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Finally got to install and take a ride with the Kinetic Structures front engine mount. To refresh the background I had previously been a fan of the Glide Pro Mount, and would still say that of the rubber/urethane/polymer (whatever) type of motor mounts, Glide Pro is my favorite. But even Glide Pro mounts eventually wear out. Mine would last about 3-4 years before needing replacement, which IMO is good service.

the Kinetic Structures unit installs the same as the others. Loose install with the bike upright and level, start the motor and let it run for a few, then tighten everything. I did need to come up with the 3/8” center bolt set previously discussed. The engine bounces less at idle with the KS mount and riding reveals the same minimum vibration as the Glide Pro unit produced. Only a bit of buzz in the foot pegs and nearly none in the handlebars. I would say the KS unit raises the bar over any of the soft compound units with longevity the remaining question. But the KS units should last longer and are easily rebuildable for $50 as opposed to buying an entire mount, so that’s an advantage.

Overall I’m pleased and would recommend.
 

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Thanks for the review, Festus. I'll keep them in mind when my original fails....again.
 

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When I realized it was to buy another front motor mount for my '85 FXRS I did a little research and sort of stumbled on this one:
I spoke to the engineer at Kinetic Structures several times about the technology and non-motorcycle applications they had been building these for and decided to take a chance and put one on The "Moonraker". Love it. I've only run it 5,000 mi or so and can't speak to longevity. At this time...I'm very satisfied. There are cheaper options, but then they are..well, cheaper.
This Kinetic Structures motor mount is flawed. I have tried it and found the best option was the latest revision factory front motor mount. True Track and Sputhe will also tell you the same thing...

The Kinetic Structures motor mount is 1/8" taller than a broken in factory mount when measured from the top of the frame cross member to the bottom of the engine mount. In conversation with Harry at Kinetic Structures he stated that at 200 lbs of load (assumed load on front motor mount at rest) the Kinetic Structures mount I returned compressed just as much as a factory Rev D motor mount. I asked him if this rubber motor mount had been "broken in" at all and he said no. My factory Rev D motor mount settled almost an 1/8" in the first 250 miles and none after.

Second issue is that there is a gap between the snubber washer and stainless steel cushion underneath the cross member. That literally means that if you are strong enough, you can pick up your motor in the frame about an 1/8" before the snubber washer hits the stainless steel cushion for "damping". I don't know what engineer thought that was a good idea, but sounds like a terrible scenario under power. The stabilizer links move in an arc, the larger this swing is the more wiggle drive train wiggle there is in the frame.
 

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I went with the Alloy Art front mount have been very happy with it. It's urethane but not super stiff at all. Liked it right after install still flawless 3years later no sign of wear. The 124" motor is jumpy by nature as well. It's gonna be my go to mount from here out.
 

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LumberjackLloyd,
That's all interesting information. Thanks for posting. What are the ramifications of running the flawed KS mount then..?
Mine's been on the bike just over a year, and 12,000 mi. and I'm still real pleased.
I run a lot of Interstate miles on this bike. Typically cruising 75-90 mph and enjoy the smoothness of the FXR ride above all else. If there's a better way to maintain that ride, I'm all for it.
How is the Rev D mount identified..?? Special part number..??
Thanks again.
 

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Hmmmm. It’s been a long time since I tried a stick front mount, with the reason being that the last one I bought from HD was so hard that it like the motor was bolted directly to the frame—bike shook like crazy. I don’t know what Rev. it was.

the KS mount starts out taller than the others, requiring new to raise the motor in the frame a bit more for mounting, but then compressed to its neutral position when the motor is lowered. I didn’t measure before and after, the “before” being on a collapsed GlidePro Mount, anyway. the motor seems to be in its proper position. I figured the difference was in the different material used in the KS versus the elastomer damping material. I see no problem.

I followed the mounting instructions and my snubber washer on the underneath of the cross member is snug against the bottom of the mount. No free play to allow the engine to lift. I can’t imagine the tiny amount of up/down movement resulting in enough of an arc on the end of the stabilizing link to be a factor.

