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Discussion Starter #1
So after riding on the 3rd day out in the Black Hills last week the wife tells me the reason she doesnt like going over 30 on the paved roads (which we try to avoid but sometimes needed to reach another trail) is it starts to shake. Kinda wish she would have told me the first day... Unfortunately I didn't have much time to test it out, but here is what happens.

Driving at 15 mph things feel fine, no noticeable shake accelerate hard to 40 and you just start to feel shake but as soon as you let off the throttle and weight transfers down on the front the wobble is very noticeable. its pretty unsettling between 35-40 mph, I didnt try faster to see if it gets worse. As you slow down from 35 to 30 it lessens and really isnt noticeable at 25 mph.

Not sure what to think at the moment, I put the dial indicator on both inside of each front rims and outside and I have roughly 0.022" of runout on the right front wheel and 0.027" runout on the left front wheel when mounted and spun by hand on the axle. 25 thousandths of an inch shouldnt cause this.

Thoughts?
 

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Discussion Starter #3
The Kodiak only has about 300 miles on it, the part that sucks is I have to drive 2 hours just to test it out (legally) .
 

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So after riding on the 3rd day out in the Black Hills last week the wife tells me the reason she doesnt like going over 30 on the paved roads (which we try to avoid but sometimes needed to reach another trail) is it starts to shake. Kinda wish she would have told me the first day... Unfortunately I didn't have much time to test it out, but here is what happens.

Driving at 15 mph things feel fine, no noticeable shake accelerate hard to 40 and you just start to feel shake but as soon as you let off the throttle and weight transfers down on the front the wobble is very noticeable. its pretty unsettling between 35-40 mph, I didnt try faster to see if it gets worse. As you slow down from 35 to 30 it lessens and really isnt noticeable at 25 mph.

Not sure what to think at the moment, I put the dial indicator on both inside of each front rims and outside and I have roughly 0.022" of runout on the right front wheel and 0.027" runout on the left front wheel when mounted and spun by hand on the axle. 25 thousandths of an inch shouldnt cause this.

Thoughts?
I had this with my 2018 kodiak, mine turned out to be the big huge lug chinese knock off slingshot tires i had installed on the bike the day i bought it.
in my research befor i discovered the cause, i found a few possible reasons...
air pressure, tires not completely seated, bent a arm, alignment can be off from factory, out of round tire and or rim, wheel bearing.

theres a few things to check, I wish you luck.
 

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Possibly out of balance?
 

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A bad wheel bearing can do this, and it doesn't take many miles but can happen with the right kind of hit on a rock. I slid down a steep rock and hit the right front first and popped the bearing. Then with the wheel on could not detect the problem by feel or sight. I took the axle nut off and bearing part feel on the floor.
And another thing that can cause this is low air pressure. I use 26" O.G.s' on stock wheels and the sidewalls flex with low p.s.i. I run 11#s and the side ways shake goes away. The tread follows the smallest ridge or imperfection while the wheel wants to go straight.
 

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A bad wheel bearing can do this, and it doesn't take many miles but can happen with the right kind of hit on a rock. I slid down a steep rock and hit the right front first and popped the bearing. Then with the wheel on could not detect the problem by feel or sight. I took the axle nut off and bearing part feel on the floor.
And another thing that can cause this is low air pressure. I use 26" O.G.s' on stock wheels and the sidewalls flex with low p.s.i. I run 11#s and the side ways shake goes away. The tread follows the smallest ridge or imperfection while the wheel wants to go straight.

I hit a rock "hard" once, it was sticking out of the side of a rut that I slid into at ~15 mph, about threw me off, bent lower a-arm, pinched frame slightly at a-arm mounting bracket, bent rim bead, small 1" cut on tire sidewall, and bent the steering joint. Figured the bearing was toast but was amazed the bearing was okay but the solid steel splined steering joint had twisted.
 

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It's a good thing we don't break a bearing every time we hit a rock, I was telling the O.P.er that if something like a 'wobble/shake' develops, what to check.
I was surprised at how the slow slide and angle I hit the rock at broke the bearing. I was going slow, maybe the slowest I had gone that day.
And as for the tire pressure, there is not problem running high pressures and if you don't like it you just let the air down.
 

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Discussion Starter #9
Possible I might have had excessive toe-in, did some adjustments, kinda hard to measure but I think I have about 2 degrees toe-out now and it feels a little better, but I could only test it up to about 25mph. I need to put it on the trailer and go about an hour south of here to try to find a place to test it out and see if the adjustments help.
 

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Most of the time a shake or vibration that comes and goes with speed is a result of a balance issue. My tires did the exact same thing you described at the same speeds and I took them and had them balanced. It helped a lot and my shake moved up till it didn't start till about 45 which is faster than I need to go anyway. If you do get em balanced make sure they use the sticky weights on the inside of the rim so they don't knocked off as easy.
 

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It's a good thing we don't break a bearing every time we hit a rock, I was telling the O.P.er that if something like a 'wobble/shake' develops, what to check.
I was surprised at how the slow slide and angle I hit the rock at broke the bearing. I was going slow, maybe the slowest I had gone that day.
And as for the tire pressure, there is not problem running high pressures and if you don't like it you just let the air down.

Definitely good advise, on the flip side of my rock hit story I recently changed out a bad rear bearing on a friends 2008 Kawaski Brute Force and it came out in pieces. Less than 3K miles on machine and he really babys it when we ride. He also only weighs about 140 lbs.
The remnants of the bearing didn't have any manufacture or part number on it, but was the original OEM bearing. Probably not a Koyo bearing but who knows.
 

