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Discussion Starter · #1 ·
Hi all,
Checked my steering damper per Clymers. I found the front end of the damper body would move from side to side for maybe an inch and a half. This appeared to be play in the fork brace ball joint/bearing. Clymers indicates that in this case the fork brace must be replaced. Before I buy a replacement brace, I thought I'd check here for any other repair options.
Thanks,
Ken Davis
Mobile, AL
2002 LT
 

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Were you checking it because you think you have an issue with it? I think many people are running around with their dampers void of oil and never know it.

Just read through the part you describe in Clymer. Have you removed the damper yet or made sure the torx screw is not lose? It is an expensive part. I would be looking for one used and maybe replace the ball joint while replacing it. Another option and I am just thinking off the top of my head is to see if the spherical bearing is the same size as the one at the other end and possibly find a used damper and take them to a machine shop and see if they can remove them and swap them to replace the bad one in the fork bridge. It had to go on somehow.
 
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Discussion Starter · #3 ·
Were you checking it because you think you have an issue with it? I think many people are running around with their dampers void of oil and never know it.

Just read through the part you describe in Clymer. Have you removed the damper yet or made sure the torx screw is not lose? It is an expensive part. I would be looking for one used and maybe replace the ball joint while replacing it. Another option and I am just thinking off the top of my head is to see if the spherical bearing is the same size as the one at the other end and possibly find a used damper and take them to a machine shop and see if they can remove them and swap them to replace the bad one in the fork bridge. It had to go on somehow.
Gordon,
Yes, I have been doing some maintenance on the bike before we take a trip in April. I knew the damper had no damping action and the tried the Clymers test.
No, I haven't checked the torx screw, but I'll do that this week.
Thanks for the reply,
Ken
 

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2005 K1200LT
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The Clymer is not real clear. The side to side movement 1 to 1.5 inches is normal but up an down should be very little movement at all. The biggest check is to raise the front wheel and move the bars slowly then rapidly from side to side. You should notice a difference with resistance to the fast movement.
 

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The Clymer is not real clear. The side to side movement 1 to 1.5 inches is normal but up an down should be very little movement at all. The biggest check is to raise the front wheel and move the bars slowly then rapidly from side to side. You should notice a difference with resistance to the fast movement.
Thanks John. I have not messed with my damper yet but I have ordered seals to do a rebuild, maybe before May. I would think that there would be some rotational movement as the spherical bearing would allow but direct horizontal movement without any rotation of the damper would indicate a bad spherical bearing.
 

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northern Illinois bmw had a video on how to maintain this....I need to check rebuild mine...
 

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Discussion Starter · #7 ·
The Clymer is not real clear. The side to side movement 1 to 1.5 inches is normal but up an down should be very little movement at all. The biggest check is to raise the front wheel and move the bars slowly then rapidly from side to side. You should notice a difference with resistance to the fast movement.
John,
There is very little up and down movement in the damper. The bearing in the fork bridge might be OK. Definitely no resistance when the handlebars are moved rapidly from side to side. A damper rebuild is in my future.
Thanks,
Ken
 

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Discussion Starter · #8 ·
Thanks John. I have not messed with my damper yet but I have ordered seals to do a rebuild, maybe before May. I would think that there would be some rotational movement as the spherical bearing would allow but direct horizontal movement without any rotation of the damper would indicate a bad spherical bearing.
Gordon,
Where did you find the seals. Do they have a pressure rating greater than 10 psi? All the seals I have found on the internet have a 10 psi pressure rating.
Now that read your reply to John, maybe the spherical bearing in my fork bridge is bad. I think I'll look for a used fork bridge.
Thanks,
Ken
 

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Gordon,
Where did you find the seals. Do they have a pressure rating greater than 10 psi? All the seals I have found on the internet have a 10 psi pressure rating.
Now that read your reply to John, maybe the spherical bearing in my fork bridge is bad. I think I'll look for a used fork bridge.
Thanks,
Ken
I don't know about the pressure rating of the seals I have. I wasn't aware there was a requirement so I will read up on it more. I am sure John can give more information on the seal requirements as he has rebuilt a few as I recall.

Just went out and inspected my damper and I see the horizontal movement but it is movement associated with rotation of the damper bearing and not slop left to right so as you move the end of the damper shaft left and right with the wheel all the way to the left, you can see the ball in the bridge simply rotating within the normal movement allowed by the ball in its socket. I do have some up and down also but close inspection shows it is not movement up and down of the ball in its socket but more rotational movement of the ball on the second bearing on the end of the shaft. I can see how this can be confusing if you don't look at both closely. Looks like a place to occasionally try and grease though.

So, as John said, look at the ball in the bridge when you do the up and down check, If there is significant movement of the ball in relation to the bridge, then there is wear. It sounds as if you are OK though. If it isn't rattling around ball in the socket, I would just work on a rebuild.

Hopefully John can give us some more info on the seals. Here is what I ordered but if it is not suitable, I will order something else.

https://www.amazon.com/gp/product/B00MW7DRYU/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
 

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Discussion Starter · #10 ·
I don't know about the pressure rating of the seals I have. I wasn't aware there was a requirement so I will read up on it more. I am sure John can give more information on the seal requirements as he has rebuilt a few as I recall.

