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Ktm 150 xc-w throttle bog

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So I recently (yesterday) traded in my 2008 125 sx for an almost brand new 2017 150 xc-w with 3.2 hours on it, and almost every powerpart under the sun thrown at it apart from triple clamps and wheels. Today I took it for its maiden voyage and bottom end power was like nothing I've ridden before it was so smooth and tourqey for a bike this size, needless to say I'm well impressed. But as soon as I gave it some it bogged and bogged until it was on the pipe, I'm guessing the bike isn't jetted for the exhaust correctly (ktm powerparts fmf pipe and akrapovic short silencer). I Have no clue with the jetting that's in the bike but I do know it's the clourless powervalve spring that's in it at the moment. I plan to make this thread like a sort of long term ride report (kind of like what Ernie is doing with his thread). Suspension wise it's very soft and plush almost too soft but I'll adjust the settings as I go along. This is my first trail/enduro bike and I think I have the perfect package, on the 3rd of September I'm going to be doing my first xc/hare scramble so it'll be interesting to see how the bike performs. All in all this bike has everything I loved about the 125 and everything love about my dad's 350.2896a5015139678134eb899c9ddcaedf.jpg1ce9288a7f69d3cc8295430231d805f3.jpg

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So when you say "you give it some" are you saying that you're giving it 3/4 to WOT? Does it go booooooowaaanng or does it just rev really slow and it's kind of gutless and sign off early at WOT? Either way it could be the main jet. But just to make sure you do everything correct, do what theBIGnaud said, take it apart, check reeds, air leaks, float height, air filter(clean), and sparkplug. I know it's kind of a hassle as my 16' 150 SX has the hard intake boot so you have to do the subframe trick. Once you have checked everything over, and if everything seems good, THEN start playing with jetting. If there's something wrong, fix it, then go to recommended jetting on the KTM charts. If jetting is still wonky, when in doubt, go richer. If it makes it worse, then go leaner.

 

Sick bike btw :cool:

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Another thing to note is the bike was road registered when i got it so it has only ever seen tarmac, so really it could be jetted for absolute top end

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So when you say "you give it some" are you saying that you're giving it 3/4 to WOT? Does it go booooooowaaanng or does it just rev really slow and it's kind of gutless and sign off early at WOT? Either way it could be the main jet. But just to make sure you do everything correct, do what theBIGnaud said, take it apart, check reeds, air leaks, float height, air filter(clean), and sparkplug. I know it's kind of a hassle as my 16' 150 SX has the hard intake boot so you have to do the subframe trick. Once you have checked everything over, and if everything seems good, THEN start playing with jetting. If there's something wrong, fix it, then go to recommended jetting on the KTM charts. If jetting is still wonky, when in doubt, go richer. If it makes it worse, then go leaner.
 
Sick bike btw :cool:
No it sort of goes from bottom end to top end but in the middle of that it sputters like the choke has been left on rather than bogging out, but after you get past the sputter it screams and is unbelievably quick compared to the 125 I used to have.

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2 hours ago, Djsoggy said:

No it sort of goes from bottom end to top end but in the middle of that it sputters like the choke has been left on rather than bogging out, but after you get past the sputter it screams and is unbelievably quick compared to the 125 I used to have.

Sounds like my bike. My bike has a rich pilot for sure though. After idling for about 10 seconds then i take off, it sputters in the mid-range.

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Sounds like my bike. My bike has a rich pilot for sure though. After idling for about 10 seconds then i take off, it sputters in the mid-range.
I actually just changed the powervalve spring to the yellow one and it seems to be alot better, it's not 100% there but it's good enough for now, I'd say it's about 80% there.

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1 minute ago, Djsoggy said:
6 minutes ago, Arikno said:



Sounds like my bike. My bike has a rich pilot for sure though. After idling for about 10 seconds then i take off, it sputters in the mid-range.

I actually just changed the powervalve spring to the yellow one and it seems to be alot better, it's not 100% there but it's good enough for now, I'd say it's about 80% there.

Which spring was in there before? You might have a rich pilot.

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Which spring was in there before? You might have a rich pilot.
The colourless progressive one

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What jetting are you running? My bro in law has the same bike and we were down in the 420 main 30 pilot range in order for it to run right.

You'll probably want to pull the reeds out and check them for gaps. That will make response poor on the low end.

Also that new airbox design is really restrictive so getting some more air in there will help. Youtube "17 KTM airbox mod" it will show you a few tricks.

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More than likely, it's a Power Valve issue (sticking and not freely opening and closing), not the carb.

