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#1 |
Join Date: May 2023
Location: AZ
Posts: 4
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Judder engaging clutch from takeoff - sources? Lifan X-Pect
Hi All,
I caught the bug 6 months ago and first picked up a Hawk DLX for myself. I was so impressed, I also picked up a Lifan X-Pect for my GF (the Hawk was perfect for me, but too tall/heavy for her, and the Xpect is just right for her). The Xpect has about 70 miles on it, and when I engage the clutch from a stop, I get a lot of clutch Judder. Happens no matter if its hot or cold. There is no judder when clutch is fully disengaged or fully engaged - only when slipping it primarily from a stand-still. In my mind that rules out things like dragging brakes, chain with tight-spots, etc (I also checked these separately). Its probably been doing this since I uncrated it, but I don't recall. I tried a few clutch adjustments and interestingly when I adjusted the clutch to be too tight (drags just barely when disengaged), the judder goes away. This lead me to believe the cause was warped frictions/springs. FWIW I am running Rotella T4 15W-40, and we primarily ride on acres of our property which is mostly dirt and some paved roads. I suspected it was just bad clutch frictions/steels, and got a full replacement clutch (steels, frictions, springs, basket, etc) from the place I bought the bike from. Figured I would just do a quick swap and not waste a lot of time Sherlock'ing it. I swapped the clutch out, readjusted, and it did not improve the judder at all. So I'm a little befuddled. Did I get another set of bad parts, or is something else causing the judder? Looking at the Lifan diagram, the only clutch parts that were not replaced are #1 clutch lifter, #2 clutch pusher, #3 bearing, and #11 thrust washer. I'm somewhat suspicious of the bearing, pushrods, and pushrod bore. I bought a new brand-name 16003 bearing to try, and will measure and inspect the rest of the parts. I plan to dig into it again soon, and this time will be taking a lot of runout measurements on all the components, put the frictions/steels on a granite plate and check with feeler gauge, etc. But before I get that far I wanted to get some input on what else could cause this, in case I'm completely overlooking something else that could be contributing? |
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#2 |
Join Date: Sep 2014
Posts: 1,911
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Loose engine mount bolts will do that.
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#3 |
Join Date: Dec 2021
Location: Missoula MT
Posts: 37
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For what it's worth, this is my 2nd summer with a new X-pect and while it does not have a judder at takeoff, it often has a kind of rusty sounding squeak if I take off a bit aggressively, especially in the morning when I'm first getting going. Doesn't seem serious enough to bother with but I'm keeping an eye on it. I also run Rotella T4.
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#4 |
Join Date: May 2023
Location: AZ
Posts: 4
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Good suggestion - I checked those also, and they were tight
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#5 |
Join Date: May 2023
Location: AZ
Posts: 4
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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:
After all this, the clutch is silky smooth and we are very happy with this little machine! ![]() Last edited by bugman-74; 04-23-2024 at 11:05 PM. Reason: add link |
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#6 |
Join Date: Jan 2024
Location: East Coast NC
Posts: 27
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just for laughs,, did you at anytime before checking the clutch plates out change oil?? you got new stuff from lifan but was that using same oil.. do you remember what you were using before the change to the valvoline you show in post??
![]() maybe you used these frictions.. https://www.whygostock.com/ebc-upgra...t4-7-clutches/
__________________
MX racer in the 80's. Now fulltime RVer looking to get back on two wheels. |
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#7 | |
Join Date: May 2023
Location: AZ
Posts: 4
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Quote:
These are the frictions I used: https://www.whygostock.com/clutch-fo...c-250cc-lifan/ |
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Tags |
clutch, judder |
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