BMW R1200RT FRONT SHOCK REPLACEMENT
CONTINUED FROM PART 1
Authors
Here's the picture of the Rear Ohlin shocks preload adjuster with the modified placement.
Note the spacer between the captive nut on the backside of the exhaust hanger which moves the adjusters bracket back toward the tire, clearing the backside of the saddlebag.
O.K. then on to the front shock.
First I sprayed my favorite penetrant on the top shock nut and let it soak for awhile.....
I originally removed the tank bolts and moved it back while keeping the hoses and wires connected, then I decided to just take it off making more room and giving me a view of all the stuff underneath for cleaning, etc. I guess the job could be done with the tank installed as there is still room to remove the front shock. I used a 1/2 drive air wrench and a 15mm deep socket to spin the nut off. You could also hold the piston shaft with an allen key and use a wrench to loosen the nut....BUT....that's tough, and there's a good chance it won't budge!!! Here's where air tools are worth their weight in gold.
Unplug the connection of the wiring for the front shock (ESA only) and remove the harness from any straps on the frame, etc. Here's what the plug looks like. It's up top in front of the tank.
The next step is optional. The installation instructions with the Ohlin shock states to remove the bolt holding the front brake lines to the frame at it junction. But I didn't bother to read the instructions BEFORE doing the job (I know, it's a guy thing..) and I had no problems with the brake lines being long enough once the front end is extended. BUT...they were very tight, so if this concerns you, please feel free to loosen the lines from the frame.
Here's the picture of the connection point.
NOTE: I HAD TO LATER REMOVE THE FRONT SHOCK BECAUSE OF A LEAK AND I COULDN'T GET ENOUGH CLEARANCE WITHOUT REMOVING THIS BRACKET. I realized that I had the bike on a piece of plywood under the centerstand when doing this original swap so it let the back tire drop farther then when I tried later, without the wood under the stand. Just a FYI.
Break the bottom mounting bolt loose from the right side of the bike with a T50 socket and extension but don't remove the bolt yet.
Now, with the bike still on the centerstand, position a floor jack under the engine in the front (I used the center of the exhaust headers cross pipe). Carefully jack the front of the engine until the front "forks" extend fully but the tire is still touching the ground. Now you should be able to wiggle the front end slightly and remove the bottom bolt. BUT, if you find that there still isn't enough room on either side to remove the shock because of the alternator cover, just remove it. I had another alternator belt I wanted to install so it was a good time to remove the cover.
The alternator cover is held on by 4 small torx screws- T25 and T23?..
Here's a picture of the screws..
And the cover being removed. Just lower it down.
Good time to check the belt and clean everything in there.
BTW- my belt looked like new (30.5K mi.) so I left it alone. PLUS it looks like the top pulley needs to come off to remove the belt as there's no adjustment on the alternator support. Looks like a job for another time. ANOTHER NOTE: LEARNED LATER THAT THE BELT IS PRIED OFF AND ON BY ROTATING THE ENGINE. I'VE CHECKED THE BELT AGAIN AT 40K AND IT STILL LOOKS NEW----SO I'LL WAIT FOR ANOTHER DAY....AGAIN!
Now with everything out of the way, the shock can come out from the left side.
Here's a blurry picture of the removal.
The old shock and new Ohlins shock.
Note: the included spanner wrench for preload adjustment.
Slide the Ohlins up and reuse the aluminum bushing and rubber washers from the old shock. Install the top washer and nut and either tighten it with the air wrench (like I did) or find the torque figures and find a way to hold the end of the piston rod (it's got flat sides) and torque the nut!! I did go back and checked that the nut was tight while holding the rod with an adjustable wrench. Next move the engine up or down slightly while sliding the bolt in from the right and tighten it with a T50 socket. Torque if need be.
I've left the preload adjustment where it was as delievered. There seems to be plenty of room the make adjustments with the tool as seen in the above photo, but once the bodywork is replaced...it's going to be a bear to adjust.
