Pre-load adjuster wouldn't turn and then.....

[marston_c]

I've got a 05 LT with only 18K miles and recently the spring preload adjuster ( OEM shock ) knob had been getting very difficult to turn by hand to the point that it started to strip out the recess in the knob which goes on the "bolt head" like pin that goes into the adjustment cylinder. Rather than ruin the knob I removed it and tried turning the adjustment in ( tighter ) with a 14mm socket. Everything went well infact it got easier as I went along. I put the knob back on and started to back it out and got half way through the adjustment range and all at once and completely on it's own the knob spun counter clockwise like I had a air rachet on it and the pin which moves in the adjustment cylinder had backed all the way out. It even had some of the soft cast metal from the adjustment cylinder in the threads. I have no hope of getting it to thread back in.....

I haven't seen any leaking fluid and I'm not sure why the it froze in the first place but I'm fairly certain it's ruined now. I'm looking for ideas on repair/replacement. I've read the other threads and my perception is that people who like a firmer sporty ride go with Ohlins and some others who want more adjustment and control over ride quality go with Wilber or Works. Maybe I'm off a bit. Anyway I want the ride quality and ability to go between 1 up and 2 up with luggage and keep a consistent ride comfort and feel either way. Thanks in advance for your time and feedback.

[cfell]

Bummer "first post", Marston...

I've modified these many times and didn't have anythining like this happen..

One thing you learned, tho... most things on this bike do not need to be "forced"... It sounds like the PO (Previous Owner) may have messed things up.

The way the "preload" adjuster works...is to push a piston down...and in that way you will push the oil into the rear shock... "preloading" it.

To "adjust", we normally
1- put the bike on the CS
2- back out the adjuster fully
3- then remove bolt holding the adjuster to the bracket...
4- Invert the adjuster...
5- note where the hose "banjo" lines up.. scribe the location if possible.
6- Now, clean things up..
7-Now, loosen the banjo bolt.
8- Insert the long end of a small screwdriver or allen wrench into the "adjuster hole"
9-press the plunger all the way in
10- Invert (banjo hole up) ADD oil (jack/hydraulic), to the adjuster until full
11- Keep adjuster inverted, re-attach the hose/banjo/bolt to the bottom of the adjuster.
12- turn adjuster right side up and reattach.

So, basically the adjuster is a cylinder with a plunger that the "knob" screws in and out.

If you remove the adjuster then disassemble, you may be able to clean and repair then re-oil

[GlennM86]

Went out last evening to try to follow the directions found throughout this forum to add oil to the OEM Shock Adjuster.

My problem is that the upright Shock Adjuster turns in both directions but nothing moves. It looks like it is sitting in the center of the adjustability. I turned it for a few minutes in both directions and no movement.

Thoughts?

[marston_c]

I disconnected the banjo as described and removed the adjuster from the bike. Now without any back pressure from the shock oil I'm able to see that most of the threads in the adjuster itself are destroyed and there isn't any hope of repairing it. I called the dealer and the adjuster is not offered as a separate part and the OEM shock is around 900 bucks same as after market.

Since I already spent my vacation money this year on helping to get our 1 mile long gravel driveway surface treated I thought I'd at least get to enjoy the bike this summer.... maybe a few weekend trips or something but this shock thing has really put me SOL.

OK, my pity party is over... sorry. Does anyone know where I may get this adjuster for the OEM shock? Maybe a wrecked bike or someone who upgraded to aftermarket. I'm gonna check online auction sites and the sort but I don't expect any luck. The bike only has 18,000 miles... I'd like to think I could get by until next year on the shock that's in it.

[rab1967]

Try here, http://www.beemerboneyard.com/

He is a member of the forum and sells used parts.

[cfell]

Try here, http://www.beemerboneyard.com/

He is a member of the forum and sells used parts.


Yeah.. as well as "LT Parts"... Now, another "option" I would try before "not" riding...

I would get new banjo washers then use a bolt with steel washers on both sides and "clamp" them together, effectively sealing the oil in the the tube. If it rides too stiff, take some oil OUT of the tube to provide some compressibility...

At least until you replace the fouled part.

