Hey guys I have a general rear mount question: does it affect the longevity and functionality of the rear mount if the bike has lower rear shocks? My bike came with 1 inch lower rear shocks, and I'm wondering if that extra tilt is making my rear mount go bad.

 

Thanks crusader1xxx. About to install a new stock rear mount, and since I only seem to get about one year out of them, that 6 month time frame should work out fine.

 

Okay... Ride Report! Part One, and Part Two...

I did get out after work last night for a little, but unfortunately it was already dark and starting to get chilly by the time I was home and changed. My first ride was a fifteen mile loop that only had a brief twisty bit but had room for some acceleration, a variety of speeds, and some crummy pavement in a couple of construction zones. My first impression wasn't particularly positive. Overall vibration wasn't as bad as it is at it's worst with the Predator, but with the Predator it's only really bad in a couple of very specific engine speeds and is very smooth at other speeds. With the KS, I felt it very consistently through the whole rev range. It was honestly pretty annoying. It also made me wonder how much of my vibration actually reaches me as a result of the front mount, as opposed to the solid top link I run and the Sputhe stabilizer on my rear mount. More concerning than the vibration was the presence of some goofy handling. The first time I went over bad pavement, the bike weaved around unexpectedly in a very disconcerting manner. I started looking for bumps to hit, and tried some rapid weaving at a quick pace. I could completely feel the presence of "rear steer" going on, and I really didn't like it. On my way home I came to the conclusion that there's no substitute for a front stabilizer if you want really stable handling from a Dyna. I also thought that I would consider adding a stabilizer and keeping the KS mount if it was really smooth, but it wasn't. As I pulled into my driveway, I thought "Oh well, back to the Predator for me!" But being in a mood to tinker, I ended up not giving up so quickly...

After putting the bike back into my "front mount status (half on my Sears jack, scissor jack under the engine)," I added the second front shim that shipped with the mount. I then took extra care to make sure the pair of bolts across the top of the mount were completely loose while tightening the two lower bolts through the front of the frame. I followed this sequence the first time, but maybe my "hand tight" was still too tight on the top bolts. If the top bolts are too tight first, the center block on the mount may not center itself properly, and the whole nose of the engine may actually end up slightly off center. I also loosened all of my exhaust bolts (flanges and rear mount), and tightened them with the engine running. This process has reduced vibration for me in the past. My second ride was short, as it was getting cold, it was deer time, and the thought of dinner and beer was looming large in my mind. Also, I didn't really expect much difference, I just wanted to do my due diligence before abandoning this mount. After all, Crusader had to tinker with his a little before he was happy with the result.

WHAT A DIFFERENCE!!! My second ride was totally different from the first. There was a NOTICEABLE reduction in vibration across the whole rev range as compared to the Predator. I didn't have a chance to actually push the bike in corners at all, but the construction test was a night and day difference from the first run. The bike felt stable and planted over bad pavement, tar snakes and potholes. I think the KS mount is just very sensitive to correct installation and alignment. This is probably true with all of our front mounts, but maybe the increased lateral stiffness magnifies it with this piece. I don't yet know whether it'll truly pass a more demanding handling test, but based on this short ride I would say it's absolutely fine for those who aren't peg scrapers or really fast highway riders. And it might be fine for those situations as well (I hope), I just can't yet say. But it really was an improvement in comfort for sure!

Hopefully I won't have to wait for spring to answer the rest of my questions. But the OEM-style layout of this mount should allow for a stabilizer if it's really needed (the one from Alloy Arts looks like it would work with this mount), which I would consider if it really proves to be significantly more comfortable with handling "in the ballpark." But it really may be fine as is... I just couldn't tell from my short late-night ride.

But I can definitely say this: Kinetic Structures have come up with a really interesting design, the materials are high quality, it's well constructed, and it fits properly. I'm very encouraged by the results so far. But it is finicky... I was shocked at the difference between my first and second rides. My guess is that the second shim helped with vibration, and my more careful aligning/tightening sequence made a big difference in handling.

If I find a chance to wring it out properly before winter, I'll give a further update...

 

Very interesting and encouraging.

Thanks so much for your time and effort, both on the bike and on the keyboard.

 

I might have to try this mount. I was thinking of going with the chopper Haus, or predator originally. So many mounts to choose from and so many opinions.

 

Really want to try this mount. Considering leaving my front tru-track on as well.

