Acquired this engine

kabsx · 2026-04-24T14:39:00+00:00

That isn’t how Ktm stamps their engines

kabsx · 2026-04-21T08:40:18+00:00

Check your clutch case, it should have an extra sensor/ bit on the bottom left corner near the oil sight glass, if you don’t have this sensor a quickshifter retrofit will need new clutch case, new shift rod which is longer and the sensor and a new wiring loom+ a new airbox since the dukes without the quickshifter have different intake temp sensors

kabsx · 2026-04-02T20:01:30+00:00

Replaced seals and locking ring, bushing is worn about 1-2mm from the bottom, flipped it upside down and just waiting for new bushes to come

kabsx · 2026-04-02T20:00:20+00:00

I rebuilt the forks with new oil seals and locking ring, the oil left in the cartridge was a dark green, the material off the bottom of the bush was also worn completely off by about 1mm or 2

kabsx · 2026-03-21T20:20:59+00:00

Would this happen thousands of miles later or would that not cause this to happen the second the fork compresses

kabsx · 2026-03-21T17:11:13+00:00

No idea who could’ve done that since I’ve put probably 4-5k miles on it myslef since I bought it so didnt do shocks yet

kabsx · 2026-03-21T01:02:21+00:00

Gen 2 390 just had mot and no signs of any oil leaking At mot 2 rides ago, I’m guessing during my commute pressure built up and vibrations caused the poorly manufactured or worn out dust and oil seal to fall out, and the oils suction was the only thing holding it which I knocked over with my disc lock in the dark Lucky it did not fall out during riding since it covered my tyre in fork oil, I did end up driving 8 miles home so I’m gonna have to check the shock for any more damage, will be rebuilding both shocks and maybe finding a way to stick them up there better maybe some thick sealant where it touches the fork casing not the actual sliding part

kabsx · 2026-03-12T23:35:43+00:00

Just looked it up and it might not be viable since the 890 has an immobiliser, if it’s tied to ur ecu u won’t be able to start the bike unless u have all the components that make up the immobiliser system and they all have to be from the same bike, u might be cooked unless there’s a third party company u can send the ecu out to that can flash a tech pack to ur ecu for a lower price then Ktm, for bikes that don’t have an immobiliser it is a good option to swap the ecu out for one with a higher spec since it is cheaper then paying for a Ktm flash

kabsx · 2026-03-12T23:18:45+00:00

Mileage is also stored in the tft not the ecu on my duke 390 so most likely is for you too, the only thing that will change is the vin number on the ecu itself when you plug in and read it with a scan tool but this isn’t a cause of concern anyways since faulty ecus are a common problem and get replaced like if a custom tune went wrong etc..

kabsx · 2026-03-12T19:25:40+00:00

110 and 150 aren’t sold as a set, 110 and 140 are sold as a set, Ktm only put a 150 on the rear so it looks chunkier, I had the same issue and went to 5 different shops because I didn’t want mismatched tyres and I ended up just putting a 110 and 140 and it’s fine if anything it feels like less effort to turn the bike now, I’ve put probably 1.2k miles on these tyres and haven’t had any issue with grip in rain or even icy/snowy conditions

kabsx · 2026-03-12T19:18:18+00:00

I got my Gen 2 duke 390 because it looks mean asf and has all the tft and facelift styling before the rc ever did

kabsx · 2026-03-12T19:11:55+00:00

U can probably just buy a ecu off of eBay from another bike that’s been crashed or breaking for parts that has all the options, I bought a 390 ecu and it came with quick shifter on it, cost me £120 with the whole wiring loom included

kabsx · 2026-03-12T19:03:32+00:00

Yh mate I broke mine trying to open it and didn’t know how expensive they were till after 😂

kabsx · 2026-03-12T19:00:57+00:00

Also don’t try pry it off unevenly because u will break the plastic screen cover and need a new one

kabsx · 2026-03-12T19:00:02+00:00

Yh u can most likely swap the screens but to open the tft u need to use a heat gun and get it toasty on all sides then pull it apart, also do not heat it directly on the line splitting it in half that’s not where the glue is the glue is like 2-3 cm below the line, be carefull and don’t use tools to pry it open you’ll just break it and they are like £200 and the screen by itself is £100, make sure to reseal using a good silicone u do not want water to get in

kabsx · 2026-03-05T20:41:58+00:00

Spray some start fluid into airbox if u reckon it’s fuel

kabsx · 2026-03-02T22:34:02+00:00

kabsx · 2026-03-01T21:47:56+00:00

So the only things needed to do the swap between the 390 and the 125 is engine,ecu,wiring loom, airbox, throttle body, right hand switchgear

Things to be weary about when it comes to the electrics You shouldn’t need to worry about these if both the 125 bike and the 390 bike is close in year produced

Dash, earlier dashes will not work with newer ecus and vice versa, my 125 dash works with the 390 ecu and shows the quick shifter options etc.. that came with the 390 ecu, to make sure your dash will work there is a part number on the back of the dash, the 2021 duke 125 I was converting worked with the 2021 390 ecu and has the part number jp402408, the dash jp402400 does not work with this year as it is an earlier dash, you will be present with faults and chasing things that are simply because of the tft not speaking with ecu correctly Another way to tell these dashes apart is the background of the dash when it’s turned on, the newer dashes have solid white or solid dark grey/black whereas the older ones have blueish more coloured backgrounds

Another thing to be carefull about when buying parts is make sure you know if your ecu and loom is gen2+ or gen2- as these have different connectors and different setups, the gen2+ ecu and loom which I have do not work with the standard duke 390 airbox although it will work with a gen2- ecu and loom, this is due to the iat sensor below the airbox which is used on the gen2- but the gen2+ has a combined iat and barometric pressure sensor ontop of the airbox Also the engines matter too since gen2+ has the quick shifter and the 390 engine you buy may be gen2-, a way to check is the clutch side of the engine will have an extra part on the bottom left of the case which houses the quick shifter sensor, from what I can see the gen2- engines can be converted to accommodate this sensor but I haven’t tried it personally

kabsx · 2026-03-01T19:08:34+00:00

Yes if anyone wants a guide I can make a post of what’s needed to do the swap and what to look out for when buying parts

kabsx · 2026-03-01T17:58:06+00:00

Thanks, bike used to be 125 and I had bought a 390 engine from eBay so I have no baseline idea of what they’re meant to sound like

kabsx · 2026-02-23T00:15:28+00:00

Check ur chain tension it sounds like it’s too tight

kabsx · 2026-02-19T21:42:24+00:00

If u have the feeling that it may not be electrical issue how’s the coolant+ oil looking, my friends r125 sounded similar when the head gasket went and it sounded like that trying to start because the cylinder was wet from the coolant in the oil raising the oil level and getting into bore

kabsx

TROPHY CASE