2015 RC390//Duke cheap slipper clutch upgrade OEM

ShawnB

New Member
2015 KTM RC 390 OEM slipper clutch upgrade cheap


Purchase a clutch pack from a 2016, 2017, 2018 KTM RC390 or Duke 390 (inner clutch hub, friction and steele plates, washers, everything but the clutch basket. You should also get a new gasket for the clutch cover.


USED OEM KTM DUKE/ RC390 CLUTCH KIT

  • PART# 90232111010 eBay ~$70-$120

slipper inner ktm.jpg
slipper outer ktm.jpg
GASKET CLUTCH COVER


90230027000 $3.23


Drain oil


Loosen or disconnect clutch cable


Remove the clutch cover


Remove the clutch pressure plate (5 bolts 10mm)


Remove the the clutch holding nut REVERSE THREAD, so loosen by turning clockwise.


I used a Tusk clutch holding tool and a breaker bar with socket. Since this is a budget project if you don't want to buy the tool $19.99 you can put a strap on the clutch hold it in place. It will squeeze in there without damaging anything while you turning the nut. Here's a crappy youtube vid I found of that process https://youtu.be/uxRlr8iSGA4
I've also used a towel between the primary gear before and that works also. Neither is really recommended but they do work.

Remove the old clutch pack, but leave the old clutch basket in place.

Your new/used eBay slipper clutch will need to be disassembled prior to reinstall, so do that by taking off the 3 bolts hold the pressure plate on, should be a bearing, a pulling pin, washers in there loosely keep all of them and set aside. Take out the friction and steel plates and keep everything in its proper order so you don't get confused.

Inspect the friction plates and make sure they have enough friction material on them, mine were good, and if they aren't swap them out for your old ones. They are the same for the slipper and the OEM original I believe. Or buy new ones if you want.

Install the new clutch inner hub, then two big ring washers, the one that is convex (Bellville washer) should be on the outside.


Install the friction and steel plates alternative friction to steele. Oil the plates too a bit. Should be two smaller friction plates on the outside near the pressure plate and one inserted first into the clutch hub, the rest are slightly bigger. A parts diagram helps if you get confused. I always use one of these to make sure all of my parts are in the right place and you can find them online at KTM Parts Directory. KTM.SparePartsFinderFrontend

Here is a pic I took while putting it back together before I tighten up the clutch springs and pressure plate.
Screen Shot 2018-05-02 at 2.24.07 AM.jpg




Install clutch nut and the two washers that go with it.
Needs torque (88.5ft/lb) so use a torque wrench or good and tight with a breaker bar along with the clutch holding tool REVERSE THREAT so counterclockwise tightens.


Insert the clutch pulling pin and bearing that it rests against


Install the clutch pressure plate, clutch springs, and bolts (3 10mm do not over torque) Just stop when they bottom out.


New gasket for clutch cover or clean the existing and mating surfaces really good with brake/parts clean and compressed air.


Put the clutch cover back on a make sure to line up the clutch pull pin with the actuating arm. It needs to grab the pin and pull it when you squeeze the clutch lever so make sure it is in there good and working correctly by installing just a couple of clutch cover bolts and testing for proper pull. It should feel just the same as your standard clutch pull. You can also put bike into gear, pull in clutch and rotate the rear wheel, if it rear wheels turns while you are squeezing clutch lever it is actuating the pull pin properly.


Finish putting it back together by installing the cover and bolts (don't over torque these) and the cable. Adjust the cable tension to your personal preference, there should be a couple mm of freeplay in the cable before engagement takes place.



Fill with oil.


Start it up and circulate the oil then take it for a spin to test it.


No more annoying wheel hop on downshift :)






The way the slipper clutch works is there are ramps inside the inner clutch basket. When you down shift and let off of the throttle back pressure is created which transfers through the driveline to the back wheel
The engine braking w/o the slipper clutch installed with cause the back wheel to start locking up and hopping around unsettling the bike. This seems prominent on the RC390 enough to make it a worthwhile upgrade especially in a track day/race bike.


