Friday, December 4, 2020

Motorcycle Wheel Alignment


I just aligned the wheels on a new motorcycle I just acquired. This is one of those activities that is an arcane procedure.
Back in the 1990's I made a post to the Ducati mailing list describing this procedure. And then I posted it on my blog back in 2012. But I keep seeing confusion about how to do this properly, so this is a refresh of that description, now with pictures!

A couple notes to begin:

  • For this to work, your motorcycle needs to be in good condition and undamaged (no warped wheels, bent swing arms or loose bearings that allow the wheels or steering head to wobble).
  • This method ignores how the chain and sprockets are aligned, and focuses on how the wheels and tires are aligned. I can imagine that having the sprockets and wheels be perfectly aligned simultaneously may not be possible, and I'd rather have the wheels lined up.

The "Thread Method" or 'String Method":
I've always aligned my wheels the way I saw Rich Oliver do it on his TZ250 years ago. I think this way is standard "racer" practice. 

You really should use a thread to do this. It is possible to use a string or something else thicker than a thread, but it doesn't work as well. The thicker the string, the harder it is to see if the string is bending around the wheel instead of just touching it. This will make more sense when you understand the procedure.

The theory of this procedure is that you run two perfectly straight parallel lines forward along each side of the bike. These lines are arranged to touch the edges of the rear tire. Then if the front tire is narrower than the rear tire, the front tire should be perfectly centered between these lines. Like this:

(image credit: Scott DiRoma - see the end of this post for more great info)

Put bike on service stand. Take about 15 feet of thread or string (elastic thread works best!). Tape center of thread to back of the rear wheel about 4" off the ground.

In the picture above, I have wrapped the thread around the wheel, taped it, and then run the end forward the front of the bike. Note how the lower thread that runs forward runs over the top of the tread block: it is NOT in the notch of the tread. It is important that the thread runs over the outer edge of the tread.

Bring the ends of the thread to the front of the bike. Tie the ends of the thread to some movable objects (I use a pair of jack stands), at the same height (about 4"). 

Make sure the thread is as high as possible without hitting anything under the bike. It must not hit anything like the exhaust or side stand.

The idea is to set the threads so they are parallel and "just" in contact to the front edge rear tire by moving the jack stands. 

This is where using a thin thread really helps. Above you can see the thread is just barely in contact with the front edge of the rear wheel. If it more than just touches, the thread will bend around the wheel and will no longer be running straight forward. Check this very carefully!

With the threads taped to the back of the rear tire, and "just" touching the front edge of the rear tire, they should make two parallel lines that run forward, passing along either side of the front tire. 

 It is hard to see the threads in this picture, but they are there. Make sure the front wheel is pointed perfectly forward by adjusting it carefully at the handlebar. The thread should be the same distance from the wheel at both the front and back edges of the tire.

Now the alignment of the front and rear wheels can be easily observed by examining the clearance of the front wheel and the thread on either side. 

 Above, you can see the right side of the tire (on the left in this photo) is is 23mm from the thread.

Here, above, you can see the left side of the bike (on the right in this photo) is about 15mm from the thread. So this front wheel is not perfectly aligned!

Again, be sure the front wheel is pointed directly forward with these measurements the same at the front edge and rear edge of the front tire. Also, be sure the thread hasn't fallen into the tread on the rear tire and is just barely touching at the front edge of the rear tire.

Adjust the chain adjuster appropriately if necessary, and then recheck. After you move the chain adjusters, you will have to recheck how the thread runs and touches the rear wheel and you WILL have to move the jack stands because you have moved the rear wheel!

 It's a pain to do the first time, but then it gets easy. Use the thinnest, elastic thread you can find. Also, try rotating the rear wheel to several points to make sure you aren't just adjusting for uneven tire manufacture. And make sure the thread isn't on some bump of "mold seam" rubber or in a tread at the edge of the tire. This would screw up everything.  

When using this procedure on my '92 750SS, a quarter turn of one of the chain adjusters is quite significant. When complete, the adjusters appear to be at even marks at either side of the bike, indicating adequate swing arm manufacturing. However, a quarter turn seems to effect the alignment significantly, but is just about invisible in relation to the adjuster marks. Doing this procedure properly will result in much better alignment than just counting on the adjuster marks.

