Posts
478
Joined
7/16/2019
Location
Tulsa, OK
US
O&GDriller
10/5/2020 10:13am
10/5/2020 10:13am
Edited Date/Time
10/9/2020 1:21pm
I recently replaced the clutch plates, steel and friction, in my 160 hour 2019 KTM 450 SX-F as it was slipping a bit due to wear. I replaced with the microfische called for OEM clutch pack KTM part number 79532010033 consisting of:
qty 8 lining disc part # 79532011000 1.95 mm
qty 7 intermediate disc part # 59032010200 1.4 mm
qty 1 intermediate disc part # 59032010100 1 mm
qty 1 intermediate disc part # 78932010000 1 mm
Problem I ran into is the newly installed clutch was not releasing/dragging when the bike was running. I was puzzled as the install went without issue.
Long story sort is the issue I discovered is the stipulated clutch pack does not provide what came with the bike from the factory. My son has an identical bike with the factory original/as delivered clutch still in it so I took his apart to have a look see. I discovered he only had one 1 mm intermediate steel disc, not the two called for in ALL documentation/parts fiches I've seen and read anywhere. I took his clutch pack out and put it in my bike and my observation was confirmed as my bike functioned flawlessly with my sons clutch installed. The clutch pack out of his bike as provided from the factory consisted of 8 - 1.4 mm steel plates and 1 - 1 mm plate. It DOES NOT have 2 - 1 mm steel plates, only one.
I'm totally baffled that I've not read of any other KTM owner having this same problem. ANYBODY changing a clutch pack in a current 450 would experience the same problem and have difficulty diagnosing if they didn't have an identical bike to use for comparative purposes. The wrong clutch pack is specified for a replacement. Only one 1 mm plate is required, not 2 as provided and stipulated in the parts catalogs.
As such my stack was 0.4 mm too short resulting in the clutch dragging. What really sucks is my "new" and incorrect $125 clutch pack was destroyed as I rode the bike with the clutch dragging while I was trying to figure out what was going on. It destroyed/burnt half the "new" friction and steel plates resulting in my having to buy another clutch pack. I'll have to reuse one of the "old" 1.4 mm steel plates in the second replacement clutch pack I'm now buying as it will also come with 2 - 1 mm steel plates.
Frustrating and puzzling. Any thoughts???
qty 8 lining disc part # 79532011000 1.95 mm
qty 7 intermediate disc part # 59032010200 1.4 mm
qty 1 intermediate disc part # 59032010100 1 mm
qty 1 intermediate disc part # 78932010000 1 mm
Problem I ran into is the newly installed clutch was not releasing/dragging when the bike was running. I was puzzled as the install went without issue.
Long story sort is the issue I discovered is the stipulated clutch pack does not provide what came with the bike from the factory. My son has an identical bike with the factory original/as delivered clutch still in it so I took his apart to have a look see. I discovered he only had one 1 mm intermediate steel disc, not the two called for in ALL documentation/parts fiches I've seen and read anywhere. I took his clutch pack out and put it in my bike and my observation was confirmed as my bike functioned flawlessly with my sons clutch installed. The clutch pack out of his bike as provided from the factory consisted of 8 - 1.4 mm steel plates and 1 - 1 mm plate. It DOES NOT have 2 - 1 mm steel plates, only one.
I'm totally baffled that I've not read of any other KTM owner having this same problem. ANYBODY changing a clutch pack in a current 450 would experience the same problem and have difficulty diagnosing if they didn't have an identical bike to use for comparative purposes. The wrong clutch pack is specified for a replacement. Only one 1 mm plate is required, not 2 as provided and stipulated in the parts catalogs.
As such my stack was 0.4 mm too short resulting in the clutch dragging. What really sucks is my "new" and incorrect $125 clutch pack was destroyed as I rode the bike with the clutch dragging while I was trying to figure out what was going on. It destroyed/burnt half the "new" friction and steel plates resulting in my having to buy another clutch pack. I'll have to reuse one of the "old" 1.4 mm steel plates in the second replacement clutch pack I'm now buying as it will also come with 2 - 1 mm steel plates.
Frustrating and puzzling. Any thoughts???
The Shop
You might reread my post.
Edit: Finally read the entire post. You burnt up the new pack? That’s usually called slip, not drag. I see where the shorter pack could cause this, but it’s still odd because there should be room for 0.4 mm wear without slipping. Also, every KTM DDS I know of uses two 1mm plates, not one.
Are you on the OE slave cylinder? Flushed the fluid recently?
My issues were the clutch was dragging when stopped in gear. With clutch lever pulled all the way to the bars there was considerate drag/lack of disengagement.
Additionally, when under power on track it was slipping due to shorter stack not receiving "enough" pressure from the spring.
With my sons clutch pack I had zero drag and it didn't slip under power.
FWIW, I'm sharing this info so others might not have the same problem. I have no agenda...
Regarding your son’s bike: Either all the KTM literature and fiches are wrong, or his bike got 8 1.4mm plates by mistake.
FWIW, I have a ‘19 Husky 450 and it has two 1mm plates.
The KTM belleville resembles the force-adjusting variety at the bottom of this page:
https://bellevilleintl.com/engineering/load-vs-deflection/
I had a similar issue with my 300, comparing the two parts dia. they look the same.
I don't know if the 450 has an x,y,z adjustment on the spring ring, but if it does that's
probable the issue.
I had to readjust the spring tension from the stiffest setting ...where it was set which I think is X, to the Y setting.
Also the washer (ktm calls it) that sits under the belleville spring is directional....should have "top" stamped on it.
Too much spring tension will cause excessive drag.
Post a reply to: KTM Clutch Observation/Issue - Anyone Else???