V-max torks side to side during acceleration , coasting, deceleration

[Fire-medic]

Just because I can't wiggle it is it possible that it still could be swing arm bearings

You can grab it w/the wheel jacked up off the ground to test it. Then grab the front forks at the bottom and see if you get any looseness by moving the fork slider bottoms forward, then to the back. You might feel a 'clunk' and there should be free-play if the bearings are loose/worn. You can try it either w/the wheel on or off. If you try it w/the wheel off, re-install the axle & do it. The wheel/forks should be straight-ahead. You could also show someone what you want done, and then feel at the top of the bottom triple tree stem w/your fingers for any free-play when they push/pull on the bottom of the fork sliders.

Something else which hasn't been mentioned, is if the fork downtubes are straight. You may see something if it was pronounced-enough, but a slight bend from a prior accident might not show-up until you removed each downtube/slider assy, & ran the downtube across a flat plane to check for any 'hop' or out of roundness. Obviously, you do this for the downtube area outside of the slider at the bottom. Any bend will immediately be obvious. Actually, when you try to slide the downtube out of the triple trees, a out-of-true condition will make it very hard to remove the downtube. You might need to use a blade screwdriver to open the triple tree slot to relieve pressure clamping on the tube, either top and/or bottom triple trees.

If the front oil level in the forks is off or different side-to-side, that could affect damping/handling. Also, worn rear shocks could cause a wobble, and it could be just 1 worn shock, too. That's harder to determine w/the spring in-place on-each.

You could make a 2nd-class lever from a strap hinge, and some 2x4's. Have one short approx 12" 2x4 rigidly-fastened at 90 degrees to a 4' long 2x4. Place the strap hinge on the top-side of the short vertical 2x4 so the one rigidly-fastened to the vertical 2x4 is lying on the ground, and the short one is sticking straight-up. Then fasten the remaining long 2x4 to the hinge. It should look like a long "U," lying on its side. Now place the shock somewhere close to the short 2x4 and hold it vertical between the long 2x4's. Mark where the shock would sit and use a hole saw large-enough to cut holes in the top and bottom boards so the shock mounts slip into them. You can now press down on the free end of the top 2x4 and see what kind of resistance you get to compression ('jounce') and rebound (when you release pressure). Crude but effective. You should be able to see if one has a different amount of force to either compress it or if it immediately 'springs-back' upon releasing force. it should exhibit damping in each direction if it is OK.

You can also use the same type to test a starter, just jam the board into the gear to put it under load and energize it. It may spin freely under no-load, but not be able to spin under load. Again, crude but effective.

 

[one2dmax]

I also wonder if you're trying to describe a condition that is caused by head bearings too tight. Basically the bike will not want to go straight and require constant correct to maintain course.

 

[davesax36]

The manual instructions for tightening the bearings is strange, but somewhat sensible. I'd go through the real process will proper specs and everything and see if that fixes it.

Sent from my Galaxy Nexus using Tapatalk 4

 

[leroycp]

Mine did that stock and I changed the head bearings and race and it went away. Locktight the race as they tend to spin / shift.

 

[Doug66]

It feels like a pendalaum pulls side to side , put it on center stand tried to move rear tire feels tiet , maybe swing arm bolts are still a little loose but can tell by hand ?

 

[Fire-medic]

Use a factory manual for the setting of the pivots, very simple but you need a low-reading torque wrench, not a 150 ft/lb one.

 

[jfeagins]

Put your bike on it's center stand. Start the bike. Run it up to about 3rd gear and let it idle down to a calm rpm - 1500 or so, just so it don't die while sitting there (in gear). Observe. See if you have side - to - side runout on that back tire/wheel combo.

My money is that you do. It'd cause all the symtoms you describe, and usually easy to spot while the tire is spinning in place. If it's bad enough, it'll want to wobble the bike right there on the stand. I've seen it too many times. Even with brand new rear tires.

 

[Doug66]

So what do u do to fix it ? New tires ?

 

[DMAN999]

So what do u do to fix it ? New tires ?

If it has too much run out, then yes, replacing the tire is the only way to fix it.
There's some good info here about measuring tire run out.

 

[MaxMidnight]

Put your bike on it's center stand. Start the bike. Run it up to about 3rd gear and let it idle down to a calm rpm - 1500 or so, just so it don't die while sitting there (in gear). Observe. See if you have side - to - side runout on that back tire/wheel combo.

You don't need to have the rear wheel being driven - just place a fixed object such as an axle stand next to the wheel and spin it around.

Look to see if the gap changes. Do this for the rim and tyre.

This process also works for the front (assuming you have lifted the wheel off the ground!)

So what do u do to fix it ? New tires ?

Before you can fix it you need to establish what the cause is.
Make a list of the suggestions made in previous posts and start to work your way through them.

Trying to guess the cause usually wastes time and money.

 

[alorio1]

My money is on the head brgs too tight or the tire/tires did not seat when installed. I've noticed if you install a back tire and the soapy water dries before you get the tire inflated, it will not seat properly and conform to the rims roundness. There is a small line of rubber made onto the tire just above the outer edge of the rim. This line should be even all the way around the top of the rim on both sides, if not, tire will have to be broken down and re lubed with soapy water and re inflated. Sometimes you have to over inflate to get the tire to seat properly.

 

[sdt354]

Mine did that stock and I changed the head bearings and race and it went away. Locktight the race as they tend to spin / shift.

The races are a press fit. There shouldn't be any movement when seated dry.