[DaBBSitta]

Hey guys, I need help...

I have been chasing a front end vibration for some time now. It used to come and go at different speeds but now it seems to be only around 50 mph. Recently I changed the clutch disks, plates and springs and that made the vibration go away from all other speeds except for right around 50 mph. Here is a list of things I have already done chasing this.

New front tire/ balanced
Front forks rebuilt with new springs and fluid
Steering stem bearings
Drive sprocket
Drive chain
Rear hub dampers
Clutch plates, disks and springs
Oil change with recommended oil

Any and all input, suggestions, ideas on what else I can check or tear into are greatly appreciated.

2000 Shadow ACE VT750 CD2 Deluxe/ Bobber 27K miles...

Thanks in advance... Andy

 

[jpr1968]

What about wheel bearings? Motor mounts. Can't imagine that clutch would cause a front end vibration.

 

[smilie]

^+1 on the wheels bearings

 

[2500hdon37s]

also check the balance of the rear tire.

 

[John Hopkins]

Hey guys, I need help...

I have been chasing a front end vibration for some time now. It used to come and go at different speeds but now it seems to be only around 50 mph. Recently I changed the clutch disks, plates and springs and that made the vibration go away from all other speeds except for right around 50 mph. Here is a list of things I have already done chasing this.

New front tire/ balanced
Front forks rebuilt with new springs and fluid
Steering stem bearings
Drive sprocket
Drive chain
Rear hub dampers
Clutch plates, disks and springs
Oil change with recommended oil

Any and all input, suggestions, ideas on what else I can check or tear into are greatly appreciated.

2000 Shadow ACE VT750 CD2 Deluxe/ Bobber 27K miles...

Thanks in advance... Andy

When new steering bearings are fitted it is common to have to retighten them after about 500 miles..

You can check that the wheel is still balanced by jacking up the bike so that the front wheel is off the ground and then spinning the wheel, when it stops turning put a chalk mark at 6 o'clock and then spin it again, put another chalk mark at 6 o'clock repeat this a few times more and if all the chalk marks are on the same side of the wheel you need a weight added to the opposite side.

With the front wheel off the ground grip the wheel at three and nine o'clock and push with one hand and pull with the other if you feel any movement or hear a clicking sound the wheel bearing is worn out.

As said sometimes if the rear wheel is damaged it can make the front end vibrate..

John.

 

[DaBBSitta]

Thanks guys. I'll check the bearings and everything else on both rims, the steering stem bearings for tightness and all the motor mounting points.
This will take me some time so I will update after I do all this.

Meanwhile, I'm open to any and all additional ideas and suggestions.

Thanks again...Andy

 

[KCochran]

Not wanting to hijack this thread but if I have a vibration problem and the cause is not obvious, what should I check first? Tire balance? Other?

 

[smilie]

All of what was just mentioned above would be a good place to start. If you can isolate the vibration i.e. front, rear, engine, etc., it would sure help to narrow it down. Probably wouldn't hurt to start your own thread as to not hijack this one.

 

[KCochran]

Thanks. It has not happened to me yet but you never know!

 

[Pavogg]

Wheel bearings or Front tire out of round

^^^^ +2 on the wheel bearings

Also seen vibration a one speed on a tire and wheel that balance perfectly but are not concentric with the axle. This causes loping. The tire and wheel can be perfectly balanced, perfectly circular, but, not concentric with the axle. In other words the center of the diameter of the wheel and the axle are not the same point. This is called eccentricity (like a lobe on a cam). Check this by using a fixed point, like the fender tip, and hold a pencil against the fender tip so it just hits the center of the tire. Now spin the tire and see if it pushes the pencil away or a gap appears. If it does and it is a cast wheel the tire is bad from the manufacturer. If it is a laced wheel (spokes) the rim may need to be tuned by a professional (he/she will have to loosen the spokes to recenter the hub).

 

[2500hdon37s]

^^^^ +2 on the wheel bearings

Also seen vibration a one speed on a tire and wheel that balance perfectly but are not concentric with the axle. This causes loping. The tire and wheel can be perfectly balanced, perfectly circular, but, not concentric with the axle. In other words the center of the diameter of the wheel and the axle are not the same point. This is called eccentricity (like a lobe on a cam). Check this by using a fixed point, like the fender tip, and hold a pencil against the fender tip so it just hits the center of the tire. Now spin the tire and see if it pushes the pencil away or a gap appears. If it does and it is a cast wheel the tire is bad from the manufacturer. If it is a laced wheel (spokes) the rim may need to be tuned by a professional (he/she will have to loosen the spokes to recenter the hub).

But if that were the case most likely it would only get worse as speed increases.

 

[John Hopkins]

Pavogg does have a valid point, a badly fitted or poorly manufactured tire can cause problems, the only thing I would add is to replace the pencil with a piece of chalk which will leave a mark on the tire, then repeat the test on the wheel rim.. if the marks are in the same place on both the tire and the rim you either have a warped wheel or a damaged bearing, if the rim runs true but the tire has a high spot the tire has been fitted badly and the fault may sometimes be cured by deflating the tire and reinflating it..

John.

 

["Captain D"]

I had a Commander II on the rear that was "out of round" which caused a "hop" (my description) which went away when I was at highway speed...
Rim true, but tire was not!

Laptop diagnostics is guess work

LLLL bring it over, the lift is empty...

Merry Christmas
Ann & Dennis

 

[DaBBSitta]

It is the rim. The runout is out and it is not perfectly round. Needs to be tuned. I tried my hand at it and got it very close. The vibration/ hop is almost non existent now. Feels like rough pavement at times. Some of the spoke nuts are so jacked up that I had to use vise grips to turn them.

So...should I respoke the rim or just replace it?

 

[John Hopkins]

It is the rim. The runout is out and it is not perfectly round. Needs to be tuned. I tried my hand at it and got it very close. The vibration/ hop is almost non existent now. Feels like rough pavement at times. Some of the spoke nuts are so jacked up that I had to use vise grips to turn them.

So...should I respoke the rim or just replace it?

Just replace it..rebuilding a spoked wheel is a professional job, do it wrong and you can kill yourself ...

John