Collapsed front suspension or shock?

[JimmR75]

My adventures continue with a new-to-me 97 R1000RT with 78K on the clock that I purchased from a garage where it had languished for 10 years.  Other than the dormant period it was well cared for and cleaned up nicely. 

 

I went through it (all fluids including fuel, valve adjustment, BBS screw service, throttle body balance, brake fluid and pad service) and have put 300 miles on it over the past week.  

 

Got to work today (30 mile commute) and struggled to get it on the center stand as I always park my Airhead, RSL and this RT on the center stand.  Thought my hands were just cold from the ride (23 F) and put it on the side stand.  Came out 20 minutes later (after regaining full feeling in my fingers and thumbs ) to put it up on the center stand and could not, finally realizing that the bike was sitting lower than normal.  Quick check for flat tire, etc., revealed collapsed front suspension.  The shock is intact with no broken spring, intact mounts at top and bottom.  The telelever is intact as are the fork tubes. 

After carefully checking for any safety issues I rode it home (30 mile backroad 50mph commute) and it is in the garage.  

I watched the fork tubes while riding and they do move, so it is not a matter of a bent or bound tube.  The front suspension is just "collapsed".  I can pump it up and down while holding onto the bars, but just through a limited range of motion.  

 

Is the front shock pressurized or does only the spring provide lift support? 

Are the fork tubes just oil filled for lubrication or do they have a damping function?

Did I just blow out an old shock absorber or is there something else I need to consider or look for?

 

Thanks in advance for any input or assistance.  I have found this forum to be a spectacular reference.

 

 

[dirtrider]

27 minutes ago, JimmR75 said:

My adventures continue with a new-to-me 97 R1000RT with 78K on the clock that I purchased from a garage where it had languished for 10 years.  Other than the dormant period it was well cared for and cleaned up nicely. 

 

I went through it (all fluids including fuel, valve adjustment, BBS screw service, throttle body balance, brake fluid and pad service) and have put 300 miles on it over the past week.  

 

Got to work today (30 mile commute) and struggled to get it on the center stand as I always park my Airhead, RSL and this RT on the center stand.  Thought my hands were just cold from the ride (23 F) and put it on the side stand.  Came out 20 minutes later (after regaining full feeling in my fingers and thumbs ) to put it up on the center stand and could not, finally realizing that the bike was sitting lower than normal.  Quick check for flat tire, etc., revealed collapsed front suspension.  The shock is intact with no broken spring, intact mounts at top and bottom.  The telelever is intact as are the fork tubes. 

After carefully checking for any safety issues I rode it home (30 mile backroad 50mph commute) and it is in the garage.  

I watched the fork tubes while riding and they do move, so it is not a matter of a bent or bound tube.  The front suspension is just "collapsed".  I can pump it up and down while holding onto the bars, but just through a limited range of motion.  

 

Is the front shock pressurized or does only the spring provide lift support? 

Are the fork tubes just oil filled for lubrication or do they have a damping function?

Did I just blow out an old shock absorber or is there something else I need to consider or look for?

 

Thanks in advance for any input or assistance.  I have found this forum to be a spectacular reference.

 

 

 

Evening JimmR75

 

The forks have oil for lubrication 'only' as there is no springs or valves inside the front forks.

 

There is some pressure in the front strut but that doesn't add much to the bike's height (it is mostly spring pressure for suspension height).

 

See if you can look at the front strut as there is isolation rubber at the top & bottom, if that rubber has degraded & collapsed, or failed, then you will have a front height drop. Due to the strut geometry ratio it doesn't take much strut length change to lower the front end. 

 

 

[JimmR75]

Thanks very much, I tried to see if could get a look at that bushing but it is really up in there and not very accessible.  

 

Can the shock be removed without disassembling the rest of the front suspension?  

[Paul De]

Not saying this is the case as it makes not too much sense.  Wondering if there is moisture in the down tubes and sliders and it froze up while riding @ 23F.

 

might want to check the torque on the on the head crown blts.   23F ride to work sure sounds like they might be loose

[Michaelr11]

2 minutes ago, JimmR75 said:

Thanks very much, I tried to see if could get a look at that bushing but it is really up in there and not very accessible.  

