04 KTM 625 SMC Clutch Mushy in 5th Gear - BARF

infecto · 09-16-2020, 12:46 PM

Never experienced this before but maybe someone can point me in the correct direction. Recently got this bike, runs great but the clutch actuation is mushy in 5th gear (top gear).

As far as I can tell I have not experience slip in the clutch but going to do a more in depth test. Shifts through gears fine, clutch feels great until it hits 5th. 1-4 the actuation of the lever is snappy and the level of resistance feels fine. Once in 5th, the amount of resistance of the lever goes down and it only it feels like it only goes out about half of the way (lever).

Some things on my list that I am going to do
- Change engine oil
- Change clutch hydraulic fluid
- Look into if there are any special adjustments for the clutch (I would except to feel it in all ranges though but not experienced here)
- If all else fails pop open the clutch to see if anything is obvious and perhaps replace the clutch plates.

ST Guy · 09-16-2020, 01:18 PM

Weird. I can't think of anything that would affect the clutch in just top gear.

Does it snick into the top gear just as easily and precisely as the other gears?

infecto · 09-16-2020, 02:16 PM

Quote:

Originally Posted by ST Guy

Weird. I can't think of anything that would affect the clutch in just top gear.

Does it snick into the top gear just as easily and precisely as the other gears?

Yeah it went into top gear fine and felt the same. Everything was the same except for the feeling in the clutch lever.

BUT I am going to test it out again today more precisely then do an oil change and test it out again.

infecto · 09-24-2020, 07:30 AM

So i did get around to changing the oil and no change. Going to try changing the hydraulic clutch oil now.

Dmitriy · 09-24-2020, 08:12 AM

So you can try changing the slave piston o-ring
It's the same the the output shaft o-ring 0770250021 (25mm x 2mm)
And reverse bleed the clutch system with a syringe
Mushy feel would be that imo. (Those bikes are old enough that the specific o-ring wears out by now)
Nothing in the operation of the clutch will be different between the gears as the shifting drum has no effect on the push rod and vice versa.

ST Guy · 09-24-2020, 10:39 AM

And that's why it's a head scratcher. If it's "mushy" in one gear, it should be "mushy" in all gears.

Dmitriy · 09-24-2020, 11:07 AM

Quote:

Originally Posted by ST Guy

And that's why it's a head scratcher. If it's "mushy" in one gear, it should be "mushy" in all gears.

Of course his needle bearing/case pocket on the cluch slave side could be getting 'eaten' by the transmission shaft and thus the larger 5th gear is putting more load on the shaft, however he would have reported a ton of metal flake in the oil if that was the case.

infecto · 09-24-2020, 09:07 PM

Agree on all accounts. My assumption would be that it should be a static feeling across all gears and across all speeds.

I guess to further describe the feeling further. All other gears feelings more in line with my experience on different bikes. At speed when I get into 5th gear and let off the clutch it engages with the lever at around 50% out and then just stop moving. Making sure I am not mixing up terminology here. So by mushy what I am saying is the clutch is only going back out about 50% when I release it.

No excessive metal shavings, there was some dark flakes which I assume might be clutch. From pictures I have seen from other oil changes it did not look too excessive and while I usually dont judge oil by the color as its not accurate...this had a viscosity that just looked awful so I am guessing its been a bit since it was last changed.

I will do as described o-rings and I might also rip open the clutch cover and see what I see. Never had to touch a cluth or gone that far on maintenance before but will see what I can see.

CDONA · 09-25-2020, 09:39 AM

What did the oil smell like?

If the plates are slipping there should be a burned clutch/brake pad smell with darkened oil

Using wet clutch moto oil?
Some high milage auto oils will run an additive that will let bike clutches slip.

ST Guy · 09-25-2020, 04:36 PM

I think at this point it would be advised if someone else more familiar with your bike would ride it and give their opinion. Things just aren't adding up.

motomania2007 · 09-25-2020, 06:32 PM

Has me thinking that possibly due to 5th being very tall would change engine dynamics

infecto · 09-26-2020, 03:16 PM

If anyone would be gracious enough to test ride it I am down hah.

I was playing around with it more, it does seem to be a engine dynamic. I dont notice it in 5th gear low speed. Only highway speeds in 5th gear.

Edit: Did not notice any burnt smells, even compared to some other used oil.

09-16-2020, 12:46 PM	#1
infecto Rookie Join Date: Aug 2019 Location: Oakland Motorcycles: Versys 1000 Ninja ZX-6r Name:	04 KTM 625 SMC Clutch Mushy in 5th Gear Never experienced this before but maybe someone can point me in the correct direction. Recently got this bike, runs great but the clutch actuation is mushy in 5th gear (top gear). As far as I can tell I have not experience slip in the clutch but going to do a more in depth test. Shifts through gears fine, clutch feels great until it hits 5th. 1-4 the actuation of the lever is snappy and the level of resistance feels fine. Once in 5th, the amount of resistance of the lever goes down and it only it feels like it only goes out about half of the way (lever). Some things on my list that I am going to do - Change engine oil - Change clutch hydraulic fluid - Look into if there are any special adjustments for the clutch (I would except to feel it in all ranges though but not experienced here) - If all else fails pop open the clutch to see if anything is obvious and perhaps replace the clutch plates.