Just went out and inspected my damper and I see the horizontal movement but it is movement associated with rotation of the damper bearing and not slop left to right so as you move the end of the damper shaft left and right with the wheel all the way to the left, you can see the ball in the bridge simply rotating within the normal movement allowed by the ball in its socket. I do have some up and down also but close inspection shows it is not movement up and down of the ball in its socket but more rotational movement of the ball on the second bearing on the end of the shaft. I can see how this can be confusing if you don't look at both closely. Looks like a place to occasionally try and grease though.

So, as John said, look at the ball in the bridge when you do the up and down check, If there is significant movement of the ball in relation to the bridge, then there is wear. It sounds as if you are OK though. If it isn't rattling around ball in the socket, I would just work on a rebuild.

Hopefully John can give us some more info on the seals. Here is what I ordered but if it is not suitable, I will order something else.

https://www.amazon.com/gp/product/B00MW7DRYU/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Good advice, Gordon.

Thanks,
Ken
 

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Discussion Starter · #12 ·
Hi all,

I have the steering damper apart and will replace the seals. Most of the seals I've found in the correct 10x20x7 size for the steering damper are the typical seal used in a rotating environment, like a gearbox seal. Are these type seals adequate for the steering damper, or should a hydraulic seal be used? Hydraulic seals seem to cost more and I don't want to pay more if a hydraulic seal is overkill.

The original problem I had with the front end of the damper flopping from side to side seems to have been caused by a missing "cushioning" ring, like the two at the rear end of the damper. And, when I removed the damper from the bike, those two rings broke into several pieces. So, need to replace those three rings, too.

I've read that about 20cc of 5W fork oil is the correct volume and weight of oil to use. I think the thought is that some air needs to be left in the damper to provide a cushion to prevent a hydraulic shock effect in the event of rapid handlebar movement. Comments?

One last question. Is there any need to remove the screw at the front end of the damper rod? Mine is "frozen" and I'm afraid to put too much vise pressure on the rod at the risk of collapsing it.

Thanks,
Ken
 

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I think that screw is addressed in the disassembly instructions in the link posted in the link above.
 

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Discussion Starter · #14 ·
I think that screw is addressed in the disassembly instructions in the link posted in the link above.
Thanks, Beech. The write-up did mention using a hydraulic seal. Also, the screw on the end of the rod needs to come out.
Ken
 

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Hi all,

I have the steering damper apart and will replace the seals. Most of the seals I've found in the correct 10x20x7 size for the steering damper are the typical seal used in a rotating environment, like a gearbox seal. Are these type seals adequate for the steering damper, or should a hydraulic seal be used? Hydraulic seals seem to cost more and I don't want to pay more if a hydraulic seal is overkill.

The original problem I had with the front end of the damper flopping from side to side seems to have been caused by a missing "cushioning" ring, like the two at the rear end of the damper. And, when I removed the damper from the bike, those two rings broke into several pieces. So, need to replace those three rings, too.

I've read that about 20cc of 5W fork oil is the correct volume and weight of oil to use. I think the thought is that some air needs to be left in the damper to provide a cushion to prevent a hydraulic shock effect in the event of rapid handlebar movement. Comments?

One last question. Is there any need to remove the screw at the front end of the damper rod? Mine is "frozen" and I'm afraid to put too much vise pressure on the rod at the risk of collapsing it.

Thanks,
Ken
I filled mine up according to the video and haven't had any issue. I also replaced those rubber rings with parts I found at an auto parts store. I believe they were brake parts and long enough I could cut two or three rings from each one. Nothing fancy or special about their purpose and much cheaper.
 

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I filled mine up according to the video and haven't had any issue. I also replaced those rubber rings with parts I found at an auto parts store. I believe they were brake parts and long enough I could cut two or three rings from each one. Nothing fancy or special about their purpose and much cheaper.
Maybe, maybe not. Most materials that are compatible with conventional brake fluid (DOT 3,4,5.1) are not very compatible with petroleum oils. And materials compatible with petroleum aren't very compatible with brake fluid. Best case is your homemade seals shrink and leak. Worst case is they swell and make the steering get stiff.
 

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Maybe, maybe not. Most materials that are compatible with conventional brake fluid (DOT 3,4,5.1) are not very compatible with petroleum oils. And materials compatible with petroleum aren't very compatible with brake fluid. Best case is your homemade seals shrink and leak. Worst case is they swell and make the steering get stiff.
I think I wasn't clear on what I replaced. I did not replace the seals in my damper, only the fluid. If I did replace the seals they would be the appropriate type otherwise they would fail prematurely for the reasons you stated. The rings I was referring to are the rubber bushings (31 42 7 677 987 RING - 12,5X24X6,5 ) on either side of the damper mount points. They are only there to keep the damper from flopping around and keep some of the road junk out of the connection. I found a rubber bushing at the auto parts store that was longer but had similar ID and OD. I cut it into 2-3 pieces to replace the old dried out broken ones. I also used the same cut down bushings on the shifter linkage joints.
 

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I think I wasn't clear on what I replaced. I did not replace the seals in my damper, only the fluid. If I did replace the seals they would be the appropriate type otherwise they would fail prematurely for the reasons you stated. The rings I was referring to are the rubber bushings (31 42 7 677 987 RING - 12,5X24X6,5 ) on either side of the damper mount points. They are only there to keep the damper from flopping around and keep some of the road junk out of the connection. I found a rubber bushing at the auto parts store that was longer but had similar ID and OD. I cut it into 2-3 pieces to replace the old dried out broken ones. I also used the same cut down bushings on the shifter linkage joints.
Good deal.
 
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