 

Can the shock be removed without disassembling the rest of the front suspension?  

Yes.  You’ll have to get it up on the center stand, try rolling the bike tire or tires onto a piece of wood to raise the height. You will also have to take off the fairing panels and move the gas tank back a few inches to expose the top of the front shock.

[Corazon de Pollo]

It sounds a whole lot like the front shock has blown and it's now working on the spring alone.

Removing the front shock is rather time consuming due to the amount of stuff that needs to go off but otherwise not hard: I suggest getting hold of a shop manual to see if you feel like tackling the job.

 

[JimmR75]

I'll give a shot at removing the shock.  I can't determine anything with it installed.

[AndyS]

On 11/8/2019 at 11:21 PM, JimmR75 said:

...revealed collapsed front suspension.  The shock is intact with no broken spring, intact mounts at top and bottom.  The telelever is intact as are the fork tubes. 

After carefully checking for any safety issues I rode it home (30 mile backroad 50mph commute) and it is in the garage.  

I watched the fork tubes while riding and they do move, so it is not a matter of a bent or bound tube.  The front suspension is just "collapsed".  I can pump it up and down while holding onto the bars, but just through a limited range of motion.  .

 

 

 

Can  you explain what you mean by collapsed? you say you have movement there and then say it has collapsed.

The movement you do have there, is it a controlled movement or just a bouncy undamped movement?

When you are sat on the bike, does it feel 'nose down'?

Are you sure it is the front and not the back suspension causing issues? It is much more common for the rear end to cause issues.

[JimmR75]

I can pump the front end very slightly if I pump the bars vigorously.  I call the front collapsed because there is essentially no front suspension, maybe <1" at most.  I could see the fork tubes while I rode home and the suspension moved over a very limited range, but it did move. 

The movement is not "bouncy".  It is "weighted". 

The bike is definitely "nose down" whether I am on it or not.  It is far enough down that I have to roll the front wheel up onto boards to get the bike on the centerstand, which is how I always park my bikes.  

Rear suspension and final drive appear intact and feel normal. 

 

I also own a '95 R1100RSL so have some level of comparison, though it has aftermarket suspension.  

[AndyS]

Thanks JimmR75.

[dirtrider]

11 hours ago, JimmR75 said:

I can pump the front end very slightly if I pump the bars vigorously.  I call the front collapsed because there is essentially no front suspension, maybe <1" at most.  I could see the fork tubes while I rode home and the suspension moved over a very limited range, but it did move. 

The movement is not "bouncy".  It is "weighted". 

The bike is definitely "nose down" whether I am on it or not.  It is far enough down that I have to roll the front wheel up onto boards to get the bike on the centerstand, which is how I always park my bikes.  

Rear suspension and final drive appear intact and feel normal. 

 

I also own a '95 R1100RSL so have some level of comparison, though it has aftermarket suspension.  

 

Morning JimmR75

 

What color is the spring on your front strut? 

 

Any chance the last owner had shorter legs  so lowered the bike?  

[Lowndes]

JimmR75,

 

With the bike on the center stand and someone pushing down on the rear end and lifting the front wheel, how much extension of the front end do you get??  Does it extend fully or does it stay in the same range??  Can it be pulled down any further (you may have to put a support/jack under the engine for this)??

 

[Paul De]

If you left the house with it normal and is not now I am aligned to the suggestion by DR if the top or bottom spring retainers failed?

[JimmR75]

I am unable to see the top of the shock, even with a mirror.  I can see this on my RSL quite easily, but it has Ohlins on it and don't know how much different that makes.

 

I initially suspected a physical spring failure but the spring appears intact.  A failure of the upper keeper would potentially produce the degree of collapse that I am seeing, geometrically more probable than a rubber bushing failure.   

 

The RT is on the lift and I'll update the thread once I get it apart!

  

[JimmR75]

DR, sorry but I just realized that I missed your earlier question about the front shock.  The spring is black and "appears" to be stock.  I put ~300 miles on it before this issue developed and never had the impression that it had been lowered.  This suspension issue was a change and substantial, so I'm pretty confident that I will find some sort of failure and that this is not the result of any suspension modification.