[cfell]

Went out last evening to try to follow the directions found throughout this forum to add oil to the OEM Shock Adjuster.

My problem is that the upright Shock Adjuster turns in both directions but nothing moves. It looks like it is sitting in the center of the adjustability. I turned it for a few minutes in both directions and no movement.

Thoughts?

Glenn.. the plunger inside will NOT move.. you'll need to turn the adjuster to the loosest ... then put an allen wrench through the hole in the bottom and "depress" the piston... actually push it TOWARD the adjusting handle.

Now, try turning the knob .. to see if you can move the piston....

Now, if you're looking to replace the adjuster, there are bunches that have been removed during "upgrades" to other styles of shock... they may make them available to you.

[GlennM86]

Glenn.. the plunger inside will NOT move.. you'll need to turn the adjuster to the loosest ...


Deacon, therein lies my problem. Although the adjuster spins, it doesn't move up or down so I can't get to the "loosest" position.

I have been reading about stripped threads on the adjuster, missing detent bearing internally, etc.

It seems like the stripped threads would be the primary reason that the adjuster does not adjust up or down...just spins at the same level.

I have only 6K miles since April but I am sure that with 52K total miles it still has the original shocks. I am probably due for replacements anyway.

Looks like next tax rebate may be going to Ohlins...Hmmm?

[cfell]

Glenn... You can buy a couple of "adjusters" from some members here, I am sure.

Also, I admit I've never had the "adjuster" apart, but I wonder if it's repairable... maybe not via any BMW kit, but via your own resourcefullness. Maybe you can "rethread" by filling the threads with LOCTITE repair product.... maybe you can change the "screw" part... I don't know.

One thing I do know... not every part MUST be replaced. I wonder if you could work through it... There are some good engineers here and I'm guessing the problem can be "fixed" without "replacement"...

If anyone reads this and has an adjuster to commit to the project, I'd gladly try to figure out a solution...

[ArthurKnowles]

FWIW, while I've never seen just the adjuster for sale on eBay, I often see complete OEM rear shocks. I wouldn't be surprised if there is on up now.

[marston_c]

Nothing on eBay right now but I'll keep an eye out. beemerboneyard.com had the entire shock assembly for $105 but sold it. I have an email into them to let me know if they get another. If there's a "parts wanted" area on this site I'll try that too.

I may take cfell's advice and try topping off the banjo with shock oil and using a bolt and nut with copper break line type washers to see if I can make it ridable. I'll look into repair of the one I have and if I have any luck I'll certainly let everyone know.

[NOGILLS2]

Be sure to contact Tony @ LTParts.com (http://LTParts.com)

Check with him he may have the adjuster or the whole shock for a better price.

[GolfGuy]

I got to tell you...yesterday I did the fill reservoir thing.
You cannot believe the difference that made in my ride!! :D
If filling your reservoir does that much...can you imagine the difference a new shock would make! :dance:

[marston_c]

NOGILLS2 - thanks for the tip... I've sent Tony an email

I'm looking forward to new shocks myself but they aren't in the cards this year.

Update on "repair" of my damaged adjuster...

Yesterday I drilled out the two punch holes made on each side of the adjuster being careful to only drill deep enough and large enough insure the punched whole was no longer holding it. Then I used a grinder to carefully remove the lip which was pressed down to hold the center part of the adjuster ( part with the stripped threads ) into the tube. After removing the lip a few light taps popped it right out. The adjuster bolt pushes on the plunger inside but is not directly connected to it so the bolt and the stripped out piece of metal will come out separately. The actual part with the threads looks more like a really thick washer ( about 10mm - 12mm thick ) made out of soft metal which looks like aluminum or other soft metal so it's really not hard to imagine how it could strip in the first place.

This morning I'm headed out to get a replacement bolt ( larger ) for the plunger and 4 set screws which I plan on using to try to secure the newly threaded piece back into the adjuster tube along with matching taps and bits. Wish me luck.

Oh, one other thing... I thought about trying to just take the original plunger bolt out, drill and tap and then try to rinse shavings from the inside of the plunger thoroughly and insert new bolt in effort to avoid the drilling and grinding but the factory bolt has a collar of sorts made on to the end of it which presses on the plunger and also keeps the bolt from backing all the way out...... practical but unfortunate if you ever have to go through what I'm doing.

