stem /steering column bearing adjustment - some input ?

[jloi]

I just replaced the bearings  in my steering column , upper and  lower  including  races .  2014 Tao Tao 150  .  I previously  replaced front and rear shocks  x amount  of miles ago , maybe 1000 miles  on these shocks  probably less .  After  the time I replaced front shocks  I eventually developed a shimmy in the front end . Some shaking and bouncy  ride at higher speeds . I adjusted the bearings at that time but it never went completely away.  So now I've just replaced and adjusted  the bearings.  My best adjustment  I still have a little shudder if I take left hand off handlebar  and it's still bouncy at higher speeds. I don't remember the scooter  doing this  until I had  it for maybe 2 years .  I've read where some Chinese scooters  have  this  issue kind of naturally and  it's to be expected  to have a certain amount  of this .  Any input from anyone would be appreciated and  can anyone verify  if this  is true about some scooters.

 I don't drive around 1 handed  that was just to check  for head shake  .

 The wheel  rotates true  no crookedness ; same with rotor .  Front wheel bearings seem fine; spins freely , no noise etc .

 I may take  it somewhere and  have the wheel balanced ; after I research it first and see if I want to tackle  it  myself . I'm  pretty sure I saw  Brent has a tire balancing  vid .

 I enjoyed immensely ,following everyone's pics and stories during Scoot Week. Congrats to everyone  who took part and to Brent for having such a fine forum . Maybe  next time I can take  part .  Excellent trophies too BTW

[snaker]

I've had lots of motorcycles and guestimated that I racked up over 170,000 bike miles. A couple front end issues were caused by steering, bearings, forks. The vast majority of issues were caused by front tire tread and were fixed with a new tire. I don't think it was a balance issue, just tread that was wearing bad.

[tortoise2]

Jun 10, 2019 15:21:22 GMT -5 jloi said:

developed a shimmy in the front end . . don't remember the scooter  doing this  until I had  it for maybe 2 years 

Any chance the shimmy is a tire wear related issue?

MICHELIN offers Power Pure SC tires in 130/60-13.

[jloi]

That's good enough for me . I'll check into the tire right away. It's at least 4 years  old. I think appearances can be deceiving .

                                              Thank you , guys

 edit: what about mixing different tires, brands I mean .   I just put a brand new tire on the rear when I bought a new rear rim . I don't really  know diddly about tires .  I think it's a safe bet  they should be  a set.

[jackrides]

A set is best 'cuse then there should be no questions of compatibility. Find a way to have your scoot stable with the front wheel off the ground. Now get a friend to help by holding the bars Steady. Try to slide the wheel back and forth on the axel. Next, from the side, grab the top and bottom of the wheel, push on top pull on bottom and reverse. Any play? Now, push/pull forward and back on the fork tubes. Any play or 'bump' feel?
Next, gently turn the bars right to left and back. Any bump in the middle?
Yes check the wheel balance. Clamp the axle in a vise and heat the bearings a little so it spins easier. Spin and mark (chalk) the low spot (high spot if you are That kind of person) about 4 times. Marks all over = clean bearings well and start over. (Grease bearings well before putting back on scoot.) Marks close together = add a gram weight and keep going till marks are random.
Drink beer.