 

The PO stated that he had parked it after he bought it in 2008 and put <2K miles on it because he felt it was too tall and heavy for him.  He never mentioned considering or doing any lowering mods.  I actually found the seat in the highest position and suspect that he was not aware of the adjustment capability or other features of the bike.  He was actually surprised when I explained that it was fuel injected after he stated that the "choke cable" appeared to be broken. 

 

He bought a GoldWing trike and this RT sat in his garage for nearly 10 years before I recently acquired it.  

 

Thanks again for everyone's input here.  Hope to dig into this over the weekend.

[Still CAL]

My 97 RT, Hard to see but just a shock:

[JimmR75]

Finally had a chance to dig into this problem, expecting to find a catastrophic failure of some sort. 

• Pulled the plastic and gas tank and removed the shock.  All appears normal and the spring, keeper and shaft are intact. 
• Disassembled the shock  (removed spring) and the shock will move through it's entire range, though with substantial resistance,  which may be normal since it is damping a 600+ pound bike. 
• Moved the front suspension through it's entire range of movement without any problems, binding or resistance (other than the weight of the front wheel) without the shock installed.
• Reassembled the shock and reinstalled.  
• I lose about half (~2.5") of original factory rated (4.7") front suspension travel once I take it off the centerstand (this is without the fuel tank installed, so will be more once I reassemble). 
• The remaining suspension travel is minimal at best.  
• I can now put it on the centerstand normally where I could not when this problem manifested itself.

The telelever, mounts, pivot, etc. are all intact and operate through their range of motion properly and smoothly without the front shock installed.  My guess at this point is that I have had some sort of internal failure in the shock itself that is either reducing it's load capacity, binding it intermittently at some point in it's travel, or some combination) on top of the fact that the stock suspension is 22 years old with 78K on it. 

 

I have owned a 95 R1100RSL for several years for comparison but it has Ohlins on it.  This RT is new to me (< 1 month and ~300 miles) and had sat in a garage for ~ 10 years before my recent purchase.  Whatever the issue is occurred after my purchase and during the most recent 30 mile commute.  

 

I'm new to this RT but have 50 years maintaining my own bikes, most of those offroad models, so have seen my share of suspension issues.  I keep circling back to the shock as the culprit as I have disassembled, inspected, measured and reassembled this front suspension with no startling discoveries.  

 

My plan right now is to purchase a replacement (used) shock and see what changes unless someone here has another suggestion.  I am aware of the risk of purchasing someone else's problem but am not interested in investing heavily in suspension.  

 

 

[dirtrider]

20 minutes ago, JimmR75 said:

Finally had a chance to dig into this problem, expecting to find a catastrophic failure of some sort. 

• Pulled the plastic and gas tank and removed the shock.  All appears normal and the spring, keeper and shaft are intact. 
• Disassembled the shock  (removed spring) and the shock will move through it's entire range, though with substantial resistance,  which may be normal since it is damping a 600+ pound bike. 
• Moved the front suspension through it's entire range of movement without any problems, binding or resistance (other than the weight of the front wheel) without the shock installed.
• Reassembled the shock and reinstalled.  
• I lose about half (~2.5") of original factory rated (4.7") front suspension travel once I take it off the centerstand (this is without the fuel tank installed, so will be more once I reassemble). 
• The remaining suspension travel is minimal at best.  
• I can now put it on the centerstand normally where I could not when this problem manifested itself.

The telelever, mounts, pivot, etc. are all intact and operate through their range of motion properly and smoothly without the front shock installed.  My guess at this point is that I have had some sort of internal failure in the shock itself that is either reducing it's load capacity, binding it intermittently at some point in it's travel, or some combination) on top of the fact that the stock suspension is 22 years old with 78K on it. 

 

I have owned a 95 R1100RSL for several years for comparison but it has Ohlins on it.  This RT is new to me (< 1 month and ~300 miles) and had sat in a garage for ~ 10 years before my recent purchase.  Whatever the issue is occurred after my purchase and during the most recent 30 mile commute.  