My bike now has about 7 hours after this past weekend. I installed the Lectron carb on mine and the bike has that 2nd and 3rd gear death bwoooaaaar bog. It's like the bike just took a dump. I've tuned the Lectron 3/4 turns in both directions "rich and lean"....guess what? Same F'ing "BOG" in ALL situations....it's irritating. After chatting with a few others at KTM Talk....their bog experiences went away after some break in time. We're talking like 10+ hours.  Here's another reference link  http://ktmtalk.com/showthread.php?537325-150-power-valve-issues&p=5159041#post5159041       the 2nd pic of the PV part (drum, roller?) could be sticking (not rotating cleanly) and could be a contributing culprit.

I know it's not the Lectron cuz I have one on my '17' 250xcw...absolutely no issues there.

However, once out of that weird RPM range (2k'ish to 3500?) where the bog resides and with some throttle and clutch feathering...the bike runs great.

I've also ordered the aftermarket F1Moto Power Valve Arms from the "land of OZ" as a "just in case"....the arched roller track is designed smoother than OEM. We shall see once they arrive, and hopefully not a waste of $100.

pv arms 125-150.jpg

CAM00618.jpg

Edited by hopsterj

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4 hours ago, hopsterj said:

More than likely, it's a Power Valve issue (sticking and not freely opening and closing), not the carb.

My bike now has about 7 hours after this past weekend. I installed the Lectron carb on mine and the bike has that 2nd and 3rd gear death bwoooaaaar bog. It's like the bike just took a dump. I've tuned the Lectron 3/4 turns in both directions "rich and lean"....guess what? Same F'ing "BOG" in ALL situations....it's irritating. After chatting with a few others at KTM Talk....their bog experiences went away after some break in time. We're talking like 10+ hours.  Here's another reference link  http://ktmtalk.com/showthread.php?537325-150-power-valve-issues&p=5159041#post5159041       the 2nd pic of the PV part (drum, roller?) could be sticking (not rotating cleanly) and could be a contributing culprit.

I know it's not the Lectron cuz I have one on my '17' 250xcw...absolutely no issues there.

However, once out of that weird RPM range (2k'ish to 3500?) where the bog resides and with some throttle and clutch feathering...the bike runs great.

I've also ordered the aftermarket F1Moto Power Valve Arms from the "land of OZ" as a "just in case"....the arched roller track is designed smoother than OEM. We shall see once they arrive, and hopefully not a waste of $100.

pv arms 125-150.jpg

CAM00618.jpg

Hmm interesting, was thinking about this today. At work.  Prolly shouldn't have. LOL! Has the owner tried checking stator timing? Have you checked the spark plug(strange colors, insulator chipped, electrode eroded, excessive or too small gap, ect). Bad factory coil, WOT, loaded power, throttle snapping shut will suffer if you coil is defective. What is the mechanism the retards and advances spark timing? I would look there as well..I normally have these issues with a defective distributor on hot rods..

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Save yourself the headaches and time and buy the JD kit. The stock mikuni jetting sucks and I ignored everybody and tried every combo out there and finally bought the JD. Problem solved!

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Here, enjoy the read, 2 separate threads provided....since the 16's and 17's (125/150) are basically the same motor parts (regardless of SX or XCW). This is referring to the Power Valve Barrels that rotate. The Barrels themselves, PV Arms, and/or the the Cylinder manufacturing is apparently is not the smoothest.

Read through the top 2 main threads (Power Valve issue).....I'm not saying every bike has this scenario, however, the threads present the bike's problem, cause, effect and fix.

https://www.google.com/search?q=vitalmx+150+power+valve&oq=vitalmx+150+power+valve&gs_l=psy-ab.3...567461.568516.0.568922.4.4.0.0.0.0.94.258.3.3.0....0...1.1.64.psy-ab..1.0.0.3-oSh6bLV48

https://www.google.com/search?q=vitalmx+125+power+valve&ie=utf-8&oe=utf-8

Edited by hopsterj

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7 hours ago, theBIGnaud said:

Hmm interesting, was thinking about this today. At work.  Prolly shouldn't have. LOL! Has the owner tried checking stator timing? Have you checked the spark plug(strange colors, insulator chipped, electrode eroded, excessive or too small gap, ect). Bad factory coil, WOT, loaded power, throttle snapping shut will suffer if you coil is defective. What is the mechanism the retards and advances spark timing? I would look there as well..I normally have these issues with a defective distributor on hot rods..

I am an owner.....just curious, do you own a '17' 150?

Btw, the bike has the VForce Reeds, the RK Tek head insert and the Lectron carb as mentioned above.

Edited by hopsterj

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I had same issues with jetting. I ride the bike in slow technical terrain. the carburetor really loads up in the slow going. I had to put a 25 pilot on the mikuni to fix the bog when hitting a climb after putting around in the tight woods. same with the lectron. 1 1/2 turn leaner on the metering rod. I really like that bike.