 

No need to ever thank me for riding a motorcycle!

UPDATE:
Yesterday was a nice crisp fall day with temps in the low fifties. I got in about 75 miles. I stayed careful of cooler tires, unknown new front mount, lots of blowing leaves, but managed to hit some twisty stuff at a good pace. I also unexpectedly encountered two miles of recently torn up and grated pavement about to receive fresh blacktop. It was actually a pretty good test. My overall impression is that the KS mount feels similar overall to the Predator, but with a few subtle differences: It does a slightly better job isolating engine vibration, and it allows slightly more lateral movement in the whole drivetrain/swingarm assembly. From a handling standpoint, the biggest weakness seems to occur when hitting bumps while leaned over in a corner. I first noticed it setting up for a quick corner (40 mph two lane twisty road, cornering at about 65 mph). I moved my butt off the side of the seat just before turning in, and hit a bump just as I dipped into the corner. It's a corner I know well and can take faster without drama, but the bump definitely caused the rear tire to roll over slightly which changed my direction a little. Not enough that I was "off course," but it got my attention. Really smooth corners felt okay if I kept my pace "spirited" but moderate. I felt the rear-steer effect a couple more times on bumpy corners. I really don't mean to imply dangerous handling, it's WAY better than an unstabilized OEM mount. But I really didn't feel good on the torn-up stretch of road. There were constant wavy grooves, some quite deep. My front end felt solid, but I could feel the rear tire follow stuff around a bit which was disconcerting. I'm not sure how much more time there is this season to mess with things, but I'm not ready to give up on the mount. It's possible that I can still improve things with some adjustment. For example, the upper front mount bracket (not used with the Predator) has quite a bit of play before bolting it down to the cases. I have no idea whether it's in the optimum location now. Unfortunately I can't really leave it loose while the engine "settles in" because the oil filter interferes enough to prevent access to the bolts. I like the idea of this mount enough to try some further fine tuning... I'm being critical because I tend to evaluate everything by focusing on the downsides first. It doesn't mean I don't like it!

Using my made up scale below, I would say (based on how the mount is currently performing on my bike), that handling is absolutely fine (and improved from OEM) up until 5/10s. It's still okay at 6/10s, but you start becoming aware of some instability at the back sometimes. At 7/10s, the Predator wins (so far). 8/10s I only rarely find on the street (and haven't with the KS mount), and only when riding with my very skilled friends with actual fast bikes a few times a year.

Based on a blend of rider/bike ability
(Can be maxed out by any bike/rider combo. 10/10s means that combo couldn't push any harder)

1/10 - 3/10s
Normal putting around on a "cruiser"

4/10s
Picking up the pace...

5/10s
Using more of the sidewall, feeling aggressive. Pretty spirited riding

6/10s
"Chicken Strips" are getting smaller, body position is important

7/10s
Basically as fast as anyone should be going on the street

8/10s
Pushing the bike and the rider's ability really hard... Not to be taken lightly!

9/10 - 10/10s
TRACK ONLY!

If I can't nail down stability a bit more, I'll either go back to the Predator or try adding a stabilizer. Not sure yet. But the KS mount does a nice job with vibration control, and is definitely more stable laterally than the stock mount. Which is a nice combo overall. And it was a very nice fall day yesterday!

 

Very excellent report/review.

As it stands, it sounds like I'll be sticking with my current setup but I'm willing to reevaluate at any time.

I bet a Sputhe up front (with the KS) would be nearly a game changer. I just can't stomach the look of the front linkages on my current ride.

Ultimately, I'm really only looking to reduce the harmonic around 2500 that the Predator seems to have caused. The stability is intoxicating. I still think the isolator component in the Predator can be changed but I haven't torn it down to try and identify that part. It seems to be a standard industrial machine donut isolator....of which there are many options for differing amplitudes and frequencies...

 

It wouldn't surprise me that the wire mesh system doesn't adequately address the side to side stiffness required of the front motor mount. Here is an idea to address side play. The mount itself does not do too well for vibe isolation tho.

 

Very interesting idea! Kinetic's claim that different spring rates are used got me wondering along similar lines (solid mounts laterally, rubber mounted vertically). But my idea was basically a stock-stye setup, but the side plates have radiused grooves that the center block rides in, with rubber above and below. Yours looks like it makes more sense, though!