There is ONE video on youtube that I have found that explains this well. Be sure to check it out here, by Scott DiRoma:

Wednesday, October 7, 2020

Husqvarna Adventure and Road Forum:


There didn't seem to be a good Husqvarna Adventure and Road forum... until this one! If you have a Husqvarna Vitpilen, Svartpilen or Norden, Check it out.

Wednesday, September 30, 2020

KiWAV Magazi CleaverII Mirrors and Wono Turn Signals on my 2020 Husqvarna Svartpilen 401

Here are a few pictures of my 2020 Husqvarana Svartpilen 401 with the KiWAV Magazi CleaverII Mirrors and Wono Sequential LED Turn Signals.

Note that you will need an LED Flasher Relay so that the LEDs do not blink too quickly. (Also note that the stock relay is attached to a short cable pigtail. You need to remove the relay AND the pigtail so that the new LED relay will fit. Also note you need to change the pinout of the connector. There is a good description here on

 The KiWAV Magazi CleaverII mirrors weighed 345g each, compared to the stock mirrors that were 342g. They also have an "aspheric convex lens". Note the vertical line in the mirror: the mirror is fairly flat inside of that line, but on the outside it curves away more rapidly. This can help you to see further out to the side of the motorcycle.

2020 Husqvarna Svartpilen / Vitpilen 401 Fender Delete - Tail Tidy - License Plate Mount

The Vintage Veloce custom license plate mount.

The original ugly and heavy "possum catcher" plate mount and fender.

The tail section of the 2020 Husqvarna Svartpilen and Vitpilen 401 is different from the earlier years. 
At the moment, there are few commercial "Fender Delete" or "Tail Tidy" kits available for the 2020 models. These kits typically consist of a license plate mount and sometimes turn signal mounts. I think the turn signal mounts on the 2020 bikes are fine, so...
So I decided to make my own aluminum license plate mount.

It is important to be aware that it is possible to place the license plate in a location where it will interfere with the rear tire. You must position it high enough that the tire will not hit the plate even when the suspension is fully compressed. Make sure there is more than 150mm of clearance between the tire and mount, plate, bolts, etc.
Below are some basic instructions for making one of these. Dimensions are shown in the photographs below!

The following tools are necessary.
  • jig saw with the proper blade for cutting metal
  • a guide for making straight cuts with the jig saw (I used a small steel carpenter square.) 
  • power drill 
  • small hand held "pin" drill (something like this.)
  • files and emery (wet/dry) sanding paper
  • various wrenches, hex drivers and other common tools
I used a small 6061 aluminum sheet for the project. It is important to get 6061, as it is stiffer than 3003.
It's also important to get 0.063 thickness, as the thinner stuff will also be too flexible. (It would be quite possible to make this from steel or another type of aluminum, this was just my choice.)

 I purchased the following parts at my local hardware store. You could definitely choose different size fasteners and paint.

  • 3 x stainless steel M5-0.80 x 12mm bolts (might want a bit longer depending on height of nyloc nuts)
  • 3 x three nyloc nuts (regular nuts will vibrate loose)
  • 6 x stainless steel flat washers to fit (I used SAE sized washers instead of metric as they had a bigger outside diameter.)
  • flat black spray paint
  • small zip ties for wiring
I like to use nylon license plate fasteners:
And this is the license plate frame I chose:
I also bought this LED light to illuminate the license plate:

First I made a cardboard mockup and taped it to the bike.

It looked good to me, so I transferred the outline to the aluminum sheet.

And then I carefully cut the sheet to shape with my jigsaw WITH THE PROPER METAL CUTTING BLADE. Also see in the picture how I used a carpenter's square as a guide so that I could cute nice straight lines.

Here is a picture of the cardboard mockup and the cut aluminum part.

The dimensions are clearly marked in this picture.

I then marked out the four holes for the license plate. The locations for these holes is different is other states and countries. (California dimensions shown further down.) You can do this with a hand drill if you are careful.

I then picked an appropriately size socket and marked nice curves on the corners. I clamped the piece down and used a file to sand down the corners to match the curve. I used a heavy file for shaping and then a finer file to smooth the edges all around the piece.

Here are the locations for a California motorcycle plate, marked in inches. Many other states use these same dimensions. Also note that I have marked the "bend line" 3 cm from the license plate area.