Not trying to argue or justify. All I know is that my motor visually moves less with the KS mount than any of the elastomer/rubber ones before it. Maybe the latest Revision of the factory part is better than previous models. Whatever works for whoever. Me, I’ll be interested to see how the KS part holds up over time. That will be the true test.
264732
 

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Guido: how does the gap between upper and lower on your KS mount compare with mine? This is about 1/4”.
 

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The Rev D part number is 16207-79D. That mount has been used since 79 and been revised due to oil deterioration issues and engines that make more power. The current revision does not deteriorate from oil like the past revisions. Yes, it is stiffer than the OEM engine mount from the 90's; it should be. If you feel it vibrates too much hop back on your ridged shovel or evo...that's vibration!

With the Kinetic Structures mount the 250lb rotating mass is sitting 0.125" higher in the frame which would adversely effect how light or nimble the bike feels. The engine was so much higher in the frame that my Bassani RR3 started to hit the footpeg! Again, fitment and height of the Kinetic Structures mount was confirmed with Harry to be correct.

I could feel the walking in the rear end when rolling on the throttle at speed due to the extra play in the front motor mount...Yes, alignment was checked with strings.
 

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Guido: your mount has been in place for 1 year and 12,000 miles and has apparently settled about .05 inch lower than mine. I’ve only just installed and ridden mine so it makes sense that a bit of settling would occur with use from new. It will be interesting to see if my mount settles about the same as yours.

Lumberjack: I don’t have the issues with my KS mount that you describe so I can’t comment. Ride safe.
 

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For me...The open question about KS front mounts is longevity. I'm not able to identify any sort of "walking in the rear end" as described by LumberjackLloyd. Doesn't mean it's not happening but perhaps I'm not sufficiently experienced or educated on handling issues to recognize it. I bought my '85 FXRS brand new in 1985 and have just crossed 300,000 mi on her. I'm the first one to admit, I'm not a "hi-performance" rider. About the most exotic handling I do is changing lanes. I don't "run the twisties" and places like the Tail of the Dragon are on my "avoid" list. (As an aside...I used to live in that region of the country and those mountain roads were simply a P.I.A. to me, but to each their own). For the time being I'm quite pleased, but will be watching for "Settling" to see if it becomes an issue. Occasionally checking the torque on the centerbolt might not be a bad idea...and I'll track how long before I might need a replacement for the mesh.
 

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Guido. I’m in the western NC mountains a lot and I do ride tight switchbacks as well as rolling, more gentle sweeping turns in the foothills and as you say, I’ve never had any weird handling issues switching from one mount to the next. Agree that the longevity issue will now be key, as the rebuildable factor of this mount is unique to the others. I was a fan of Glide Pro but if these last longer and are cheaper to rebuild then they’ll have the edge. We shall see.
 

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The Rev D part number is 16207-79D. That mount has been used since 79 and been revised due to oil deterioration issues and engines that make more power. The current revision does not deteriorate from oil like the past revisions. Yes, it is stiffer than the OEM engine mount from the 90's; it should be. If you feel it vibrates too much hop back on your ridged shovel or evo...that's vibration!

With the Kinetic Structures mount the 250lb rotating mass is sitting 0.125" higher in the frame which would adversely effect how light or nimble the bike feels. The engine was so much higher in the frame that my Bassani RR3 started to hit the footpeg! Again, fitment and height of the Kinetic Structures mount was confirmed with Harry to be correct.

I could feel the walking in the rear end when rolling on the throttle at speed due to the extra play in the front motor mount...Yes, alignment was checked with strings.
Wouldn't the front and top engine stabilizer prevent the front of motor from moving side to side? If you feel tracking or rear walking issues and movement I'd be looking at the swing arm area first
 

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Wouldn't the front and top engine stabilizer prevent the front of motor from moving side to side? If you feel tracking or rear walking issues and movement I'd be looking at the swing arm area first
As the engines moves up and down, it moves in an arc because of the stabilizer links.
 

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Technicaly yes but damn, how much is your motor moving? Would have to be 2" up and down at least to even make over an eighth inch side movement...
 

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Technicaly yes but damn, how much is your motor moving? Would have to be 2" up and down at least to even make over an eighth inch side movement...
You turn the front wheel way less than an eighth when you're at cruising speeds and making a turn...power out of that turn with excess free play in a motor mount and you'll have the Dyna wiggles in a hurry.
 
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