Author Topic: Front end issue??  (Read 839 times)

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Offline JS550

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Front end issue??
« on: May 02, 2009, 10:37:39 AM »
My bike , 75 750k, at around 40 mph gets a undulation or kinda hop feel, feels like its in the front? Not so bad that you cant ride but is noticeable. I have a new front tire & progressive springs in the forks. Bearings, wheel out of round, any ideas?
Jim
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ev0lution7

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Re: Front end issue??
« Reply #1 on: May 02, 2009, 12:06:42 PM »
put the bike up on the center stand or jack the front wheel up so it spins freely!!! then spin it.... IS it out of round??? are all the weights to balence the wheel on....

now 2nd test... turn the handle bars do you FEEL a notch or does it FEEL loose??? if you bike is the one in your sig... then did remember to put in TAPPERED roller bearings... did you tighten them down enough... on a tappered bearing you need to go back after about 500 miles or so and tighten it down a little more or at least check it!

Offline WFO

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Re: Front end issue??
« Reply #2 on: May 02, 2009, 12:19:39 PM »
Was the front wheel ever balanced?
82 cb650 sc nighthawk - 78 kz 650 b

Offline JS550

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Re: Front end issue??
« Reply #3 on: May 02, 2009, 02:10:11 PM »
No I didnt put tappered bearing in. Im gonna do the spin check & take a look, I changed the tire myself & havent taken it in to be balanced yet. Guess I could have thought of the obvious first huh? doh!
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Offline chrislib

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Re: Front end issue??
« Reply #4 on: May 02, 2009, 04:17:14 PM »
I had the same issue, tapered bearings in the neck and a Hondaman swing arm overhaul have eliminated it so, ck yer head bearings and swing arm side play, probably find both out whack.
Chris...closet Idlefiddler
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1973 CB750K...CANDY BACCHUS OLIVE

ev0lution7

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Re: Front end issue??
« Reply #5 on: May 02, 2009, 08:23:57 PM »
tell ya what with tappered bearing and hondaman swing arm... my bike feels soooo confident i can scrub the EDGE of the tire and scrape pegs on BOTH sides!!!!!!!!!!!!!! it feels great!!!!!

Offline mystic_1

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Re: Front end issue??
« Reply #6 on: May 02, 2009, 08:36:19 PM »
Almost certainly wheel balance.

Tires have the lightest spot marked on them with a little circle painted onto the tire.  Do believe you want that aligned with the valve stem.

Also +1 to what ev0lution7 said, check for roundness.  Sometimes the beads can settle in off-center.

Did you seat the bead well?  I like to overinflate a bit to pop the beads on firmly and then let some air out to come back to spec.  Don't over-do it.

Poor man's balance check:  prop up bike, spin tire.  Allow it to come to a stop on it's own.  Mark lowest point.  Repeat several times.  Tire stops in same place each time = out of balance.  Tire stops at random points = close enough for now.

hth

mystic_1
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