little not just be "done", but maybe not with fuel pumps. ???
So, I stripped off the plastic, seat and tank looking for any unintended exposed (worn-thru) wires, etc. I didn't find anything. I was suspicious of how my kill switch lead was routed and whether this could be an issue. After looking at the system it looks like the switch is normally closed and only opens the circuit (kills the engine) when grounded (or pressed). Meaning - if the engines running and you press the kill switch and let go quickly, the engine should sputter for a second but keep running.
I thought I'd throw this out here and see if anyone had any similar experience and what they found. Thanks!
About 90 degrees outside, coming out of a third gear corner, I landed off a 6-7' drop-off wide open accelerating up a tabletop and it died. As I was coasting up a tabletop giving it gas and it not running, I thought I hit the kill switch. I hit the starter button before I coasted to a stop and it fired right back up and ran normally the rest of the day. This happened at about 24hrs on the clock. I continued riding and I put another hour on it later that day; all good.
Rode the next weekend at a different track. It was about 75degrees out. Put another hour on it with zero issues (normal day). Never even thought about it cutting out.
Rode this last weekend @Washougal. It was hot out; between 95-106degrees. No problems 45min into the day until I landed the triple, butt-scrubbed the ant-hill after it and landed wide open (all normal, lap after lap) and it died again. No throttle, nothing. I coasted off the track & out of the way. This time I actually looked at the FI light and nothing. Hit the starter button and fired right up. Rode straight back to the pits as I knew I didn't hit the kill switch this time. I changed out the little stock inline fuel filter after a friend said he had some bogging issues that went away after changing out this filter. Went back out and rode another 10min moto with no issues and called it a day. It was 106 and I was smoked.
Having a bike die on the face of a jump can mean game-over, so I really want to find the root-cause. Even though I changed the inline filter, after chilling down and thinking about this (I'm mechanically inclined) I'm pretty confident that it was an electrical failure as it felt like hitting the kill switch. I would think a fuel problem would bog & chug a little not just be "done", but maybe not with fuel pumps. ???
So, I stripped off the plastic, seat and tank looking for any unintended exposed (worn-thru) wires, etc. I didn't find anything. I was suspicious of how my kill switch lead was routed and whether this could be an issue. After looking at the system it looks like the switch is normally closed and only opens the circuit (kills the engine) when grounded (or pressed). Meaning - if the engines running and you press the kill switch and let go quickly, the engine should sputter for a second but keep running.
I thought I'd throw this out here and see if anyone had any similar experience and what they found. Thanks!
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Typically, the failure I've seen is on the starter connection.
Like others have said, check all connections!
Good luck, nothing worse than these issues that make you paranoid
lol
I had some problems on my 17 450 SXF and ended up replacing fuel pump, fuel relay, rectifier, stator, and adding another ground from the battery to the frame under the fuel tank. Good luck, gets dangerous when your bike cuts out.
I've got it hot (pissing coolant) on the stand and pulled and pushed all over on the wiring harness and connectors to no avail. I've tested the connections and cleaned and re-affixed the battery/ground leads as well as you can (they weren't perfect, but they weren't bad either). I haven't found a smoking gun yet (haven't been able to recreate the failure). I was thinking about running an alternate ground strap to the main frame as well...
That filter/pump unit noted above may be my next direction - or, perhaps I pull the stock unit and test it for leaks, kinks, etc. first. I'm gunna race it this weekend with the cleaned/re-affixed battery straps and a lower RVP fuel and test.
Also....my KTM450 bogged at the top of an uphill triple and sent me over the bars with a broken wrist and concussion. Felt like the same thing.
It could be the routing of the fuel lines in the gas tank from what i have heard.
I know i'm all over the place with this but i'm not 100% sure that i ever found the problem
If you do this and ride in wildly varying temperatures like the PNW (100+ in the summer to 30-40's in the winter or colder), be sure to richen the pots back up. It's unlikely you could cause a lot of damage off the low & mid pot settings but might be possible. It would be easy to damage mis-adjusting the hi pot.