Hopefully my next post will be good news.... either that my fix worked or that I got a replacement plunger.

[ArthurKnowles]

I know you couldn't find one on eBay, but I found three for you ...

This search will show then all ...

http://search.ebay.com/K1200LT-K1200-LT-K-1200-LT-shock_W0QQcatrefZC6QQfposZ92028QQfromZR9QQfsooZ2QQfsopZ2QQfstypeZ1QQftrtZ1QQftrvZ1QQmppfqyZQ28K1200LTQ2cQ22K1200Q20LTQ22Q2cQ22KQ201200Q20LTQ22Q29Q20rearQ20shockQQmppfqyZQ28K1200LTQ2cQ22K1200Q20LTQ22Q2cQ22KQ201200Q20LTQ22Q29Q20rearQ20shockQQsabfmtsZ1QQsacatZQ2d1QQsaobfmtsZinsifQQsatitleZQ28K1200LTQ2cQ22K1200Q20LTQ22Q2cQ22KQ201200Q20LTQ22Q29Q20shockQQsspagenameZSTRKQ3aMEFSRCHXQ3aSRCH

Two were $149.95 and one was $199.99. They are actually in eBay stores if I remember correctly. If you fix doen't wotk, you may want to try one of them.

[marston_c]

I finished the "repair" of my adjuster and have ridden 70 miles or so and all seems ok. I guess the real test may be two-up riding.

Here's what I did:

- Scribe marks on the bottom of the adjuster so I could later reconnect the banjo ( fluid line ) in the same position.

- Remove adjuster and then using a small bit ( I'm guessing it was around 1/8th but use your judgement ) drill out the punched indentations on each side of the adjuster near the top keeping in mind to NOT drill too deep...

- Used a grinder to remove the top edge of the adjuster tube which had been machine pressed around the edges to hold the stripped out aluminum piece in... grinding off just enough to expose the seam between the tube and aluminum piece then used a little muscle to pull the aluminum piece out of the tube.

- Used 13/32 size drill bit to drill out the center of the aluminum piece removing the damaged threads and then used a 12mm x 1.50 tap to put new threads in and used a M12 x 1.50 x 45mm bolt to replace the OEM adjuster bolt.

- Put the aluminum piece back in the top of the adjuster tube and used a #25 drill bit to drill three new holes through the tube wall into the aluminum piece space about equal distance apart around the tube kinda forming a triangle. Have to be careful not to drill too deeply and damage the threads you just made or otherwise weaken the aluminum piece. I drilled about 1/4" deep... maybe a little more. Then I used a 10-24 tap to make threads in the three holes and used thread lock on 10-24 set screws in the three holes.

- after using compressed air to remove all metal shavings I flipped the adjuster tube upside down, filled it with Hydraulic Fluid/Jack Oil and then reattached the banjo in the original orientation using the scribe marks as reference.

** A few things to note **
You pretty much have to use a vice while drilling and grinding on this thing... be sure to use something to minimize the damage to the actual parts from the teeth on the vice like small thin strips of wood, etc.... and don't over tighten the vice because you could crush or bend the tube and then the whole thing is worthless.

Also, after removing the aluminum piece from the tube you'll see why the bolt would never come all the way out... it has a type of collar on the end of the bolt. Your replacement bolt isn't going to have anything that will keep it from backing all the way out and although the plunger inside the tube will stop at a certain point before damage to the plunger I would try not backing the bolt out too far.

It took me a few trips between stores looking for working bolt/tap & set screw/tap combinations. I originally wanted to use fine threads for the bolt but couldn't find a 12mm tap which had a 1.25 thread pitch. Maybe I was better off using a 1.50 because it's less likely to strip????

I'm still gonna buy a used shock assembly to have as a backup in case my repair fails.

[jzeiler]

Marston_c,


I admire your persistance on this repair, there are only a few of US that are crazy enough to attempt something like this. I recently went deep inside the hydrualic centerstand to fix a 0.030" O-ring that was leaking.
You might want to fill in your profile so we know where to go to get our adjusters fixed:) .