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Possible I might have had excessive toe-in, did some adjustments, kinda hard to measure but I think I have about 2 degrees toe-out now and it feels a little better, but I could only test it up to about 25mph. I need to put it on the trailer and go about an hour south of here to try to find a place to test it out and see if the adjustments help.
Grizzlies come with a slight toe-out which makes steering more forgiving for the novice rider. i wrenched mine back to straight as possible and like it. It took a few corners to understand how the wrench changes changed the steering feel. If you find one wheel with a changed toe look, it is probably a bad bearing. The first time a bearing failed for me I noticed a different toe look so, tried adjusting the tie rod end which did not help. Then as I was riding to find the problem, the bad bearing caused the rotor to run at an angel against the pad and the brake got very hot and there was brake fade. I installed a new bearing, set the tie-rods back and the brakes stopped getting hot.
The benefit to this problem was I played with the toe to learn I like the front wheels running straight ahead. I ride on pavement sometimes between trail heads for several miles and I don't have excessive tire wear like others do with stock alignment.
 

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Possible I might have had excessive toe-in, did some adjustments, kinda hard to measure but I think I have about 2 degrees toe-out now and it feels a little better, but I could only test it up to about 25mph. I need to put it on the trailer and go about an hour south of here to try to find a place to test it out and see if the adjustments help.

I set mine to (no-toe straight/parallel) no problems at all, and maybe slightly better fuel mileage.
 

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I set mine to (no-toe straight/parallel) no problems at all, and maybe slightly better fuel mileage.
You can also see there is less dust rising from the front tires on dirt roads. I started noticing the amount of dust off other machines, then had a buddy ride mine with me following on his. I straightened out the front end and rode his again and could see the difference. Toed-out there is a scuffing that goes away running straight ahead.
 

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Hey Savage...The Kodi toe-in spec is .0-.39" or 0mm-10mm. I run my machines at zero for better cornering. At zero or slight toe out the steer will wander but not really wooble or shake. More toe out than that could cause so issue.

I would closely inspect the tie rod ends for defect or been loose especially the inner connections.

Some other thoughts..

Check the brakes if one is binding for some reason the EPS will compensate causing a wobble feeling.

Do you have the machine in 4wd when this happens. I feel the wooble trail riding in 4wd on the 2016 manual Kodi's don't feel it with my 2019.

I ran reptiles for a while the ran smooth without wobble or shake. Maybe put your Growlers on her machine to see if the tires/rims make a difference however don't let her ride it you won't get your tires back.
 

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I've had my 27" reptile radials on my Kodiak for 500 miles now, 2 of the 4 tires have a bit of a side to side wobble (maybe 1/4" if you watch them while driving straight) and it defiantly causes a wobble in the 30-35mph range on my Kodiak. Nothing I consider "unsettling" but you can feel it. Its one of very few complaints I found on the tires while researching, I may put 2-3oz of Airsoft BB's in each tire to see if it removes the wobble.
 

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Discussion Starter #17
Hey Savage...The Kodi toe-in spec is .0-.39" or 0mm-10mm. I run my machines at zero for better cornering. At zero or slight toe out the steer will wander but not really wooble or shake. More toe out than that could cause so issue.
Inspected the arms and steering linkage, it was all looking good and tight from the factory. no damage to the tie rods or any of that.

It was toed in quite a bit which also explains why it would feel a little squirrely at times, toed it out a few degrees and that wandered a bit. Now its sitting at 0deg toe with a rider on it, feels like the steering is right on.

The wobble lessened some but was still there.

Brakes feel good
 

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Discussion Starter #18
I've had my 27" reptile radials on my Kodiak for 500 miles now, 2 of the 4 tires have a bit of a side to side wobble (maybe 1/4" if you watch them while driving straight) and it defiantly causes a wobble in the 30-35mph range on my Kodiak. Nothing I consider "unsettling" but you can feel it. Its one of very few complaints I found on the tires while researching, I may put 2-3oz of Airsoft BB's in each tire to see if it removes the wobble.
The rears are good, but I suspect the front has a balancing issue and I also see about 1/4" side to side wobble in the tread as well. The wheels are nice and true so its either the bead isnt quite perfect or the tire mold is a little wonky.

I put her factory fronts on and no wobble what so ever so its definitely something with the tire.
Luckily I kept her stock wheels and tires for backup in case something where to go wrong on either of our ATV's.
 

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Great to see a resolution to your thread! I had a feeling it was going to end in a balance problem but sometimes it doesn't hurt to check all the other variables just to have confidence in the rest.



No telling what might be causing the out of balance. Buddy of mine bought a new truck years ago and had them pull his big tires off his trade and install them on the new truck. It would jar your teeth at about 50 mph and he had it re-balanced maybe 6 times over several weeks, and they would find them all out of balance, again, every time. The dealership finally decided to pull off one of the tires and look at the inside of the tire, basically claiming that something was wrong with the tires. (they didn't wobble on his old truck though) Pulled a tire off the rim and it was full of water. Checked them all and all were full of water, well not full but maybe a gallon in each tire. The young kid that they had doing tires at the dealership had washed the tires "good" before installing them on the new truck rims and left water in them. This had gone on for like 6 months and a whole lot of frustration.
 
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