I have a 2023 husqvarna FS 450 that I have been racing all season with no issues, During my last race at Summit Point, West Virgina I experienced the same problem as MDana87. Coming down the front straight (114mph+), the engine would just shut off braking into turn 1. It was like i hit the stop switch. I rolled off into the grass, hit the start button, the bike started right back up. Got back into the race, down the front straight and the bike shut off braking into turn 1. Went back to the trailer, shut all the electronics off that I could (traction control, quick shift, launch control). Went out for my second race and it happened again in the same exact spot on the track. I know this is an old post but has any body found the problem. The only thing i think of electronically that could cuttoff the engine is the rollover sensor. I bought a new one and replaced the one on the bike but have not tested it yet.
Any help with this would be greatly appreciated.
It happened to me last month. 23 ktm450. Bike completely shut off on the face of a jump and put me in the hospital for 5 days. Broken right hip, broken left wrist, elbow, and separated shoulder.
It was a HOT day and I was just about past to 20 min mark. I still haven’t been able to go in the garage to look around the bike, but before my buddy brought it back home to me he got it fired up again. Said the main fuse was blown.
I really wanted to try out a fc350 for my next bike, but if I can’t find out what caused my bike to fail I’m not sure I can trust this generation of Austrian bikes which sucks because I am really enjoying the new chassis.
If not wiring behind front plate, fuel filters, then I would check all wiring under seat, remove/ pull back rear fender & make sure not crimped wires. I had same problem on my 22 350sfx, every once & while it would just die in middle of Moto for no reason, coast to a stop, wait a few seconds then fire right up. I brought it to a Ktm shop thinking electrical… stator tested fine, no wiring or sensor issues. The shop stated they sometimes come across bad coils and or coil wire & spark plug cap. What they ended up finding was my spark plug cap/ seal to valve cover was slightly raised, not sealing out water & mud. The spark plug cavity was totally plugged with sand/ mud, they could not get socket on plug. The tech felt after the engine got hot enough the spark would jump or ark out? So they dug out all the mud & eventually got the plug out, replaced plug & cap. Have not had an issue since…
Pit Row
Adding to the strange KTM fueling issue.
Recently I have had my bike essentially feel like it was running out of gas. The first time it happened I knew I had a full tank and it was over 100 that day. The problem occurred after a pretty hard landing. At first it sort of missed briefly, I kept riding around for a bit and felt like I ran out of gas.
2nd time happened yesterday at a different track. Very humid but only about 80 degrees and they had just added a ton of deep sand. So I am sure my bike was running a bit hotter than on the hard pack I am used to. Came over a triple, had a hard landing and when I went around the next corner, the bike essentially bogged about 1/4 throttle upwards.
After the first time it happened I pulled the pump assembly, double checked the injector, didn't backwash it though. The filters seemed normal, although I do have a new in tank filter I will install next.
What has me scratching my head is that the bike ran great a couple of times in between these rides, and it happened both times after hard landings. However, there were a couple of other hard landings my last rides in between, but there weren't drastic temp differences .
Just pulled the BB out of the gas cap, to see if it was vapor locking. And I leaned the mid adjustment a bit, but leaving the low and top.
Changing the in tank filter next, I did pressure test the pump the other day and peaked at 38 PSI, will test again after new filter.
If this doesn't fix it I am gonna swap out the rectifier since I have a 2nd one from the Quantum kit.
This is a Quantum pump btw. I don't actually suspect that the pump is bad. But I am worried about the crimp, as it was a bit loose last time I checked and I did my best to crimp it extra hard on re installation.
90% sure all my wiring is good, but I did notice that the wire pulled out of the 02 sensor attached to the air box. I am running a Vortex though and had read that this sensor doesn't work w the Vortex.
Reviving an old thread because this literally happened to me this weekend at Summit Point lol
Rode all day Shenny on Sunday, cut out once but fired right back up before pit in(luckily was checkered flag lap for trackday) then Monday, all morning was decent, ran out of gas once by my own fault, then in the afternoon it shut off into T1, fired back up, shut off again later. Let it sit for 3 sessions then on the last session it shut off into T10 and I just rolled into grass until session was over.
Fired right back up and rode to paddock.. any idea or advice?
An update to my earlier post….I had a bad Vortex in my 22 350SfX…only found that out when I sent it in to Twisted to be remapped for a 24 30SFX….Vortex warrantied me with a new box….so, if anyone is experiencing these symptoms and using a Vortex, try your stock box….
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