09-16-2020, 01:18 PM	#2
ST Guy Veteran Join Date: Nov 2006 Location: South Bay Motorcycles: Honda ST1100 ABS (tweaked here and there) Name:	Weird. I can't think of anything that would affect the clutch in just top gear. Does it snick into the top gear just as easily and precisely as the other gears? __________________ It's not the answer that enlightens, but the question. - Eugene Ionesco Let us not pray to be sheltered from dangers but to be fearless when facing them. - Rabindranath Tagore A mind all logic is like a knife all blade. It makes the hand bleed that uses it. - Rabindranath Tagore

09-24-2020, 10:39 AM	#6
ST Guy Veteran Join Date: Nov 2006 Location: South Bay Motorcycles: Honda ST1100 ABS (tweaked here and there) Name:	And that's why it's a head scratcher. If it's "mushy" in one gear, it should be "mushy" in all gears. __________________ It's not the answer that enlightens, but the question. - Eugene Ionesco Let us not pray to be sheltered from dangers but to be fearless when facing them. - Rabindranath Tagore A mind all logic is like a knife all blade. It makes the hand bleed that uses it. - Rabindranath Tagore

09-25-2020, 09:39 AM	#9
CDONA Home of Vortex tuning Join Date: Jul 2010 Location: Based in Spearfish SD. rolled over there > Motorcycles: Triumph scrambler, TW200, Monkey Name: # 44659	What did the oil smell like? If the plates are slipping there should be a burned clutch/brake pad smell with darkened oil Using wet clutch moto oil? Some high milage auto oils will run an additive that will let bike clutches slip. __________________ "Chip Tank" in Hope Az. All I want for Xmas is my two vaccines Started hammerin' Honda 90's around Berryessa, Summer of Love '67 Last edited by CDONA; 09-25-2020 at 09:42 AM..

09-25-2020, 04:36 PM	#10
ST Guy Veteran Join Date: Nov 2006 Location: South Bay Motorcycles: Honda ST1100 ABS (tweaked here and there) Name:	I think at this point it would be advised if someone else more familiar with your bike would ride it and give their opinion. Things just aren't adding up. __________________ It's not the answer that enlightens, but the question. - Eugene Ionesco Let us not pray to be sheltered from dangers but to be fearless when facing them. - Rabindranath Tagore A mind all logic is like a knife all blade. It makes the hand bleed that uses it. - Rabindranath Tagore

09-24-2020, 07:30 AM	#4
infecto Rookie Join Date: Aug 2019 Location: Oakland Motorcycles: Versys 1000 Ninja ZX-6r Name:	So i did get around to changing the oil and no change. Going to try changing the hydraulic clutch oil now.

09-24-2020, 08:12 AM	#5
Dmitriy ㅅ Join Date: Nov 2007 Location: Santa Clara Motorcycles: '02 x2, '03- 640ADV '00 LC4E '00 SXC 400 Name: Dmitriy	So you can try changing the slave piston o-ring It's the same the the output shaft o-ring 0770250021 (25mm x 2mm) And reverse bleed the clutch system with a syringe Mushy feel would be that imo. (Those bikes are old enough that the specific o-ring wears out by now) Nothing in the operation of the clutch will be different between the gears as the shifting drum has no effect on the push rod and vice versa.

09-24-2020, 09:07 PM	#8
infecto Rookie Join Date: Aug 2019 Location: Oakland Motorcycles: Versys 1000 Ninja ZX-6r Name:	Agree on all accounts. My assumption would be that it should be a static feeling across all gears and across all speeds. I guess to further describe the feeling further. All other gears feelings more in line with my experience on different bikes. At speed when I get into 5th gear and let off the clutch it engages with the lever at around 50% out and then just stop moving. Making sure I am not mixing up terminology here. So by mushy what I am saying is the clutch is only going back out about 50% when I release it. No excessive metal shavings, there was some dark flakes which I assume might be clutch. From pictures I have seen from other oil changes it did not look too excessive and while I usually dont judge oil by the color as its not accurate...this had a viscosity that just looked awful so I am guessing its been a bit since it was last changed. I will do as described o-rings and I might also rip open the clutch cover and see what I see. Never had to touch a cluth or gone that far on maintenance before but will see what I can see.

09-25-2020, 06:32 PM	#11
motomania2007 TC/MSF/CMSP/ Instructor Join Date: May 2008 Location: Merced, CA Motorcycles: BMW R1200R, FZ09, FZR400, CR250R Name: George	Has me thinking that possibly due to 5th being very tall would change engine dynamics __________________ If you are not having fun riding a motorcycle, you are doing it wrong. The best performance upgrade is upgrading the operating system of the operator. It is cheap, easy, fast, safe and works on every bike you will ever ride. I am also a Patent Attorney so if I can help you with any IP matters, please just ask.

09-26-2020, 03:16 PM	#12
infecto Rookie Join Date: Aug 2019 Location: Oakland Motorcycles: Versys 1000 Ninja ZX-6r Name:	If anyone would be gracious enough to test ride it I am down hah. I was playing around with it more, it does seem to be a engine dynamic. I dont notice it in 5th gear low speed. Only highway speeds in 5th gear. Edit: Did not notice any burnt smells, even compared to some other used oil. Last edited by infecto; 09-26-2020 at 03:21 PM..

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