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Front wheel spacer loose


tmcafe

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Thanks that soun ds like a useful tool.

Still wondering why do some folks mention the potential issue of putting too much pressure on the wheel bearings if the axle is torqued before the pinch bolts?

It is not torquing the pinch bolts before torquing the axle nut that can cause too much pressure on the bearings, it is over torquing the axle nut can shorten the length of the bearing spacer causing side loads on the bearing when you tighten it down that should not be there. Wheel bearings are not designed for continuous high side loads like that. The reason the spacer tube is there between the bearings is to keep the inner races of the bearings a preset distance apart so that the torque used to secure the axle is not transfered to the bearing.

As far as the axle setup you mention, it sounds familiar. I am thinking I have seen something like that before. The tool for tightening the axle was a tube with two short nubs that when you inserted the tube into the axle locked into the notches in the axle. You then stuck a screw driver or other such rod threw two opposing holes in the other end of the tube to hold the axle in place.

Did you look through the tool kit that came with the bike. As crazy as it sounds there might be a tool in the kit that does just what you need. Or not.

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It is not torquing the pinch bolts before torquing the axle nut that can cause too much pressure on the bearings, it is over torquing the axle nut can shorten the length of the bearing spacer causing side loads on the bearing when you tighten it down that should not be there. Wheel bearings are not designed for continuous high side loads like that. The reason the spacer tube is there between the bearings is to keep the inner races of the bearings a preset distance apart so that the torque used to secure the axle is not transfered to the bearing.

As far as the axle setup you mention, it sounds familiar. I am thinking I have seen something like that before. The tool for tightening the axle was a tube with two short nubs that when you inserted the tube into the axle locked into the notches in the axle. You then stuck a screw driver or other such rod threw two opposing holes in the other end of the tube to hold the axle in place.

Did you look through the tool kit that came with the bike. As crazy as it sounds there might be a tool in the kit that does just what you need. Or not.

Thanks. It is obvious the pinch bolts don t do anything to the bearings. While I understand that the spacers keep bearings from being affected by the side loads caused by torquing the axle, I m still wondering about the effect on the forks. They are meant to be as straight as possible in order to minimize stiction. Torquing the axle would change the distance between the fork bottoms--unless the distance was secured by the pinch bolts. OTOH it might be that the torque value for the axle just brings the fork bottoms together at the correct distance. Clearly the axle is designed to be torqued on its own (without resistance as in the case with the pinch bolts already torqued). I saw the tool you describe in web pics. Toolkit doesnt have it--no surprise. It was prolly put together as a standard kit for V11. It also has no tool for the ft axle nut. I bought a fairly inexpensive 30mm spanner for that.
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Guest ratchethack
Torquing the axle would change the distance between the fork bottoms--unless the distance was secured by the pinch bolts. OTOH it might be that the torque value for the axle just brings the fork bottoms together at the correct distance. Clearly the axle is designed to be torqued on its own (without resistance as in the case with the pinch bolts already torqued).

TMC, it seems you've not yet fully grasped how this works.

 

Tightening the pinch bolts before torquing the axle nut DOES NOT, and CANNOT secure the proper distance between fork lowers! Doing this will all but guarantee that your fork will suffer binding and stiction to some degree, and that your brakes will likely drag.

 

It is PRECISELY because of this, that doing it correctly per the Guzzi manual is the ONLY correct way to do it. Same with every other manual on every bike ever made, and every fork ever made with pinch bolts on one fork lower and either a threaded hole or axle nut on the other fork lower. Again, if you do it by the proper procedure, all the slack in the "stack" on the axle (which continues to be taken up all the way up to final torque on the axle nut) is taken up in full compression, reaching its FINAL dimension BEFORE you tighten the pinch bolts. THIS AND ONLY THIS ensures the correct distance between fork lowers and a non-binding fork. Works every time.

 

Hope this helps, my friend. :luigi:

 

EDIT: There's been enough persistent confusion here that I suspect you're not using correct terms to ID the basics here. If you could provide a photo of the "nut" you've been referring to as installed on the fork, all will be made clear, and we can get you back on the road with a smooth operating fork with non-dragging brakes PDQ.

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TMC, it seems you've not yet fully grasped how this works.

 

Tightening the pinch bolts before torquing the axle nut DOES NOT, and CANNOT secure the proper distance between fork lowers!

 

It is PRECISELY because of this, that it is NEVER the correct procedure -- per the Guzzi manual and every other manual on every bike ever made, and every fork ever made with pinch bolts on one fork lower and a threaded hole or axle nut on the other fork lower. If you do it by the proper procedure, all the slack in the "stack" (which continues to be taken up all the way up to final torque on the axle nut) is taken out in compression, reaching its FINAL dimension BEFORE you tighten the pinch bolts. This AND ONLY THIS ensures the correct distance between fork lowers and a non-binding fork. Works every time.

