Clutch Gave Out

[gaumer94]

So on my way home today i noticed my clutch was slipping which is odd because i barely hit 2k on the bike. about a half an hour in the clutch gave out and now will not engage at all. I changed the oil about 500 miles ago with motorex. Has anyone else experienced this. also does anyone have a clue as to what happened before i start tearing it down so i know what im dealing with. EDIT: There was no scent of a burning clutch and there was play in the lever

 

[Deleted member 452]

Mine just started slipping @ 5.1K and is in the shop for repair under warranty.

 

[gaumer94]

Well i found the issue.... Went ahead and tore the bike down. The nut that holds the inner hub came off!!! Luckily its warrantied because it damaged the threads on the shaft.

 

[Deleted member 452]

I wonder if that's my problem... I had the dealer put in a shift kit when they were replacing the head gasket @ 4.3K miles but before replacing the water pump at 4.7K miles (My bike is crap) so they may have not used locktight or the correct torque. I'll should find out in another week.

 

[stevieboy]

I hope to never be in the place where you say 'my bike is crap'. But I am looking for my fourth FZR400.....

 

[gaumer94]

Kind of sad going through the bike and looking at the quality (or lack there of) of some of the components on the bike. i understand its a budget bike but having a couple of ktm 450s this isn't the quality you expect from ktm...

 

[green_bread]

Had the same thing happen with the nut backing off during one of my races. I got lucky and nothing was damaged, though. Sorry to hear about the bad luck.

 

[Ryanthegreat1]

Oh yay, another chance to pull the clutch cover off and check that a fastener was properly torqued.

How long before we need to start checking rod bolt torque. Geez.

 

[Fasteddy]

Oh yay, another chance to pull the clutch cover off and check that a fastener was properly torqued.

How long before we need to start checking rod bolt torque. Geez.

In the earlier days of ownership the thought of just buying a complete engine, tearing it down and re assembling it went through my mind...

 

[Chris The Welder]

Question for the guys this has happened to, when the bolt comes lose does it give you any warning at all?

 

[Seth]

Had the same thing happen with the nut backing off during one of my races. I got lucky and nothing was damaged, though. Sorry to hear about the bad luck.

Lucky catch!

 

[green_bread]

Question for the guys this has happened to, when the bolt comes lose does it give you any warning at all?

Yes, actually. At least, it did for me. Basically, the clutch lever stopped returning all the way back out and just progressively got worse as the nut backed off more. Eventually, you could pull the lever and the only resistance to overcome was the return spring, which isn't much, and the clutch wouldn't disengage at all.

Again I say, I got VERY lucky that nothing was damaged. I don't recommend to keep riding if yours starts doing this.

 

[gaumer94]

same exact process happened when mine back out as well. Mine went out on the 710 (for all you la people) at about 6 in the afternoon (ridiculous traffic) so I had to split lanes until it got clear enough for me to get over. Lol talk about a butt pucker situation

 

[Diploman]

The 2013 MY 390's had a spec of 80 NM for the (left-hand thread) nut which holds the clutch inner basket. There was a rash of failures as the nut loosened and often separated from the shaft. In 2014 KTM revised the factory spec for this nut to 120 NM (88.5 ft/lbs), in addition to specifying Locktite 243 (blue). This new spec appeared to address the problem, but now the bikes that have the most extreme usage (ie the racers) seem to be exceeding in some cases what the new spec can accommodate. Perhaps a new, stouter spec is needed: It is unclear whether torquing beyond 120 NM is safe; however, red Locktite would be a possible spec augmenter. This would add some hassel to clutch repairs/upgrades, but if it kept the clutch together at max throttle, it might be worth it.

 

[Treachery]

Yes, actually. At least, it did for me. Basically, the clutch lever stopped returning all the way back out and just progressively got worse as the nut backed off more. Eventually, you could pull the lever and the only resistance to overcome was the return spring, which isn't much, and the clutch wouldn't disengage at all.

Again I say, I got VERY lucky that nothing was damaged. I don't recommend to keep riding if yours starts doing this.

The 2013 MY 390's had a spec of 80 NM for the (left-hand thread) nut which holds the clutch inner basket. There was a rash of failures as the nut loosened and often separated from the shaft. In 2014 KTM revised the factory spec for this nut to 120 NM (88.5 ft/lbs), in addition to specifying Locktite 243 (blue). This new spec appeared to address the problem, but now the bikes that have the most extreme usage (ie the racers) seem to be exceeding in some cases what the new spec can accommodate. Perhaps a new, stouter spec is needed: It is unclear whether torquing beyond 120 NM is safe; however, red Locktite would be a possible spec augmenter. This would add some hassel to clutch repairs/upgrades, but if it kept the clutch together at max throttle, it might be worth it.

Good information from you both. Thanks!

 

[Martin85]

Is a easy and u can fix by yourself too...I try before when launch bike...Once I release the clutch it directly no working anymore and wheelie,best safe ever...
Back to the topic,if u facing this problem is no need to send to the dealer,how to fix:
~u need to know how to ride with clutchless style,up or downshift without apply the clutch,keep clutchless up and down shift on gear3-5...Speed around 20-60kmh, downshift matching engine speed,once the clutch hit the sweet spot...It will back to normal...I know this can fix because that day I just ride like this, starting I'm not sure,1 day I go the dealer shop and they just receive the same case,I say let me try to fix...After few minutes I ride back the bike...Problem sorved