Judder engaging clutch from takeoff - sources? Lifan X-Pect

Mudflap · 05-14-2023, 05:58 AM

Loose engine mount bolts will do that.

bugman-74 · 05-14-2023, 05:56 PM

Quote:

Originally Posted by Mudflap

Loose engine mount bolts will do that.

Good suggestion - I checked those also, and they were tight

bugman-74 · 04-23-2024, 02:58 AM

Hi Fellas,
Well its been a year since I posted, but I did fix the clutch judder issue on my Lifan Xpect. So I wanted to follow up to my post in case anyone winds up with a similar issue. To recap: I had pretty severe clutch judder when engaging the clutch from a stop. I had previously gotten a full replacement Lifan clutch assembly (steels, frictions, springs, basket, etc) which I installed but made zero improvement.

I recently took everything back apart again, and inspected thoroughly. I checked thickness variation (micrometer) and flatness (granite inspection slab and feeler gauges) of the frictions, steels, checked runout of the clutch pushrod on v-blocks, and a few other critical interfaces. There was no “smoking gun” that I could find.

So I bought some new parts and changed a few things up, hoping something would make a difference. And long story short I have succeeded in fixing the issue 100%, although I can’t pinpoint exactly which part or parts solved the problem, so here is a rundown of everything I did:

I swapped the Lifan frictions for EBC frictions from whygostock (these: https://www.whygostock.com/clutch-fo...c-250cc-lifan/). I suspect they are #CK1119, but can’t confirm. The inside diameter of the EBC’s is larger (91mm versus Lifan which is 83.2mm), but they work just fine. See photo for side-by-side comparison. It is apparent to me that the construction might be a tad different based on comparing the friction material between the two (the EBC’s appear to have more cork).
I re-used the Lifan steels (they measured in spec).
I replaced the Lifan springs with EBC #CSK41.
Although the bearing felt fine, I went ahead and replaced it with a new old stock Koyo 16003. (Beware of counterfeit bearings!)
I lubricated the clutch cable with PJ1, and adjusted per the manual.
I normally run Rotella T4 15W-40, but opted to change it up this time and used Valvoline full synthetic motorcycle 10W-40 (it’s what my local auto parts store had on the shelf).
I also soaked the frictions for a full 24+ hours in the Valvoline.

After all this, the clutch is silky smooth and we are very happy with this little machine!

04-23-2024, 02:58 AM	#3
bugman-74 Join Date: May 2023 Location: AZ Posts: 4	Hi Fellas, Well its been a year since I posted, but I did fix the clutch judder issue on my Lifan Xpect. So I wanted to follow up to my post in case anyone winds up with a similar issue. To recap: I had pretty severe clutch judder when engaging the clutch from a stop. I had previously gotten a full replacement Lifan clutch assembly (steels, frictions, springs, basket, etc) which I installed but made zero improvement. I recently took everything back apart again, and inspected thoroughly. I checked thickness variation (micrometer) and flatness (granite inspection slab and feeler gauges) of the frictions, steels, checked runout of the clutch pushrod on v-blocks, and a few other critical interfaces. There was no “smoking gun” that I could find. So I bought some new parts and changed a few things up, hoping something would make a difference. And long story short I have succeeded in fixing the issue 100%, although I can’t pinpoint exactly which part or parts solved the problem, so here is a rundown of everything I did: I swapped the Lifan frictions for EBC frictions from whygostock (these: https://www.whygostock.com/clutch-fo...c-250cc-lifan/). I suspect they are #CK1119, but can’t confirm. The inside diameter of the EBC’s is larger (91mm versus Lifan which is 83.2mm), but they work just fine. See photo for side-by-side comparison. It is apparent to me that the construction might be a tad different based on comparing the friction material between the two (the EBC’s appear to have more cork). I re-used the Lifan steels (they measured in spec). I replaced the Lifan springs with EBC #CSK41. Although the bearing felt fine, I went ahead and replaced it with a new old stock Koyo 16003. (Beware of counterfeit bearings!) I lubricated the clutch cable with PJ1, and adjusted per the manual. I normally run Rotella T4 15W-40, but opted to change it up this time and used Valvoline full synthetic motorcycle 10W-40 (it’s what my local auto parts store had on the shelf). I also soaked the frictions for a full 24+ hours in the Valvoline. After all this, the clutch is silky smooth and we are very happy with this little machine! Attached Thumbnails Last edited by bugman-74; 04-23-2024 at 11:05 PM. Reason: add link
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05-14-2023, 05:58 AM	#1
Mudflap Join Date: Sep 2014 Posts: 1,871	Loose engine mount bolts will do that.
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