 

Hope this helps, my friend. :luigi:

Thanks RH. Indeed the axle design--with the slots to hold it and counter the torque on opposite side indicates that it is to be torqued without the fork bottoms pinched by the bolts (four, two per fork on my bike--more like type 1 in the manual). FWIW the manual mentions the speced torque on the axle being applied last--see F p. 4, but we know Luigi the manual editor should be taken with a grain of salt. Torquing the axle first does make more sense. Grazie!
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  • 7 years later...

tmcafe, you have Ohlins forks? Mine look like this. Yours are different?

My 2002 Lemans resembles the pair of photos in Post #10.  Large recessed hex on right side of axle.  Right axle only has pinch bolts.  Axle threads into left fork leg (no nut).  But after changing my tire yesterday, it seems that the right spacer has some play in it.  I assume this is not normal.  I snugged the axle about where I found it.  And I know the pinch bolts will keep the axle from rotating.

 

Is there a specified torque that I should be using for the axle before I snug the pinch bolts?  I realize that I should allow the right fork leg to "float" on the axle by bouncing the front forks prior to tightening the pinch bolts.  But so far, I don't see the right spacer going to "zero" clearance before I do this.

 

And, of course, the 2002 Owners manual shows a nut on the left fork leg.   Clearly not what I have...

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My axle doesn't thread into the fork leg. It is hollow and threaded at the right end (not like in the manual) and is tightened by a large nut. I'm sure it was designed for bikes that have a damping adjustment screw on the bottom of the fork leg hence the notch at the opposite end.

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Still no cure...I did look up the torque spec for the front axle, and I believe it came out to be about 70 or so Ft/lbs.  So I loosened the pinch bolts on the right fork leg, loosened, then tightened to 70+ ft/lbs.  The axle doesn't draw itself into the threaded leg any more than "snug", as far as I can see.  And the spacer remains rattly - loose on the right side.  

 

Anybody else have a cure for this?  Again, my 2002 Lemans resembles the pair of photos in Post #10.

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Check to make sure the brake calipers and discs are not preventing the wheel from tightening down.

Think about what you are doing. You are tightening the wheel against the fork leg on the side that has the threads, whether they are a threaded nut or the  fork leg itself is threaded does not matter.

If you tighten against that side of the fork, what could prevent you from being able to tighten the wheel against the fork leg?

Tightening the axle is no different then tightening a bolt. There should be no looseness once tight.

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The photos you referenced in post 10 are the same as my Ohlins forks on my 2002 Scura - but the 2002 LeMans came with Marzocchi forks. That suggests that somebody upgraded (good news for you).

 

If the above advice doesn't work, maybe you don't have the correct spacer for the Ohlins. I was just looking at the parts manual to verify that they have different part numbers. I think you would be wise to download a parts manual and compare what you have to the illustrations.

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The attached pdf file is from 2 pages of one of the shop manuals that I downloaded.  It claims that there can be 2 configurations of the front forks (and of course, it does not show the spacer!):

 

 

 

Having trouble attaching file.  Could be our filters where I work.

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Most early Marzocchi have an axle that shoulders from the right, pushes through both forks, and nuts from the left with a pair of pinch bolts on both fork legs. But, there are V11 with the earlier (Sport 1100/ 1100 Sport) configuration, as shown, that are not Öhlins. I've never seen that on a 2002 LeMans, but perhaps they were changed? In that case, if the (left side) spacer was used from the Marzocchi on the (right side) of the earlier configuration, it would surely not be correct.

 

In fact, I wonder if the forks are WP? And that a spacer from Sport 1100/ 1100 Sport would be the solution?

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Here is the file I was trying to attach.  As it says -- two types of forks were available.  And this was one of the files from This Old Tractor.

 

LeMans front end.pdf

 

Anyway, the axle seems to tighten itself prior to the spacer on the right getting seated.  I can easily rotate that spacer and feel maybe 0.050" axial play. 

 

And this seems very strange compared to my other bikes with nuts on the left fork leg that draws the axle in until all the spacers are seated...

 

I put all the hardware back together right after the tire change, exactly the way it came out.  I did not check for play before taking off the front wheel, because I had no suspicion that anything was wonky.  

 

Oh, the bearings were not touched, other than the "feel" for bad bearings.

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Hey Stick,

Did you get your spacer issue sorted out?  If not and if you have the black Marzocchi fork I'd be happy to let you have a look at mine since I'm not far from you and I have an '02.

 

Tom

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