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Old 04-28-2012, 08:14 PM   #511
hardwaregrrl
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Quote:
Originally Posted by Stagehand View Post
my experience is that the head bearings take a good while to stop moving after you take them apart. Lots of adjusting till they settle.

YOu dont really think they are shot, they are new with the fork swap, right?

Otherwise, of course you are not bottoming out anywhere or anything...
The thing is, I cannot for the life of me get the top clamp to seat down more. I was thinking about just taking the triple out and repacking the bearings. I just meant I hope I didn't toast them today bashing the shit out of them I couldn't help myself..... The play in the head is audible. I mean, you seriously can hear it. Wasn't that way 2 weeks ago, but after my off road run last weekend, I noticed the play.
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Old 04-29-2012, 12:46 AM   #512
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Originally Posted by hardwaregrrl View Post
So looks like I'll be taking things apart tomorrow and regreasing and preloading tomorrow. I hope that's all it takes. Anybody got an ideas????
What pre-load? There really shouldn't be any.
Nip up the adjuster nut to a max of 0.6Nm to "bed" them and squeeze the grease out. Back it off a tiny bit.
Test: Does the steering "drop" to both locks? Keep nipping it up a little bit if it "flops". If too tight, back it off and start again.

The nut atop the triple should be feckin' tight - 107Nm, then tighten the stanchion clamps.

'swot I do.

John
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Old 04-29-2012, 04:31 AM   #513
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Hi John, I think your boxersupplies clamps work a bit different to our (ktm style) Rdubb ones. Although I am still actually a little confused about how to set the load on our bearings with these clamps- the way I have heard it described in this thread so far doesn't really make sense to me.
This is the post that Solo quoted,
Quote:
Originally Posted by Windy View Post
From the LC8 repair manual:

loosen the 5 clamp bolts on the top triple clamp and turn in the blind nut until no clearance is left.

NOTE: do not tighten the blind nut since you may damage the bearing.

Gently tap on the top triple clamp with a plastic hammer to relieve any distortion and tighten the 5 clamp bolts (20 Nm).

I always read that as 'hand tight', certainly not '...110-125 Nm...'

Phil
So, is the 'blind nut' the bolt that goes into the top of our stems?
If so, then turning the blind nut in 'till there is no clearance', then tapping the triple, and tightening things up doesn't seem like it is going tight enough on the bearings to me. I'd swap 'no clearance' for 'correct bearing preload'.

Jenna, my 'logic' tells me to to loosen all the pinch bolts on the top clamp (four on fork tubes, two on stem), then I would tighten the bolt that goes into the top of the stem (blind nut?) and tap the top triple gently to make sure it tightens up evenly and slides over the fork tubes- I might also at this time have some weight bearing on the front wheel so I wasn't trying to pull up the front end with that little bolt threaded into aluminium- when the bearings feel correctly tightened I would then re-tighten all the pinch bolts on the top triple. At this point, theoretically one could loosen off the bolt into the top of the stem a little, as the stem pinch bolts are now maintaining the bearing preload, but considering it shouldn't take all that much torque on that top nut to get to this point, I'd just leave it be.
I think this is the way I did mine but I haven't put many miles on it yet. Is this the way people are doing it?


btw, I checked out my forks today. Took the wheel off to check each fork independently. The rebound side was a bit stiff and was making a little noise when spinning the slider around the tube. It was also a lot stiffer/stickier moving it up and down compared to the compression fork.
I partially pulled it apart- top section of my new spring had grown some surface rust. Cleaned that all up and drained and cleaned out the fork- maybe 600cc of oil in there, very thin red oil (felt like 5w or less) with some very grubby oil settled on the bottom.
I re-filled with 10W oil (a mix of 5W and 15W- the only stuff I had on hand). 800cc. Didn't have enough oil to do both sides. This will basically be a flushing oil change to slosh around in there until I properly pull them apart. I'll probably grab some more fork oil or ATF tomorrow to do the compression side and then do a few more laps around my neighbourhood.