See my notes below about riding impressions and adjustments.
Now all that needed to do is the reinstall the tank and bodywork!!! I found it was easiset (well, it's not really easy)...to start at the back of the bike and work forward from the top to the bottom, ending at the headlight area.
Be warned!!!---I have 2 torx screws left over and I've doubled checked the complete bike for missing ones, and I'll be darned if I can find where they go!!! I put them in the glove box, figuring they must go underneath the panels somewhere and can't be that important, as nothings loose or rattling!
Good luck.
RIDING IMPRESSIONS-
I've only had two solo rides and one two-up session since the install so I'm still in the process of evaluating the results. But the first thing that was apparent was the lack of damping left in the ESA's- (why I made the switch in the first place). With the stock units, no matter where I set the damping- Comfort, Normal, or Sport made no difference, the bike still wallowed through turns; especially with my passenger! Now the rebound is controlled with a firm action. Riding 2-up required a few complete turns of the preload knob to keep the pegs from touching down in fast corners- Note that I have the peg lowering kit so I tend to scrape the feelers quite a bit anyway (I'm debating removing them). I added a few more turns until we were able to ride briskly through our favorite twisties with out sparks. I added rebound damping with each preload increase.
I don't have exact numbers of turns, clicks to report yet, as I haven't taken the time to mark the preload adjuster some how to keep track, but I'll be working on that shortly.
I describe the ride as FIRM, yet COMFORTABLE.
The front-
The front-
I've left the front preload as delivered and am so far happy with it. I did make a couple of clicks in the rebound.
A note about the rebound clicks (there is NO compression adjustment)- the manual states 16 click total from 0" which is full CW=SLOW. But like other Ohlin shocks I've worked with there is actually more like 30 click out until the knob just spins free and has no clicks left. This isn't a concern to me because I believe that the taper of the needle in the rebound circuit is such that only the first 16 make any difference. Just something to be aware of and may be a question for Dan Kyle at some point.
I have yet to set sag, although I did take the time to put a wire tie around both piston shafts to check their total travel, and both shocks are using all the available travel but I don't feel any solid bottoming.
The rear spring is very beefy as there is very little piston travel availible as delievered.
I'll need to spend more time playing with the adjustments and riding before I can report here on any changes.
For now, I am happy with the improvement. Stay tuned for more......
Steve
UPDATE: I've had a chance to set the SOLO RIDER SAG for the front and rear.
NOTE: The readings are obtained by taking SAG MEASUREMENTS and Adjusting Preload, which I'll assume the reader knows how to do! A great guide to these techniques is: Sportbike Suspension Tuning by Andrew Trevitt.
REAR RIDER SAG- The sag was checked without the bags attached, as they were in the way while taking measurements. First I started with the preload adjuster backed off so there was no tension on the spring, you'll be able to feel the difference in the tension of the knob. Next, I marked the preload adjuster knob with a dot of yellow paint and used black paint on the gold body of the adjuster to indicate a starting point. With both dots aligned the preload is FULL SOFT or "0". (This was the position of the preload when I received the shock and is what I have been using as a SOLO setting). Set here, the FREE SAG (weight of bike only) is 5mm- which tells me that the spring rate is spot on! The free sag should ideally be between 5mm and 10mm. As a quick check of this, you should be able to just lift up on the rear of the bike and feel a small amount of movement. The RIDER SAG (me seated on the machine with full gear) is 32mm. As a general rule, rear sag is best between 30mm to 35mm for the street and 25mm to 30mm for the track.....remember YMMV!. This is where I'll leave the preload for solo riding. Oh, BTW- write all this stuff down and keep it handy for future reference.
