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Vibration on takeoff and clunking noise while shifting

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Gilmer
#1
Hey all. So, recently, I noticed this clunking "pop" while I'm shifting gears. It occurs mostly in the lower gears, up to 4th. It happens more often when the AC is pulling. My suspicion is leading me to believe that it's a mount, and I haven't had time to pop the hood to see what shape the mounts are in.

It's also vibrating on takeoff, as soon as I'm releasing the clutch and giving it gas. I'm hoping that's related to the mount issue.

Thoughts?
 


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texangal75
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Thread Starter #2
I forgot to mention that it's a '14 with 139k, and also has the street spec RMM, as well as factory mounts.
 


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texangal75
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Thread Starter #4
Sounds like a mount, for sure.
That's exactly my what my suspicions are, but wanted to get thoughts on this. I've never had a mount fail on me before, so I'm trying to figure this out. My plans are to put my car in the shop in the next couple of weeks to get the techs where I work at to look at it, but in the meantime, I'm planning a 4 hour trip for a meet next weekend so I was anxious about putting it on the road.
 


XR650R

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#6
That's exactly my what my suspicions are, but wanted to get thoughts on this. I've never had a mount fail on me before, so I'm trying to figure this out. My plans are to put my car in the shop in the next couple of weeks to get the techs where I work at to look at it, but in the meantime, I'm planning a 4 hour trip for a meet next weekend so I was anxious about putting it on the road.
It's 7 years old w/140,000. Motor mounts are a wear item. They get hot, cold, wet, dry and eventually stop doing their job so well.
I'd take a look at all the bushings in the suspension, etc., too, just to be on the safe side. Don't let them sell you stuff you don't need.
 


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#7
It's hard to say how your particular "pop" sounds like without a recording but... I previously had popping/clunking and intermittent clutch shudder right at the top of the release, so I replaced all 3 mounts. Things quieted down somewhat but didn't get completely fixed, including the shudder.

It did go away, however, when I replaced clutch/flywheel at ~60k miles. The flywheel had pronounced slop in the springs and had some hot spots and maybe that contributed to it. It's difficult to say tho, because in the process of figuring out the issue, the dealership also replaced the mounts again, so could be combination of burned flywheel and motor mounts.

In retrospect, it was more annoying than anything, so I wouldn't worry your trip. I drove for a bit today and I get more pronounced clutch clunking with AC even now, with less than a year-old mounts/clutch/flywheel.
 


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texangal75
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Thread Starter #8
Sounds like a mount for sure. I’d check first that the RMM is secured and nothing loosened up, then the passenger side engine mount. Can’t recommend a power flex insert for it highly enough.
Exactly what I was hoping. I'm putting it in my shop at work in a couple of weeks, but have a trip in taking in it next weekend. It runs just fine, no gear issues. Thank you so much for your input.
 


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texangal75
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Thread Starter #9
It's hard to say how your particular "pop" sounds like without a recording but... I previously had popping/clunking and intermittent clutch shudder right at the top of the release, so I replaced all 3 mounts. Things quieted down somewhat but didn't get completely fixed, including the shudder.

It did go away, however, when I replaced clutch/flywheel at ~60k miles. The flywheel had pronounced slop in the springs and had some hot spots and maybe that contributed to it. It's difficult to say tho, because in the process of figuring out the issue, the dealership also replaced the mounts again, so could be combination of burned flywheel and motor mounts.

In retrospect, it was more annoying than anything, so I wouldn't worry your trip. I drove for a bit today and I get more pronounced clutch clunking with AC even now, with less than a year-old mounts/clutch/flywheel.
Thank you so much for your input, and many thanks for putting my mind at ease. I daily it, so I've grown accustomed to the clunk, and like you say, it's rather annoying. The clutch is fine, still shifts smoothly and no issues with it going in gear, so that's a relief.
 


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texangal75
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Thread Starter #10
It's 7 years old w/140,000. Motor mounts are a wear item. They get hot, cold, wet, dry and eventually stop doing their job so well.
I'd take a look at all the bushings in the suspension, etc., too, just to be on the safe side. Don't let them sell you stuff you don't need.
Exactly why I'm putting it in the shop where I work at. They already know how I am with my car, and my adviser won't upset me anything since I'm planning on getting the inserts to have them install.

My suspension seems to be ok as I'm still on stock springs and have Koni orange struts and shocks. The Koni's have approximately 20k on them now.

Thank you so much for your input.
 


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texangal75
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Thread Starter #11
An update: after it violently popped on me last Thursday shifting from 1st to 2nd, I asked the techs and service adviser at my job to put it on the rack, and the tech discovered my RMM had disintegrated. Replacement bushings arrived today.
 


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#12
An update: after it violently popped on me last Thursday shifting from 1st to 2nd, I asked the techs and service adviser at my job to put it on the rack, and the tech discovered my RMM had disintegrated. Replacement bushings arrived today.
That's pretty spectacular. I guess that's one downside of poly bushings over rubber OEM ones...
 


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texangal75
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Thread Starter #13
That's pretty spectacular. I guess that's one downside of poly bushings over rubber OEM ones...
Exactly. I went back OEM for a while. Not sure when I'm going back to the aftermarket.
 




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