Problem with binding on the front fork after rebuild

[Draagood]

I just Rogered my fork and everything went well there but I encounter a problem with the fork binding after installation. At this point I know I didn't mount it the right way...because of the binding. But what is the right way on this bike? I found something that could be useful but it doesn't refer exactly at what it could be aligning the fork. http://www.vtr1000.org/phpBB3/viewtopic ... b0#p269755

In some other parts I found that you should jack the front in the air, release the front axle just a bit and the lower triple clamp. Spin the front wheel as fast as you can and apply the front brake and the tighten the axle. After that put the wheel on the ground with the lower triple clamp lose and pogo stick the bike and then tighten the lower triple clap.

Would that work or do you have some other idea?


Before this the fork had no binding and I didn't notice any deformation on the tubes.

[tony.mon]

Try checking each leg individually to see if the problem is in one leg or the alignment.

[bazza696]

Try checking each leg individually to see if the problem is in one leg or the alignment.

That's a good start as Pete L had the same problem with his Suzuki and found that he reassembled the forks like the storm, but I had a different sequence.

[fulviogsx]

I just Rogered my fork and everything went well there but I encounter a problem with the fork binding after installation. At this point I know I didn't mount it the right way...because of the binding. But what is the right way on this bike? I found something that could be useful but it doesn't refer exactly at what it could be aligning the fork. http://www.vtr1000.org/phpBB3/viewtopic ... b0#p269755

In some other parts I found that you should jack the front in the air, release the front axle just a bit and the lower triple clamp. Spin the front wheel as fast as you can and apply the front brake and the tighten the axle. After that put the wheel on the ground with the lower triple clamp lose and pogo stick the bike and then tighten the lower triple clap.

Would that work or do you have some other idea?


Before this the fork had no binding and I didn't notice any deformation on the tubes.

1)loose the stem nut, wheel axle and calipers
2)jack the front bike (front wheel free)
3) take off wheel/calipers
4) loose lower clamp.
At this point ( if all parts are ok) alignment should already be ok.Just to be sure (and check) loose the upper clamp: both the forks have to drop down freely. If they don't , something is bent.
otherwise, if everything is ok, tight upper clamps and successively (and lightly) stem nut and lower clamps. Install wheels in the reverse order

[Draagood]

1)loose the stem nut, wheel axle and calipers
2)jack the front bike (front wheel free)
3) take off wheel/calipers
4) loose lower clamp.
At this point ( if all parts are ok) alignment should already be ok.Just to be sure (and check) loose the upper clamp: both the forks have to drop down freely. If they don't , something is bent.
otherwise, if everything is ok, tight upper clamps and successively (and lightly) stem nut and lower clamps. Install wheels in the reverse order

Thank you fulviogsx,
I didn't think about the stem nut. When I installed the fork I had each fork arm sliding with no problem through the clamps and it was a slippery situation getting them a little bit fixed so I could continue with tightening all the other bolts. I will do this today and come back with results.

[fulviogsx]

1)loose the stem nut, wheel axle and calipers
2)jack the front bike (front wheel free)
3) take off wheel/calipers
4) loose lower clamp.
At this point ( if all parts are ok) alignment should already be ok.Just to be sure (and check) loose the upper clamp: both the forks have to drop down freely. If they don't , something is bent.
otherwise, if everything is ok, tight upper clamps and successively (and lightly) stem nut and lower clamps. Install wheels in the reverse order

Thank you fulviogsx,
I didn't think about the stem nut. When I installed the fork I had each fork arm sliding with no problem through the clamps and it was a slippery situation getting them a little bit fixed so I could continue with tightening all the other bolts. I will do this today and come back with results.

loose the stem nut is essential ;)
If you are sure everything is ok (nothing bent) you can avoid to loose the upper clamp ( and loose related height setting)

[Varastorm]

When I install new to me "eBay" forks firstly I make sure the forks are straight.

I find the easiest way to check this is to rotate the fork in the yoke.

I set them level in the yoke & nip up one side then push the axle through both forks.

Next I rotate the loose leg whilst looking for a weave movement at the lower section of the fork. If you don't place the axle in it's hard to notice a bent stantion with the lower also spinning.

Then the same for the other side.

It's only a quick check but it will highlight an issue if you suspect a bent stantion.

Top tip, never bounce on the front with the yoke bolts loose

Only do it with the fork axle clamps & axle bolt loose

[AMCQ46]

Top tip, never bounce on the front with the yoke bolts loose

Only do it with the fork axle clamps & axle bolt loose

Not heard that one before whats the reasoning?

I have to admit I bounce with everything loose except the top yoke pinch bolts, then tighten the bottom yoke, then bounce, then tighten the fork axle clamps, then bounce then finally I tighten the fork brace.

[Varastorm]

The top tip was a joke

I might be doing this the wrong way but to me if the fork is straight & it slides into the yoke nicely, I nip them up.

I nip the lowers first & then the top. The forks, hopefully straight dictate the top yoke position.

I could be wrong, but I am taking for granted that the yokes & forks are straight.

[AMCQ46]

yes, taking the bike off the stand with all yoke bolts loose would be a problem

[fulviogsx]

yes, taking the bike off the stand with all yoke bolts loose would be a problem

When i was young i did it:stem nut and lower clamps loose

[Cadbury64]

I think the most likely cause of forks binding will be the axle; if it is a snug fit, pushing the axle through the clamp can drag that leg towards the other leg so that the sliders are not parallel. I'd start just by loosening the axle nut and both axle clamps and giving the forks a jolly good bounce up and down a few times, then tighten the axle nut and clamp, another bounce, and then the other clamp.

If that hasn't helped then loosening the top nut on the steering head and the lower triple clamps and repeating the process would be necessary. However if the fork tubes slipped nicely into the triples then I doubt they are twisted.

[fulviogsx]

I think the most likely cause of forks binding will be the axle; if it is a snug fit, pushing the axle through the clamp can drag that leg towards the other leg so that the sliders are not parallel. I'd start just by loosening the axle nut and both axle clamps and giving the forks a jolly good bounce up and down a few times, then tighten the axle nut and clamp, another bounce, and then the other clamp.

If that hasn't helped then loosening the top nut on the steering head and the lower triple clamps and repeating the process would be necessary. However if the fork tubes slipped nicely into the triples then I doubt they are twisted.

In my opinion it s better jack the wheel in the air.this avoid to keep pressure on the clamps...

[Draagood]

Yesterday I did the "job".

Keep in mind that this is happening after a rebuild with lower bushes and oil and dust seals changed, but with more than 200 miles on the road (thinking they would settle by now).

To start with, I wanted to see how much binding/drag I had (rebound off, pre load to 20-30%, bike alone, a zip tie on the arm to measure distances between it and the dust seal):
1 - push down, release and slide the zip tie down to the dust seal (this is where it settles without bouncing on the fork);
2 - lift the front and release it so it doesn't bounce and measure the distance from the dust seal to where the zip tie sits and here I could find as much as 20mm. This is what I considered binding or drag.

I added some fork grease between the dust seal and oil seal and proceeded with taking of the wheel and so on. I even got to loose the upper clamp and pass the arm upper through to understand if there is some bending on the tubes, and nothing.
With lower clamp and axle loose, it looked like I had the same drag.
I bounced the bike a lot and I took the pre load up to almost maximum and after some more bouncing and measuring and so on, I got the drag to be of some 5mm!!! with the pre load fitted for my weight (75kg dry).
Now, like I said, the bike has been on the road for more than 200 miles but it looks like it might have been the new parts that were causing this drag.
What do you think?

[tony.mon]

Isn't that called "sag"?