The action for the rebound leg is definitely smoother now, the noise is gone, and I was hoping I had solved my stiction issue, but it hasn't actually done a great deal. The compression side makes a tiny bit of noise too, so I am suspecting it too has a little bit of surface rust on the top of the spring.
Deal with that tomorrow with some oil on hand.
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Old 04-29-2012, 06:22 AM   #514
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Just an addendum to the last post,

I don't really like the idea of torquing up the bearings with that stem bolt and having to pull the whole front end up as you do this- I'd hate to strip that threaded aluminium- but to check for the correct torque on the bearings it obviously helps to have the bike on the centerstand and the forks 'hanging'- so there is another way to do it (I think)

Have the bike on the centerstand with the front wheel not touching the ground:
On the upper triple, loosen to two pinch bolts for the stem but leave the four fork tube pinch bolts tight.
On the lower triple, loosen the four fork tube pinch bolts.
(Now the weight of the front end is hanging off the frame but you can still torque up the stem bearings and all you are doing is pulling up the lower triple clamp over the fork tubes)
Now tighten the stem bolt from the top and occasionally tap the lower triple up as you go.
You can now turn the bars and do the 'let them fall to the side' test to check your bearing torque. Once it feels right, tighten up the two stem pinch bolts and the lower triple pinch bolts, and it should be good to go.

Does that make sense?
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Old 04-29-2012, 06:49 AM   #515
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So when I got the forks back from Kent, he asked me to leave them in the lower clamp and install the triple with the forks in the clamp. So this time, I'll ignore his advice, and remove the forks and install the triple without the forks. Or am I an idiot? I mean, there isn't just a little play, there is A LOT of play.
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Old 04-29-2012, 07:13 AM   #516
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To remove my front end, I take the wheel off, then leave the triple in the bike and just slide my forks out one at a time- after that I remove the triple clamp if I need to. And I do the reverse to put the front end back on. I don't really see the problem with that. it feels like it works really well.

but I still think you are going to have to torque the bearings with the forks in (as they probably won't align properly otherwise).
You should at least be able to get a good idea what is happening with the forks out first and then muck around with the triple and check those bearings,
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Old 04-29-2012, 07:29 AM   #517
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Quote:
Originally Posted by ontic View Post
Hi John, I think your boxersupplies clamps work a bit different to our (ktm style) Rdubb ones. Although I am still actually a little confused about how to set the load on our bearings with these clamps- the way I have heard it described in this thread so far doesn't really make sense to me.
This is the post that Solo quoted,


So, is the 'blind nut' the bolt that goes into the top of our stems?
If so, then turning the blind nut in 'till there is no clearance', then tapping the triple, and tightening things up doesn't seem like it is going tight enough on the bearings to me. I'd swap 'no clearance' for 'correct bearing preload'.
I just read my KTM manual and the procedure that "Windy" gave you is the "KTM way"
I matters not what the application is, but if you preload a taper bearing it will be toast in no time at all.
When they are/were used in car wheel bearings, the setup was always to nip it up and then back it off so that you could just move the washer with a screwdriver.

The reason those triples have the 4mm recess at the top of the stem hole is so the the blind nut bears on the triple and pulls the stem up into it and then you lock it all of in position.
There is no adjuster nut under the top triple like mine has.
On my triples, all the adjustment is/can be done with the top triple off the bike.


Cheers,
John
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Old 04-29-2012, 08:16 AM   #518
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John, this was my worry early on, not having the adjuster nut. Our blind nut is soft alum. and everybody says to not crank down on it and that using a mallet is enough to set the bearings. I'm almost tempted to press this stem out and install my dr 650 stem that is male threaded instead of female threaded like outs.

I'm hoping that the weight of the fork tubes in the triple when first installed maybe "cocked" the race or bearing and it's as simple as resetting. For the record, I rode the piss out of this bike the last few weekends!!!!


Quote:
Originally Posted by redboots View Post

The reason those triples have the 4mm recess at the top of the stem hole is so the the blind nut bears on the triple and pulls the stem up into it and then you lock it all of in position.
There is no adjuster nut under the top triple like mine has.
On my triples, all the adjustment is/can be done with the top triple off the bike.


Cheers,
John

hardwaregrrl screwed with this post 04-29-2012 at 08:27 AM
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Old 04-29-2012, 09:52 AM   #519
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Found the problem!



I mean, what a f#%^ing pain in the arse!



