On replacing the seat cover of my 1981 Honda CM400 Custom

I'm trying to be as good to my motorcycle as it has been to me.  With a Clymer manual and tentative self-confidence in aid, I'm motivated to tackle the art of motorcycle maintenance and repair.  After starting to ride, I realized my general geekiness does not include a natural intuition for engines and mechanics.  So I'm starting small.  My first successful diy: an oil change, with material and advice from Tallahassee Powersports.  Next task: repairing my torn seat, which was allowing rain and humidity to soak into, deform, and mold the underlying foam.

The seat foam, although imperfect, was still firm and seemed reusable.  So I decided to just exchange the manufacturer vinyl cover with a new, fitted one.  (Another option suggested online is to buy a sheet of vinyl and fit it yourself.  If needed, you can also buy shaped and unshaped foam.)  I bought a Saddlemen SaddleSkin seat cover at JCWhitney.com for 50 bucks.  Luckily, it appears that the fitted covers are available for most motorcycle years and models.  "Designed to fit with original factory seat, SaddleSkins(TM) are made with premium grade weather-resistant vinyl, and double stitched for quality and durability."  Standard shipping was quick and the product looked well made coming out of the box.  It was nice to see that there was a bit of padding under the rider and passenger sections.


There are two installation methods for the SaddleSkin: quick and full.  With the quick installation, you tighten the cover to the seat with the attached drawstring instead of securing it to the seat base.  This should only be a temporary setup, as it may allow the cover to move and crease, making wear and tear more likely.  The full installation is detailed below.  The only tools really used were a flathead screwdriver and flat-nose pliers.

First, remove the entire seat from the motorcycle.  This can be done by pulling back the latches on both sides of the motorcycle under the seat, freeing the back of the seat to be lifted up.  The right side latch can be seen in the middle of the image on the left.  Then pull back (there is a lip in the front of the seat that slides onto the bike).

Now start the cover removal process.  Look at the underside of the seat base.  The chrome edging detail can be removed by straightening its eight bolts so they are perpendicular to the rim (as seen in the below left image) and then prying up the (speed?) washers.  Save these washers.  Make note of the locations of the eight bolts - you will need to make holes at these locations in the new cover when putting the edging back on.  Pry apart the edging and the bolts should slide out.  The seat cover can then be removed by prying up every triangular hook on the inside rim (careful - they're sharp!).  See the below right image.

The foam was a bit damp, so I let it dry out for a day.  I then slid the new cover over the foam, making sure edges and grooves of the vinyl matched up to the edges and grooves of the foam.  It was a very, very tight fit, with the trim of the seat barely able to fold under the seat base rim.  The damage to the foam had cause it to widen too much, so I took off the cover and cut out a thin, long piece of foam along each side.  When I put the cover back on, it was still a very tight fit, but with some compression to the foam, it was apparent that the cover could definitely be attached to the inside rim.  Since the fit was already extremely snug, I did not have to worry about gluing the seat in place or smoothing out wrinkles.

The most difficult part of the process was hooking the trim of the new seat cover to the seat base.  Start by securing the front and back of the cover, and then work the sides.  Make sure the vinyl is as taut and symmetric as possible before pushing the edge of the vinyl onto the triangular hooks and clamping the hooks back down (you may want pliers for that).  I ensured the drawstring was clamped under the hooks for a more secure attachment.  Mark the locations of the holes for the chrome edging bolts on the new cover.  A friend may need to help you compress the foam and pull the vinyl for the last of the hook attachments because the cover will already be stretched extremely tight.  Keep in mind that warmed vinyl stretches better.

Almost done.  Create holes in the cover where the bolts for the chrome edging need to go.  You can see how I chose to do it in the image to the right.  Place the chrome detail where it should go on the seat and line up the bolts.  Push them through the holes and they should go through inside rim of the seat base.  Firmly push the speed washers all the way back down the bolts and bend the bolts down against the inside rim (the pliers helped with this).  The edging detail should be firmly down against the seat.  The seat is complete.  Just slide that front lip onto the bike and push the back end down so the latches click.

This whole process was very satisfying and seat looks great.  I recommend this process to anyone who needs a cheap, simple motorcycle seat restoration and has a foam base in good shape.

Hmm, I wonder if I'm now ready to tackle a master cylinder rebuild kit?