Motorcycle Forum / General / Sportbikes / February 2005

I think it may be a communication problem in the manual.
Check to make sure the rear wheel is aligned properly on the swingarm.
Put it on  the rear stand and see if the forks line up with the wheels, etc.

A bent frame could be another possibility.

I (briefly) had a BSA A50 back in the 70s that pulled to the left. One of
the previous owners had used it with a sidecar, which had distorted the
frame. Luckily, I was able to get a cheap frame from a breakers yard.

be pulling to the left because of either a improperly >installed tire
or a bent fork.  Has anyone out there ever had a >tire that made their
bike pull to one side?  I don't get how it >works...  Thanks!

Yes, but usually riders complain that their bike is pulling to the
right, but that the front tire is wearing out on the left side more
than on the right side. That's because 2-lane roads are usually
crowned, and while riding on the right hand side of the road, the
motorcycle tends to pull right and the front tire tries to correct for
the pull to the right...

You may not have a bent fork. It's possible that you didn't get the
rear axle spacers on the right sides of the axle, or that the rear axle
is isn't quite straight across the swingarm. This may point the rear
wheel off to the right a little bit and the front wheel will try to
correct for it by steering to the left and your bike will turn left
easier than it does right...

You can't trust the rear axle alignment marks, there's too much slop in
the adjustment system, you need to measure, if at all possible...

If you can hold a tape measure along the swing arm and measure from the
center of the swing arm pivot bolt to the center of the rear axle on
both sides, the difference in measurement should be more more than
1/32nd of an inch for good alignment...

Usually the exhaust pipe or some bracket gets in the way of a good
measurement. In that case, use the string method...

I won't type that out again, you can google search for
"kaybearjr@aol.com" +string +alignment

Remove the Kerry-Edwards sticker and it will be fine.

"Pulling to the left," mmm kay.  Our POS '75 Plymouth Volare with a
bad tie rod pulls to the left.   Any bike with unstable handling
should be parked, immediately, 'cause something's very wrong.

Touble is, some clapped-out 17 y.o. literbike, it could be damn near
anything.  Minor miracle it still runs, though those things WERE the
cat's meow back when they arrived in '87.  I remember.  

God knows what rubber those things wear, though presumably someone's
still making bias-belt tires.  Thinking back to the days of Metzeler
ME99A rear and ME33 front.  Pre-radials, which didn't make a big
splash until the early 90s.  Point being, I'd check inflation and
tread profile first.  The tires should be balanced, too.

Next is fork tube position in the triple clamp.  Make sure they're
both at the same height, eh?

If the fork oil hasn't been changed since Clinton left office, might
want to give that a go, too.  I've seen stranger things than
mismatched fork oil levels, especially if some jackass dealership did
the job.

Make sure the rear wheel's aligned correctly.  

Not sure how to tell if a fork's "bent" other than the obvious.  If
it's that obvious, hopefully you wouldn't be riding it.

Worst-case, you've got frame trouble.  If it were worth it (it isn't)
I'd say take a trip to your nearest Compu-track.  Coleman did, with
his Gixxer 1000, and benefited greatly he says.  Even modern bikes are
off at least a couple millimeters.  Not sure what they can do with the
engine still in the frame, but one never knows.  

If any of the above cost more than $500, park it.

'-----------------------------------------------------
' Daniel Bannon
' NW WA State, U.S.A.
' 2003 ZX636B Hercusaki, 1999 CBR1100XX
'-----------------------------------------------------

Micah,

I don't have much faith in the string form of the string method.

My version is:  Go to Home Depot and buy an aluminum extrusion.  I got
an 8 footer with about a 1-1/2" square cross section.  I use it
everywhere I need a long straight edge.  Memory says about $12.

Now, measure the cross section of the front and rear tires.  Subtract
F from R and divide by two.  Call that D.  If you aren't familiar with
this, the easy way is lay two boards on opposite sides of the tire and
measure the distance between them.

Now, lay the straight edge solidly against the rear tire and have a
friend or a couple of clamps hold it..  Turn the fork until the front
tire lines up with the straightedge.  Measure the distance of the gap
between the front tire and the straightedge toward the front of the
wheel and the rear.  The two measurements should average D.  If the
average is greater, your rear wheel is aimed to the left of straight
ahead.  If less, to the right.  Loosen the rear axle mounts and
correct as required for your machine..

You can do it with a string, but I find this way a lot less fussy.  

Remember, you are talking movements of about 1/32" to correct this.  

Don't forget to maintain correct chain tension; get the alignment
right, then move both sides EXACTLY the same amount to get the correct
chain tension.  My - modern - bike calls for about 1" of play; YMMV.

Good luck

D