Now, for the heck of it, I decided to check the FULL FIRM preload position. I turned the knob CW as far as it would go, counting the turns and came up with 20-1/4 turns until it stopped. Measuring the distance from the spring collar to the bottom of the hydraulic adjuster on the shock showed that the spring was compressed an extra 6mm from the factory setting, the range of spring preload for this shock. With the preload set here I could barely reach the ground with my toes when seated. The FREE SAG was "0mm" meaning the spring was "topped out" -and - RIDER SAG was 3mm. I could hardly compress the spring while pushing down from the rear at the luggage rack! I haven't had time to check the TWO UP-LOADED SAG yet, but I don't think it will be anywhere near this point. Stay tuned..
Next, I reset the preload back to the FULL SOFT position.
REBOUND- It's best to start at the full SLOW position- knob turned CW until seated- then count the clicks out from here (Ohlins recommendation also). I can usually get in the ballpark by standing to the rear of the bike, lifting it off the centerstand, then pushing down and releasing to judge the rebound "speed". I settled on 12 clicks out (of a total of 16- see note above).
FRONT RIDER SAG- Here, I'll give a quick measuring guide that may be useful if you have no assistant. Put a zip tie around the left "sliding tube" and slide it down to the boot, this will be the guide. Next sit on the bike (with gear) while its positioned close to a bench or similar solid object that can be used to lightly support yourself while the bike is upright. Gently dismount and let the bike rest on the sidestand. Next lift the bike onto the centerstand, taking care not to put any weigh forward on the front wheel. Find a piece of lumber (2X4 works well) about 8 inches or so, and while lifting the front of the bike with your upper back from under the headlight fairing slide the board under the left side exhaust pipe near the bend, as the front tire leaves the ground. Turn the front end to the right and using a tape measure take the UNLOADED reading from the sliding tube's boot to the zip tie. Viola- quick and easy.
OK, then- SOLO SAG (with bags attached)= 45mm.
Note about front sag numbers. There seems to be no hard and fast numbers anymore like there used to be, because front forks have changed internally and the BMW's front end is, well, different, to say the least! The 45mm reading I got seems to work well and because the spring preload in the front is a bear to change--would love to have a remote adjuster---I left it alone. As long as there is no less than 30mm there'll be no danger of the shick topping out on acceleration.
REBOUND- I've settled on 16 clicks out which is FULL SOFT (according to Ohlins specs) and after a brief highway ride it seems to be great. It's easy enough to change though....
Well they you have it.
So far, I couldn't be happier with the set up and look forward to setting and recording the DUAL SAG preload and damping soon.
Stay tuned.....
O.K.- I'm back from a couple of longer tours with a passenger and luggage and can now report on the "loaded" sag numbers, preload and damping settings that worked for us.
I was able to set the rear "loaded" (rider, passenger, and bags) sag number to 35mm by turning the adjuster to the full firm position- this is 20 turns CW from the "0" position used for the solo rider setting. This setting supplied good ground clearance, even over rough roads fully loaded and we only touched the pegs once while hitting a good size dip in the road while cornering. I only felt the rear bottom out once during a 800 mile "fast paced" two up ride! Note: the rear shock has very little travel as delievered with the spring preload set by Dan Kyle Racing.
Speaking of DKR, he did an excellent job of spring selection and preload settings for the weights and riding style I told him. He mentioned that I would be using all of the rear preload when two -up, and he was right on the nose!!
It's best to have a discussion with him about these things and to be honest with your weights---(trust me, it was a touchy subject with the G.F.!)
Rear Damping- Two-up: I started with a setting of 9 clicks out from full slow and eventually settled on 7. No wallowing through turns and silky smooth on the highway. My passenger reported a nice, comfortable ride.
And, if anyone is interested, I'm using Michelin Pilot Road 2's set at F-36psi R-42psi for fully loaded riding.
Well there you have it.....I'm very happy with the purchase and set up of the Ohlins and highly recommend the change. Hopefully we'll have many more miles of controlled "twisties" ahead of us.
Steve
YET ANOTHER NOTE: I HAD TO REMOVE THE FRONT SHOCK TO SEND TO DAN KYLE FOR A REBUILD AFTER APPROX. 9K MILES BECAUSE THE SEAL WAS LEAKING!!