 

I'm new to this RT but have 50 years maintaining my own bikes, most of those offroad models, so have seen my share of suspension issues.  I keep circling back to the shock as the culprit as I have disassembled, inspected, measured and reassembled this front suspension with no startling discoveries.  

 

My plan right now is to purchase a replacement (used) shock and see what changes unless someone here has another suggestion.  I am aware of the risk of purchasing someone else's problem but am not interested in investing heavily in suspension.  

 

 

 

Afternoon JimmR75

 

If everything else checks out then it is pointing to either relaxed front spring or an incorrect front spring.

 

E-Bay front strut  would be a good "next test". Or make a spring spacer to add more load to your current  spring. 

[JimmR75]

DR, thanks very much for the reply.  I am at the same conclusion at this point.  

 

• Per my narrative, I find no issues with the structure, condition, movement or range of motion until I reinstall the shock.  
• I was unable to use the centerstand after this problem manifested until I removed, disassembled, reassembled and reinstalled the front shock.

 

My speculation at this point is an internal failure in the shock itself (possibly intermittent) combined with the spring condition that you suggest.

 

 

 

[Paul De]

wonder if there is a longitudinal crack in the spring coil. 

[dirtrider]

28 minutes ago, JimmR75 said:

DR, thanks very much for the reply.  I am at the same conclusion at this point.  

 

• Per my narrative, I find no issues with the structure, condition, movement or range of motion until I reinstall the shock.  
• I was unable to use the centerstand after this problem manifested until I removed, disassembled, reassembled and reinstalled the front shock.

 

My speculation at this point is an internal failure in the shock itself (possibly intermittent) combined with the spring condition that you suggest.

 

 

 

 

Afternoon JimmR75

 

Sometimes air in the front fork tubes can change the front height slightly. When the bike sits on the center stand for a while air can get into the fork tubes past the seals.  Then when back on the wheels that compressed air can add a bit of boost to the front height.

 

In cold weather, or after riding a while, that air can slowly escape. 

 

It doesn't make a lot of difference but  makes some difference in height. 

[dave_a]

Springs hold the bike up, shocks just slow the movement. The spring is junk, or the adjusting collar has gone over the adjusting tits on the shock body.

 

Basic rule of thumb is the suspension should compress 1/3 from full extension with rider(s) on the bike. Fine tune from there.

[BrianM]

I have a set of shocks off a 97 RT. I can send a picture if you are interested. ISTR they have about 50,000 miles.

 

Could have them for cost of shipping.

[JimmR75]

BrianM, thanks very much, that would be truly appreciated.  I am in zip 43074.  Let me know the most convenient way to proceed.

[BrianM]

Here is what I have. I am in WI, shipping should not be too bad to OH. I also have complete tear shock. Sent a PM.

[JimmR75]

First, thanks to all here for input, information and offers.  Several have offered replacement shocks for the cost of shipping, however I had already ordered one from eBay prior to the offers and installed it today.  

 

Problem solved as the RT rides normally again with the installation of the $10 eBay shock.  

 

I'll watch the classifieds for a set of aftermarket front and rear takeoffs but for now it is back on the road.

 

[AndyS]

Thanks for closing this off and reporting back with the good news.

[JimmR75]

I may have spoken too soon.  My commute this morning reveals a substantial "clunk" when the front end extends.  Visual inspection reveals nothing startling.  

 

I suspect that my $10 eBay front shock may have little if any rebound damping and the front end is "clunking" down when extended.

 

I commute 30 miles each way and will monitor this on the way home.

 

Stay tuned!

[JimmR75]

False alarm, story follows. 

 

The clunking continued on the ride home.  Got home and looked into the noise, starting at the bottom (axle, calipers) and worked my way up, looking up inside the fairing with the flashlight ...

 

... to see the horn hanging by the wires...  

 

... because the nut that mounts it to the bracket had disappeared ...

 

... allowing the horn to bounce intermittently off the top of the telelever...

 

... end of story.

[Lowndes]

Thanks for the finally!!

 

Safe travels.