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Change to 2017 Rear Motor Mount?

Messages
475
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227
Location
Dublin, OH
#1
Although I never experienced the terrible wheel hop and engine hitting the firewall often talked about here as a reason to change the rmm, I installed a cp-e mount and at least for me, the nvh penalty was too great. It really was a dramatic difference in noise and vibration, so I put my stock rmm back in. But here is something I noticed--C J Pony Parts has lots of installation videos on YouTube, as does Boomba and others. These are a great help no matter what brand part you are installing. Before doing my rmm, I watched the video on installing a Cobb rmm, and near the start of the video the guy had the OEM mount that came out of the car in his hands, and he could easily deflect the large side rubber mounted bushing just using his hands. There was a ton of flex in the stock rmm. In contrast, when I pulled out my stock rmm, it was hard to move the bushing in the rubber at all. You can get a little movement, but not much. It makes me think that maybe Ford stiffened thing up a bit, at least on the 2017s, and maybe that is why I am not feeling all the issues with the stock mount.
 


Messages
155
Likes
53
Location
Ravenna
#2
Interesting to hear about the cp-e being too much. I’ve had mine for over 10k miles and it only slightly vibrates if I do a lazy take off. There is however a thread somewhere about all of the model year parts changes. I believe a lot was changed for 16+ suspension and mounts.
 


XR650R

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Premium Account
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3,022
Location
Eerie
#3
My '17 hasn't clunked like so many report, either. That said, I don't dump the clutch or shift it real hard. I guess the only way to know would be to compare a new one to an older one.
 


alexrex20

1000 Post Club
Messages
1,472
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611
Location
Spring
#5
My 17 clunked hard on the 1-2 shift and wheel hopped bad on a launch. Not anymore with my AWR mount. Y'all ain't shifting hard enough.
 


Last edited:

green_henry

1000 Post Club
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757
Location
Pleasant Hill, CA
#6
The OEM mount on my 17 was very easy to flex by hand; it's rubber, so it's probably going to be more flexible in warmer weather. I replaced it within a few weeks of buying the car with a Mountune RMM and am very happy with it.
 


Messages
166
Likes
32
Location
asdfsafd
#7
Mountune mount is great in my 2017. Definitely an improvement. Can't say the engine hit the firewall before but the wheel hop was significant.
 


TDavis

1000 Post Club
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1,435
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1,149
Location
Columbia
#8
I can attest to the 2017 mount being easy to flex by hand when my friend replaced his with a Cobb. I plan to go the AWR route
 


Messages
73
Likes
33
Location
Atlanta
#10
I too am puzzled by all the discussion of the rear motor mount. My 17 does not seem to do any of those bad things, at least not enough to be concerned about. The times when I have experienced mild wheel hop seem to be related to surface irregularities. The same kind of thing happens with motorcycles. I live in the south so our streets are not that rough. Maybe I would think otherwise if I lived in a colder climate.
 


Messages
417
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542
Location
Okemos
#12
How long did you have the mount in for? After break-in the NVH's reduce. Assuming it was an initial impression, put the mount back in and drive it until it's fully broken in.
 


Messages
181
Likes
69
Location
North Branford
#13
My 17' didn't seem as bad as what others had said about the earlier cars, but there was a noticeable drivetrain slop. I replaced it with a mountune mount when the car had a few hundred miles. NVH increase was negligible. I can shift pretty aggressively now and get no clunking or knocking.
 


XR650R

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3,022
Location
Eerie
#14
My 17' didn't seem as bad as what others had said about the earlier cars, but there was a noticeable drivetrain slop. I replaced it with a mountune mount when the car had a few hundred miles. NVH increase was negligible. I can shift pretty aggressively now and get no clunking or knocking.
Mine wasn't bad when new, but at 11,000, it was sloppy. I had to shift carefully when getting on it.

Put the mountune on this morning, and instant difference. NVH was negligible, as you said, and it will get smoother. A louder exhaust would cause more vibes than this piece does. Move at any rpm higher than idle, and it's not noticeable at all. It shifts like a more expensive car. Solid engagement, and the sloppiness is gone. Seems to help with the torque steer, too.
 


Messages
59
Likes
35
Location
Huntington Beach
#15
Sorry for reviving this old thread. I have a late 2018 build and still has the stock RMM and I have never had a clunk or severe wheel hop like I did on my 2016 build. And yes I have shifted hard enough to chirp tires, but no engine craziness. Currently on 205/45/17 Michelin PSS (BMW star spec) so it has plenty of grip to work the rmm. I get no wheel spin on the Dizzy “stage 2” 91 tune in any gear. (Actually haven’t tested reverse lol) just wanted there to be more info added for when people fine this thread later.
 


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