You must be careful if you want a sharp bend in the aluminum. I clamped it right at the edge of my workmate table and then a used board to apply pressure right at the bend line.

Here is how I placed the board, but I did use two hands on both sides and I was careful to apply most of the pressure right at the edge of the table at the bend line. I bent the plate to about 30 degrees.

Now it was time to mark the drill holes. Since the piece is bolted to the the fender, these holes MUST be place in exactly the correct locations. There are all sorts of electronics and brackets under the motorcycle seat that can get in the way, so I picked these locations carefully.

Next I removed the battery and then the fuse holder and the seat latch bolts. You don't have to remove the fuse holder or seat latch but you will need to move them out of the way when drilling!

Under the seat, beneath the seat latch, there is a bolt that holds the tail light in place. See the red arrow.

Directly in front of that bolt, there is a circular molding mark on the fender. See it in the picture below. I then drilled through the center of the circular molding mark from above. This is the center rear mounting hole for the license plate mount.

Then I held the license plate mount up against the underside of the fender using that first rear hole to align everything, and I marked the other holes with a pen. (Note the plate holder is flat and there is a slight curve to the underside of the fender. When you tighten the bolts the mount will curve up against the fender.)  I made sure everything was straight and then I used a needle drill to mark the centers of the holes.

Next I pulled the fuse holder out of the way and drilled the holes for the mount from above. Drilling from above reduces any risk of power drilling into anything important. (I did consider removing the rear wheel and drilling from below, but I prefer this method.) You can see it was necessary to pull the fuse holder up and forward.

Here are the completed holes. If you ever choose to remove the plate holder, you can easily plug these holes.

After test fitting the plate mount and then taking it back off (do that!), I prepared the mount for painting. I hand sanded it while wearing gloves (to avoid getting any sweat on the piece that might disturb the paint.)

And then I spray painted it flat black. I let it dry a full 24 hours and the last 6 hours were in the hot sun.


Now you need to remove the existing license plate mount / hugger fender / possum catcher, or whatever you call that thing. I'm not going to detail that but it is described in the manual. You do have to remove the plate holder from the actual fender to disconnect the wires for the license plate light! 

And you must remove the chain guard and take it apart because the wire runs inside of that. It's kind of a pain, but I carefully pulled the wire out all the way back up the right side of the frame. This requires the removal of several zip ties and you should replace these.
Here I am holding the wire and you can see it goes under the frame tube and into a zip tie. 

Here I am pointing to the connector that this wire goes to.

This is how I routed the wire and you can see I have zip tied it to a cable bundle under the seat.

I brought the wire to the battery area, and coiled the extra here before running the end to the new LED plate light (more on that later.)

I weighted this assembly, and it weighs 2546g! That is more than 5.5 pounds! All that weight is hanging off the back of the swingarm; that cannot be good.

Now to install the new plate mount! Put the bolts up through from the bottom of the fender. Be sure to use washers on both sides of the assembly, under the fender and under the seat. Getting the nut on the rear bolt is the hardest. I used a bit of duct tape on a small stick to hold the nut.

I then placed the washer used my stick to start the nut on the bolt.

The other two nuts were easily placed after lifting the fuse holder up and forward.

Here is how I attached the new LED plate light. I just used the double sided tape that came with it to stick it to the underside of the tail light. I did this at night so I could see if I like how it worked and place it as I desired for the best illumination. The LED's inside the unit's housing are not perfectly centered, so I chose to line up the actual LEDs with the center of the plate. (Note, the tail light alone does illuminate the license plate, but is is a red light and that isn't proper. This white LED fixes that.)

Now you just need to replace the seat latch bolts and the fuse holder. Be aware the fuse holder has a snorkel attached to it that goes into the air box. (I'm pointing to that below.) You need to carefully place the snorkel back into it's  hole to be able to properly replace the fuse holder. IMPORTANT: The other end of the snorkel is under the fuse holder and open. Make sure the wiring under the fuse holder does not block the open end of the snorkel!

Finally, MAKE SURE THERE IS ENOUGH CLEARANCE BETWEEN YOUR REAR TIRE AND THE PLATE HOLDER. I RECOMMEND MORE THAN 150mm. (Husqvarna specs shows the bike having 150mm of rear wheel travel.)

And here are some pictures of the installed plate holder!

And with the license plate installed:

Showing the LED plate light attached under the tail lamp. Works fine!