November 25, 2009
My bike is a 2007 DL-650 with 62,500 miles on it and I have not done any maintenance on the steering stem bearings to date.
I will answer some questions right up front:
“Does replacing the steering stem bearings, in my motorcycle, get rid of the infamous ‘clunk’?”
No, the clunk is still there. However, it is different sounding, and takes more force from a bump to initiate the clunk sound. What I believe is, my bike had two clunks that were “layered” on top of each other. One of those clunks was loose steering stem bearings. That part of my “clunk” is now gone. What is left is the “standard clunk”, found on nearly all DL-650s. I can tell you that my clunk is, NOT coming from the forward, fuel tank, hold down, bolt as some other DL-650 riders have discovered; or feel, that is where the clunk is on their bikes.
“Does replacing the steering stem bearings get rid of the wobble?”
Yes, it does. There is a hill near my home. Before I changed my steering stem bearings, if I rolled down the hill with no hands on the handlebars, (this is the standard deceleration setup), in a short time, I was near a “tank-slapper” situation. The tires that are currently on the bike are, a well worn Trailwing up front and a well worn Anakee on the rear. After changing the bearings, and riding on the same tires, just mentioned, the bike tracked perfectly, no handed, down my same “test hill”. There was absolutely no wobble.
One situation I did not test is, tightening up the OEM stem bearings. It is quite possible that, if I had tightened up the OEM stem bearings, the “deceleration wobble” would have disappeared in this case as well. But, because of the type of riding that I do, I had already decided to upgrade the OEM bearings to, tapered roller bearings. Taking care of the “wobble” was secondary.
When I started this project, I knew that I was going to end up having to make two tools to complete the job. Because of this, I chose to follow the sequence that I have written about below. By doing so, I “uncovered” the items that I needed to fashion the tools for, (stem nut removal tool, and a “bearing basher”). I have illustrated how I made the tools within the steps below.
The replacement/upgrade bearings I used were, All-Balls Steering Stem Bearing Kit 22-1003. I bought my kit from, http://www.amotostuff.com/product/22-1003.html
A final comment; It is important for readers, to understand that I have never done this type of work before. What is seen here, (in the photographs), is exactly what I am seeing for the very first time. I am no mechanic, let alone a motorcycle mechanic. I am just a fellow, who out of necessity, needs to do as much of the work on my bike as I can. I am also an individual who enjoys learning new things.
This topic is covered in the Suzuki Service Manual starting at page 7-26.
My first goal was to expose the steering stem nuts so that I could determine what kind of a tool I needed to fabricate to remove them. And, to also retighten them during reassembly. That meant, the first thing I needed to do was to remove the top forkclamp to be able to see the steering stem nuts.
The first thing I did was, park my bike, in gear, and on its sidestand. Then, I removed both the left, and the right cable/wire wickets from the front of the forkclamp.
Then, I removed the handlebar clamps. (I have SW-Motech® risers installed)
Once I removed the handlebars from the clamps, I used a bungee cord, wrapped around the front of the cowling, from one side of the handlebar to the other, to secure the handlebars forward out of my work area.
Next, I loosened both top, forkclamp bolts. (I didn’t remove them. I just loosened them.)
The top stem nut is 1 1/4″ in size. I found, it takes a good amount of muscle to loosen it. (This is why I kept the bike on its sidestand, and in gear. I figured I might “wrench” the bike off of its centerstand, if you used it instead of the sidestand.) However, I discovered it took too much effort, with a 1/2″ ratchet, to remove the top-nut. I ended up having to use my inexpensive impact wrench to do the job, ($25 impact wrench, hooked up to a $150 Lowe’s/Kobalt compressor.).
Theoretically, I should have been able to remove the top forkclamp at this point. But, I found that the left, and right, cable/front brake hose restraints prevented enough slack, in the front brake hose, and power cable, to be able to lift the forkclamp off of the stem.
I was able to work both the brake hose, and the power cable, around enough to remove the forkclamp. I have since removed the brake hose and the power cable from their restraints. I have wire-tied them to the outsides of the restraints instead of having them fetched up hard inside the restraints. This provides for easier removal in the future.
With the forkclamp removed, I could study the steering stem nuts, and make a decision as to what kind of tool I needed to fabricate, to remove, and to retighten, the stem nuts. I drove to my local Lowe’s and purchased a 6″ long x 1 1/4″dia steel nipple. They didn’t have any plain old steel, so I had to settle for the more expensive galvanized version. (An 8″ long nipple, would have been better to have had, when I was retightening the stem nuts. I would have had a little more clearance over the fuel tank to swing my pipe wrench handle.).
I cut the threads off of one end of the steel nipple. I then squared up my first cut because it stunk……
Then, I slipped the steel nipple over the stem and down on to the top stem nut. I marked two “teeth” on the pipe, that I needed to cut, that would align with two slots in the stem nut.
Using a hacksaw, I cut where I needed to; removing metal to create my “wrench”.
The inside diameter of the steel nipple was too small to allow the “teeth” to slip into the slots of the stem nut, so I had to bevel the teeth back a bit to let that happen.