On top of it all I cannot get the top bearing to let go. And while tapping on the stem the internal threads got buggered!! I'm seriously thinking about pressing the ktm stem out and putting the dr stem in. Anybody see a problem with that??
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Old 04-29-2012, 10:00 AM   #520
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I just checked all my sag figures and the back sag is a little too much. I seem to remember I had the rear shock preload set to 5mm at the last rebuild...
If I put it back to 17mm it should be about right

Any comments on the front?
(I have a theoretical 220mm of travel and can drop the forks by another 20mm)
I have 20l of fuel in the tank and I weigh about 78kg

Cheers,
John

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Old 04-29-2012, 11:19 AM   #521
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I have 200mm of travel in the front. The forks have been shortened to the original R80G/S length.
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Old 04-29-2012, 12:43 PM   #522
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Quote:
Originally Posted by hardwaregrrl View Post
I have 200mm of travel in the front. The forks have been shortened to the original R80G/S length.
Whats your sag? ...not to get too personal

I had min shortened by 85mm so they should be 20 mm longer than standard and that much is pushed through the clamp.

I'm afraid that that bearing of yours looks like a classic overload and cage binding

Cheers,
John
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Old 04-29-2012, 12:48 PM   #523
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Quote:
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Whats your sag? ...not to get too personal

I had min shortened by 85mm so they should be 20 mm longer than standard and that much is pushed through the clamp.

I'm afraid that that bearing of yours looks like a classic overload and cage binding

Cheers,
John
Yeah! You're right on the bearing!!! I cannot find my sag stats right now and certainly am in no position to measure them for you!! uhmmm....I'm thinking back on the install, and remember the bearing cage skipping out for a bit and then it was corrected, and the blind nut being used like a adjustment nut. So, both things caused this. Bummer is now I need to fix the thread on my stem...hoping my local machine shop can help me out with this.
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Old 04-29-2012, 03:05 PM   #524
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Quote:
Originally Posted by redboots View Post
I just checked all my sag figures and the back sag is a little too much. I seem to remember I had the rear shock preload set to 5mm at the last rebuild...
If I put it back to 17mm it should be about right
If you have a G/S, and the 170mm of wheel travel (as stated in the manual) is correct the rear sag if 24%... which looks to be in that general guideline, if not on the firm side a bit.

Also, the spec for the Ohlins spring is total length of 213mm and not a mm of pre-load per Dan Kyle Racing.

Your front is at 30%, I am going to try and balance the front & rear to have the same sag FWIW
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 04-29-2012, 03:49 PM   #525
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Originally Posted by redboots View Post
I just read my KTM manual and the procedure that "Windy" gave you is the "KTM way"
I matters not what the application is, but if you preload a taper bearing it will be toast in no time at all.
When they are/were used in car wheel bearings, the setup was always to nip it up and then back it off so that you could just move the washer with a screwdriver.
Well, you and others seem to know what you are saying but that is the bit I don't get, in my mind, unless there is a little bit of preload then it is still 'loose'. Setting a bearing exactly on 'no play' is a minutely small target to hit and one that moves away with any bearing movement (race seating a touch deeper) or bearing wear and changes with thermal expansion- unless of course 'no play' is an acceptable 'grey band' in which case I think it must include a little a little preload on its upper limit and play on its lower.

That test of the forks slowly falling down to the side to me seems like the method of determining the correct amount of preload- and I'll admit again that it is not much. With no preload they fall down to the side too quickly and feel too loose. My 4x4 has taper wheel bearings and like most everything else, I change them myself. I am familiar with the method of nipping them up and then backing them off- and was shown how to do this- but in that application too I would consider that to be a very small amount of preload rather than none I suppose I am either doing or just thinking about it wrong.
Also, are we expecting a great amount of thermal expansion in steering head bearings (such as wheel bearings have to put up with)? Surely they don't get that hot and that if so we can snug them up a bit tighter (trying not to say use more preload)
I'm just trying to understand this.

Jenna, real bummer about the thread on your stem. For people used to the bmw (and other) system of the adjuster nut under and locking nut over, this does seem an odd system.
I personally wouldn't go reaching for the DR stem just yet- we must be loosing something in translation as all those hoards of KTM users can't be that wrong can they?
If you get your thread working again, I am more and more liking the way I described it in post 514. Leave the forks hanging on the centerstand, loosen the upper stem bolt pinch threads and the lower triple fork pinch bolts and then adjust the steering head bearings. The forks are in but far enough out of the equation to not cause confusions.
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