The slipper clutch uses the engine braking back pressure to push the plates apart with the force generated by sliding up on the inner clutch basket ramps. The force allows the clutch to momentarily slip relieving the load on the driveline and to the back wheel. This keeps the bike planted and maximized engining braking without locking up the rear wheel or unsettling the chassis.


Any questions message me..


Here are some pics of my bike

Screen Shot 2018-05-02 at 2.34.33 AM.jpgScreen Shot 2018-05-02 at 2.34.43 AM.jpgScreen Shot 2018-05-02 at 2.34.55 AM.jpg


My 3 children and wife wanted their favorite animals on my bike so that's on my gas tank baby elephant (9month old baby son Nico, baby tiger 5 year old son Reese, polar bear 7 year old daughter Jaelyn, and my wife Julia loves pandas :)








 
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mdabyo

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nice job! if you see another one pop up on ebay let me know.. i have been hunting since i saw your initial post.. lol
 

ReidMcT

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Complete new clutch kit is $122.50 from partsfish.com. Somebody on eBay is seeking a greater fool to pay over $200 for the same thing.
 

Foolishboy

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Anyone else had dramas getting the clutch actuating arm and pin to line up again? Just can’t seem to get it, or else I’ve done something else wrong.
The arm goes back in but when I pull the clutch lever in or turn the arm manually the rear wheel still doesn’t turn.

just about to pull it all apart again to check it all again, the parts diagram isn’t super clear when it comes to the clutch pull pin, bearings and spacers and washers.
 

ReidMcT

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... but when I pull the clutch lever in or turn the arm manually the rear wheel still doesn’t turn.

Huh? Can you explain what you mean by this? It makes no sense to me. You seem to be expecting the rear wheel to turn if you pull the clutch lever; I can't imagine why.
 

Tirefriar

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I've been looking into upgrading stock 2015 clutch to a slipper clutch. reviews on the OEM slipper clutch make it sound marginal at best. at the same time i don't want to dump a boat load of $$ on a yoyodyne. what are my options?
 

kostean

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KTM OEM slipper clutch performs rather ok as been racing these for few seasons. At the dry conditions, the back wheel hop is certainly reduced and I don't see a major advantage of Yoyodine. Different is when racing on wet conditions, where KTM set is still rather robust and you need to be careful on downshifting while at lean as engine braking is transferred to back weel.
 

Tirefriar

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KTM OEM slipper clutch performs rather ok as been racing these for few seasons. At the dry conditions, the back wheel hop is certainly reduced and I don't see a major advantage of Yoyodine. Different is when racing on wet conditions, where KTM set is still rather robust and you need to be careful on downshifting while at lean as engine braking is transferred to back weel.

Just the kind of info I was hoping to get. I don't track in the wet, will need to source a KTM OE slipper clutch pack. I tried a link listed above but its listing assembly for the Duke 390 only. RC application is a list of parts... Any guidance in that direction is greatly appreciated.
 

Foolishboy

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Huh? Can you explain what you mean by this? It makes no sense to me. You seem to be expecting the rear wheel to turn if you pull the clutch lever; I can't imagine why.
ok Bike is up on stands, so if I pull in the clutch lever with the bike in gear I should be able to turn the rear wheel by hand, as it is I can’t.
Every time I tighten up the main clutch retaining nut I can no longer turn the inner clutch hub at all.

hoping someone has a clear parts file or instructions of everything, not sure if I’ve missed something or what.
Did manage to find a good video showing rebuilding an engine which had the clutch in there but I don’t speak Hindi so hard to figure that out too.
 

Foolishboy

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Think I just worked it out, threw the old clutch hub on and no problems with turning, compared the pair and what do you know, missed a washer on the back.
Fingers crossed now, need to get this done for my first race day this weekend.
 

Johnnyboy69

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KTM OEM slipper clutch performs rather ok as been racing these for few seasons. At the dry conditions, the back wheel hop is certainly reduced and I don't see a major advantage of Yoyodine. Different is when racing on wet conditions, where KTM set is still rather robust and you need to be careful on downshifting while at lean as engine braking is transferred to back weel.
did you use the stock clutch basket or the clutch basket with the slipper clutch?
 
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