Using a pipe wrench……
…..I spun the top stem nut off of the stem.
With the top steering stem, (locking), nut and washer removed, (JUST the top, locking nut is removed. I left the bottom nut in place.), with my homemade wrench, I knew that I could proceed with the job with a successful outcome.
EDIT: Since I originally did this job, I have modified the above wrench to have three “teeth”.
Next, I reached up under the cowling and wrapped my forktubes with masking tape to mark their clamped height in the triple tree. (The reason I did this is explained farther below.)
I loosened the axle pinch bolt.
Then, I loosened the front axle.
I removed the left and right allen screws, that hold the fender in place.
Next, I removed the left and right brake calipers.
I hung the brake calipers off of “hooks” from my crashbars. (I made the hooks out of sections of steel, coat hangers.).
Then, I removed the brake line junction/fender bolt. (On the right side, behind the forktube.).
The “specialized” nut fell out from inside the fender when I did this. It can only go back in one direction, so I didn’t worry. I also removed the brake line clamp bolt from the left side of the bike.
I removed the speedometer cable clamps behind the left forktube.
Then, I removed my “Superbrace®” forkbrace from the forktubes.
Next, I reached up inside the cowling and loosened the top bolts, of the bottom forkclamp.
Then, I raised the front wheel off of the ground. I used a floor jack, and a block of wood underneath my SW-Motech® skidplate.
I removed the front axle bolt. The front wheel dropped right out.
Now, I loosened the remaining two bottom forkclamp bolts. I did this one at a time, because I knew that the forktubes were going to slide right out and hit the floor if I wasn’t careful. The front fender, also dropped clear as well.
Then, I removed the brake hose clamp that is fastened to the front of the lower forkclamp.
It was time to start disassembling the stem head area. I could remove the bottom stem nut by hand it had gotten so loose!
I pulled off the bearing dust cover from the stem.
I supported the steering stem, underneath, with one hand, and I “wiggled/pushed” downward on the steering stem, from the top, with my other hand. The steering stem dropped free of the bike.
This is what the replacement/upgrade bearings look like. The outer race, that the bearing rides in, and the inner race, with the tapered, needle bearings, and their cage. The dust seals are on the floor. You can also see the steering stem and the top and bottom OEM bearings still on the stem.
I put the outer races, to the new bearings into my freezer. I heard that doing this can help during installation. The cold contracts the metal, to make the bearings a tad smaller; hence easier to install. (That’s my Danvier ice cream maker container waiting to be used…….)
This is a photo from the top looking down through the stem. The top and bottom OEM bearing races need to be removed. The top one is fairly clear in the photo. The bottom one is, that very thin, “silvery line” at the bottom of the stem tube.
I grabbed the closest tools on my bench……….
………and slid a mill file, handle first down through the tube until it came to rest on the top edge of the bottom OEM bearing race.
I tapped the file with a hammer; working my way around the top edge of the bearing race until it dropped out of the stem tube.
I did the same for the top OEM bearing race; by reaching up through the bottom of the stem tube…….
………..and tapping the file with my hammer until the top race popped free of the stem tube.
I grabbed one of the “frozen races” from my freezer, I spread a little grease into the bearing lip of the stem, and I pounded the race into the top of the stem opening by using a hammer and a 2″ pvc coupling.
I tried the same technique with the bottom race. I greased the race opening in the bottom of the stem…..
……..but the pvc coupling was too short. I couldn’t get enough swing with my hammer due to the cowlings being in the way.
So, I grabbed what was closest at hand, which was the top adaptor to my Harbor Freight tire changer, and I pounded the bottom race home.
I checked for gaps between both races and the stem with a mechanic’s mirror. There weren’t any.
Next, it was time to remove the bottom bearing race from the steering stem. It has been pressed on. On page 7-30 of the Suzuki Service Manual, they say to remove the race with a hammer and a chisel. They also show a diagram of doing this. I tried it too…..
……..and even tried to hammer/chisel/pry the race up. I was doing more damage to the forkclamp then I wanted to!
So, I grabbed my Dremel tool, and chucked a fiber wheel up, and cut several “kerfs” around the bearing race.
A couple of taps with the hammer and chisel and the bearing race freed itself, and slid right off.
I slid one of the new bearing seals down to the bottom of the stem. Then, I slid one of the new bearings down the stem as far as I could……….
……..it was now time for me to make the second “specialty tool”.
I drove to Home Depot and purchased a 12″ long x 1 1/4″dia steel nipple and an 1 1/4″ pipe cap.
I cut the threads off of one end of the 12″ steel nipple.
I cut several kerfs down the length of the pipe with my hacksaw; as deep as the frame of the hacksaw would let me go, (about 5″).
I refer to them as “fronds” as in, “palm fronds”.
I tightened a hose clamp around the fronds and tightened it to close the gaps between the “fronds”.
I slid the “bearing basher” down over the stem, until it made contact with the bearing. The “basher” can’t come in contact with the bearing cage, otherwise there was a risk of breaking the cage and sending the bearing needles tumbling about. So, by “trial and error”, I kept grinding the edges of the fronds to make them smaller, which resulted in a tighter fit around the stem; reducing the outside diameter of the “basher”.
