Bike Wobbles at 40+ MPH

Rezin · 06-26-2022, 09:54 PM

Quote:

Originally Posted by JerryHawk250

Are the front forks lowered in the right position in the triple tree?

Ha you got me on the forks. Not sure how to check for that.

BrokeAss · 06-26-2022, 10:58 PM

Loose steering stem bearings, loose front axle, loose rear axle, loose fork legs, out of balance or out of round wheel(s)...

Thumper · 06-27-2022, 06:47 AM

Quote:

Originally Posted by Rezin

Ha you got me on the forks. Not sure how to check for that.

Can you get the bike onto a lift, or a 5gallon can? With front wheel unweighted, you can push/pull on the forks from in front of the bike(one hand on each). You should be able to feel the movement if the front fork bearings are not cinched up enough. Just tighten the top of the steering stem bolt until the play is gone and test it. A helper to stabilize the thing while you do this would be useful.

You can check out the axel nuts and the swingarm bearings while it is off the ground too. Lift/drop from above (reaching around the seat with both arms and grabbing the tire at the top). It should not have any free play.

Rezin · 06-27-2022, 09:34 AM

Quote:

Originally Posted by Thumper

Can you get the bike onto a lift, or a 5gallon can? With front wheel unweighted, you can push/pull on the forks from in front of the bike(one hand on each). You should be able to feel the movement if the front fork bearings are not cinched up enough. Just tighten the top of the steering stem bolt until the play is gone and test it. A helper to stabilize the thing while you do this would be useful.

You can check out the axel nuts and the swingarm bearings while it is off the ground too. Lift/drop from above (reaching around the seat with both arms and grabbing the tire at the top). It should not have any free play.

Yeah i got a dirtbike stand from Harbor Freight. Gonna try this. The front wheel is definitely not balanced, I'll get that done.

Edit: The front forks seem to be tight.

culcune · 06-27-2022, 07:00 PM

I know these bikes are technically off-road bikes, so it could be the stock knobby tires the bike comes with (I am assuming you are riding on the road?) giving you issues. Of course, check all the nuts and bolts and whatnot first, but I wouldn't put it past the stock tires which I assume are somewhat aggressive knobbies. People in the past with new bikes, like the Hawk 250 (also technically an off-road bike which may still, but I recall used to, come with fairly aggressive knobby tires), have complained about wobbles and ended up changing out their stock tires and seen a near complete fix.

Blueridge boyieee · 06-30-2022, 04:29 AM

Not sure if this will help you but I had a similar experience after adjusting the rear spring preload too tight. I wound that adjuster down, say one inch from the bottom threads and much to my surprise, the rear spring has more than enough for my 175 pounds.

After testing out my first adjustment (not enough sag in rear) my bike suddenly developed a wobble at >45 mph. Lowered the spring preload a bit and the wobble is gone.

Whoever said to start with small adjustments on suspension is a smart feller.

Good luck

Thumper · 06-30-2022, 06:10 AM

I am sure that Culcune is right. I get minor wobble on the Templar on pavement, but also slight wobble on my Storm, which was more stable with OEM dual sport tires. The Tusk DSport rear tire I put on the storm is pretty stable. It is the Shinko knobby front tire that is doing it. But it works off-road, so I am OK with it. As I said, it doesn't amplify. It basically wanders..

I just go with it. It doesn't amplify like it did on old 70s Four cylinder bikes that had inadequate triple tree/frame stiffness and forks. Good to know your headset bearings are snug though. If they were loose, it would make it worse.

06-27-2022, 07:00 PM	#5
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,035	I know these bikes are technically off-road bikes, so it could be the stock knobby tires the bike comes with (I am assuming you are riding on the road?) giving you issues. Of course, check all the nuts and bolts and whatnot first, but I wouldn't put it past the stock tires which I assume are somewhat aggressive knobbies. People in the past with new bikes, like the Hawk 250 (also technically an off-road bike which may still, but I recall used to, come with fairly aggressive knobby tires), have complained about wobbles and ended up changing out their stock tires and seen a near complete fix. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	1

06-26-2022, 10:58 PM	#2
BrokeAss Join Date: Mar 2021 Location: Ohio Posts: 43	Loose steering stem bearings, loose front axle, loose rear axle, loose fork legs, out of balance or out of round wheel(s)...
	1

06-30-2022, 04:29 AM	#6
Blueridge boyieee Join Date: Jun 2022 Posts: 44	Not sure if this will help you but I had a similar experience after adjusting the rear spring preload too tight. I wound that adjuster down, say one inch from the bottom threads and much to my surprise, the rear spring has more than enough for my 175 pounds. After testing out my first adjustment (not enough sag in rear) my bike suddenly developed a wobble at >45 mph. Lowered the spring preload a bit and the wobble is gone. Whoever said to start with small adjustments on suspension is a smart feller. Good luck
	1

06-30-2022, 06:10 AM	#7
Thumper Join Date: Feb 2021 Location: Kansas City Posts: 2,344	I am sure that Culcune is right. I get minor wobble on the Templar on pavement, but also slight wobble on my Storm, which was more stable with OEM dual sport tires. The Tusk DSport rear tire I put on the storm is pretty stable. It is the Shinko knobby front tire that is doing it. But it works off-road, so I am OK with it. As I said, it doesn't amplify. It basically wanders.. I just go with it. It doesn't amplify like it did on old 70s Four cylinder bikes that had inadequate triple tree/frame stiffness and forks. Good to know your headset bearings are snug though. If they were loose, it would make it worse.
	1