I highly recommend Dan Kyle for purchase and repairs--he took the shock back and rebuilt it with quick turn-around time--NO CHARGE--that's customer service!!
Comments
BMW
I don't think I would do this myself. I'm very picky when it comes to my BMW. I think I'd only use a BMW service, for any BMW repair. I think I could do it by myself, but I'm not as skilled as you and wouldn't really trust myself or very many others. http://www.eurobahnmotorsportsnc.com <-these guys are the only ones I would use for my BMW. I found them in NC. Do wonders.Jerry Kane - Feb 9, 2012
I just installed new Ohlins on my 2007 R1200RT and ended up with the following figures for sag, solo with all my gear. Front 52mm and rear 33mm, and that's with the rear adjustment all the way out. I am 160 lbs. and find solo the suspension barely moves and is very hard on my back. Even with my wife on who is 120lbs. I only turn it in one click ( not sure how many turns that was) but I have five clicks from all the way out to all the way in. I was hoping for a ride as plush as stock with more control but so far doesn't work for me.
Grant Oakes - Jul 12, 2011
Something's up here. My rear Ohlins has 20 total full turns from Soft to Firm. (see above).
Steve Methia - Jul 12, 2011
Steve Methia - Jul 12, 2011
I got my shocks from David Behrend at Fast Bike Industries as per Ohlins USA recommendations. Yes we discussed our weights and told him I didn't want it too firm. Right now it is firmer than when set on 2 up on my previous ESA setup. Clicks I was referring too was on the hydraulic preload adjustment, I went out and checked it and it has a click every full turn with a total of 5 full turns from fully out to fully in. I also set the rebound at 16 clicks out. The front shock has 8mm of preload and the rear has 16mm of preload.
I have put a call in to David and waiting to see what he says. I certainly don't want it any stiffer than stock before as it is too hard on my body. It felt good with both my wife and I on it and the preload turned in on full turn or one click.
Dean
Grant Oakes - Feb 16, 2011
I have put a call in to David and waiting to see what he says. I certainly don't want it any stiffer than stock before as it is too hard on my body. It felt good with both my wife and I on it and the preload turned in on full turn or one click.
Dean
Grant Oakes - Feb 16, 2011
rideaway,
thanks for the comment.
couple things- did you get your shocks from Dan Kyle? Did you have a discussion with the supplier about your weights and the type of riding you expect to do? You may very well have the incorrect (too firm) rear spring rate. Remember, preload only changes the ride height of the bike- it has no bearing at all on the "spring rate". This is a common misconception. It's important to start with a spring rate that gets you in the ballpark with sag numbers.
When you talk about "clicks" I assume you mean damping settings, which again are useless without the correct sag. I noted that the rear Ohlins for the RT has a very small preload adjustment range (6mm) and a pretty small total piston stroke before bottoming...so, it's important to have the correct rate spring before going forward!!
It may be best to give Dan Kyle Racing a call--he's very helpful.
Good luck,
Let me know how you make out,
Steve
Steve Methia - Feb 16, 2011
thanks for the comment.
couple things- did you get your shocks from Dan Kyle? Did you have a discussion with the supplier about your weights and the type of riding you expect to do? You may very well have the incorrect (too firm) rear spring rate. Remember, preload only changes the ride height of the bike- it has no bearing at all on the "spring rate". This is a common misconception. It's important to start with a spring rate that gets you in the ballpark with sag numbers.
When you talk about "clicks" I assume you mean damping settings, which again are useless without the correct sag. I noted that the rear Ohlins for the RT has a very small preload adjustment range (6mm) and a pretty small total piston stroke before bottoming...so, it's important to have the correct rate spring before going forward!!
It may be best to give Dan Kyle Racing a call--he's very helpful.
Good luck,
Let me know how you make out,
Steve
Steve Methia - Feb 16, 2011
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