This is what my “bearing basher” looks like. It is a tight fit around the stem, and the hose clamp is in place.
But, I discovered that the outside diameter was still too big. It touched the cage of the bearing. So, I ground a bevel around the outer edge of the “bearing basher”.
I “tuned” the bevel with a flat file, (the same one I used to remove the bearing races with……), and I also tuned the bottom edge of the basher where it came in contact with the inner bearing race during installation.
Once the “bearing basher” was fit and tuned, I screwed the pipe cap onto the top end and I pounded downward…..
…..to set the bearing.
Here are the two “specialty tools” that I needed to do the job. They cost less then $15.
Pretty cool, huh?
The horse smells the barn………it’s time to head home.
I greased up the bottom bearing. And, I greased up the bottom bearing race.
Next, I slid the steering stem up through the stem tube; slid a forktube up into the forkclamp of the steering stem; placed the bottom end of the forktube on top of a wooden block; and snugged up one of the forkclamp bolts. I took a rest…. The, I slid the other forktube up through the bottom forkclamp; resting the bottom of that forktube on top of the wooden block; and snugged up a forkclamp bolt on that forktube as well.
What I just described above looks like this:
I live alone. I work alone. I had to come up with a way to do what I needed to do. Another pair of hands would be helpful. But, I got creative with what I had on hand, to get the steering stem up into place, and to hold it there.
I greased up the new, top bearing, and also the race I installed previously in the top of the stem. I slid the new bearing over the top of the stem and down into the race.
It is here that I realized, I had to get the steering stem up higher in the stem tube. By adjusting the forktubes, in the forkclamps, along with the wooden block, I was able to achieve this.
I slid the remaining new dust seal down over the stem, and on to the top of the bearing.
Next, I slid the OEM dustcover into place.
I tightened the bottom stem nut to begin drawing the steering stem up into its final resting position and to “set” the bearings.
On page 7-30 of the Suzuki Service Manual, there is a procedure for, “Steering Tension Adjustment”. I have ridden this bike enough to know what I like. For me, the manual suggests a tension that is far too loose. This looseness is what causes the infamous “deceleration wobble”. However, if the bearings are too tight, I know that my motorcycle will “weave” at slow speeds. “Been there, done that”; with too loose, and too tight stem bearings!
This is how I wrapped up the job.
I slid both forktubes up through the lower forkclamps, until they came to the masking tape lines. I snugged up all four forkclamp bolts.
I slid the front fender into place and snugged up the two front fender bolts.
I mounted the front wheel and snugged the axle bolt.
I took pressure off of the floor jack and lowered the front wheel of the bike to the ground.
By doing this, it allowed me to tighten the bottom stem nut tighter and more easily. I was intentionally over-tightening the nut, but not destructively tight. To get the nut tight without the front wheel turning; responding to the pressure I was applying to it, I again grabbed what was closest at hand, and jammed a 2′ level between the front forks, and fetched up against my crashbars.
Next, I slid the top forkclamp over the forktubes, and removed the 2′ level from between the forks.
Using my hands, I grabbed a hold of the steering assembly and I racked it back and forth several times; “stop-to-stop”. I did this to help seat the bearings into their races.
I jacked the front of the bike back up so the front tire was free of the ground. I removed the top forkclamp and jammed the 2′ level back between the forktubes. I loosened the stem nut.
I experimented with loosening, and tightening, the stem nut until I had the feel that I wanted to the steering assembly. Suzuki recommends an initial force of 200 – 500 grams to start to turn the steering assembly. I adjusted the stem nut to where I wanted it; where it felt good to my hands. Suzuki recommends a torque value of 32.5 lb-ft. I don’t have a torque wrench to measure this with the tool I made. Like I said, I tightened the nut to the point where I felt the front end responding the way I wanted it to.
I slid the washer down over the stem.
Then, I threaded the stem lock-nut on to the stem and tightened it down. Suzuki recommends a torque value of 58.0 lb-ft for the steering stem lock-nut. Mine is as tight as I can get it with my “nut tool” and my pipe wrench. It’s not going to budge!
I slid the top forkclamp over the forktubes, and the steering stem, and I tightened the steering stem topnut.
I tightened, and torqued, all 6 forkclamp bolts; locking the forktubes in place.
From here, I “retraced” all of my disassembly steps, and reassembled my motorcycle, (“Pumping” the front brake calipers so that they would work properly once they were reinstalled!).
By upgrading my steering stem bearings, to tapered roller bearings, and by experimenting with different tensions on the new bearings, I have eliminated any “wobble”, at any speed, with any front tire, (New, or worn!), mounted on the rim.
Here is an example of that in the video below. Although not of a very good quality, I am riding off of the summit ofCadillacMountain, (Located onMount Desert Island,Maine), standing up on my footpegs, with no hands on my handlebars. I am following two automobiles, down the mountain, in a classic “deceleration wobble” situation. There is no wobble, and I have total control over my motorcycle.