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17 hours ago, hopsterj said:

I am an owner.....just curious, do you own a '17' 150?

Btw, the bike has the VForce Reeds, the RK Tek head insert and the Lectron carb as mentioned above.

No but I am a master tech. Seems like you bought something with a factory defect, if it is truly the power valve linkage, i would be taking it back to the dealer or local machinist and charging the dealer back for parts and labor (if they tell you to take a hike). if it is not power valve linkage, if you want to truly get you bike back to normal, install the FACTORY parts and start eliminating errors in your intake combination.

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Post your current jetting..

As mentioned before, the JD jetting works great. 

And in addition to the JD kit go to a leaner slide, get yours cut or buy one. This helps the transition onto the needle, i feel it's needed even with the JD kit. #4 is stock which is very rich, #5 or leaner is needed. 
 

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On 8/23/2017 at 6:34 PM, theBIGnaud said:

No but I am a master tech. Seems like you bought something with a factory defect, if it is truly the power valve linkage, i would be taking it back to the dealer or local machinist and charging the dealer back for parts and labor (if they tell you to take a hike). if it is not power valve linkage, if you want to truly get you bike back to normal, install the FACTORY parts and start eliminating errors in your intake combination.

Thx TBN....scenario's been narrowed down. Basically, the motor is just seeming to "load up" (my first small bore)...along with a little help from some sticking power valve components.

Popped the PV covers, removed the PV rod and there was stiction with the entire assembly....so, pulled the PV Drums, Lock Plate and PV Arm assembly....don't think the OEM Arms are actually bad. The aftermarket Arms were actually worse and didn't really fit onto the Flapper without some sort of machining effort...LOL, decided not going down that path....toss of $100 in the trash or use as interesting Xmas ornaments.

Removed the PV Lock Plates and Drums, cleaned them really good (buffed the plate sides that face the Drums) and re-installed with Ultra Slick engine build lube...bingo, very nice clean PV assembly butter smooth movement, no more Drum Pin stiction in the PV Arm Arcs.

Going to try the "lean direction" 1 to 1.5 turns on the Lectron next....oh, another thing, give the Red Spring a whirl in the 150 (I have a Blue Spring ordered, it's between the Red and Yellow)....I tuned the Dolly in 1 full turn CW from full out CCW flush, ME LIKE IT !!! and a pleasant surprise.  Typically run the same setting with my 250...it works great.

Cheers

 

Edited by hopsterj

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On 8/25/2017 at 6:59 PM, hopsterj said:

Thx TBN....scenario's been narrowed down. Basically, the motor is just seeming to "load up" (my first small bore)...along with a little help from some sticking power valve components.

Popped the PV covers, removed the PV rod and there was stiction with the entire assembly....so, pulled the PV Drums, Lock Plate and PV Arm assembly....don't think the OEM Arms are actually bad. The aftermarket Arms were actually worse and didn't really fit onto the Flapper without some sort of machining effort...LOL, decided not going down that path....toss of $100 in the trash or use as interesting Xmas ornaments.

Removed the PV Lock Plates and Drums, cleaned them really good (buffed the plate sides that face the Drums) and re-installed with Ultra Slick engine build lube...bingo, very nice clean PV assembly butter smooth movement, no more Drum Pin stiction in the PV Arm Arcs.

Going to try the "lean direction" 1 to 1.5 turns on the Lectron next....oh, another thing, give the Red Spring a whirl in the 150 (I have a Blue Spring ordered, it's between the Red and Yellow)....I tuned the Dolly in 1 full turn CW from full out CCW flush, ME LIKE IT !!! and a pleasant surprise.  Typically run the same setting with my 250...it works great.

Cheers

 

Good to hear! i would give the local dealership an earful and show them a bill or two. In MY professional opinion, the dealership should hear this feedback from new owner customers. (IE: Chevy, Lexus ect ect.) It will improve their reputation and their machines. It seems KTM has been skimping on either "outsourcing" or assembly inspections, this reoccurring problem MAY cost them dearly now that they have lost an all star rider.

Yes there is a fix... for a 9500 bike, that's about 1500 bucks too much. that is about a privateers costs for; fuel and fluids/clutchs for a racing season. Trust me, no one wants to race a machine that has EVEN a inclining of POSSIBLE factory issues with their race engines I hope their oil injection systems don't suffer the same consequence. 

I am gunna go ride now!

 

I am die hard KTM fan.. since the 90's.

 

One more question, does it look like the mechanisms are receiving enough lubrication? possibly some APPROVED grease to go along with the reassembly of the mechanism?

Edited by theBIGnaud
no proof read
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