This document describes how Mike Wolf and I have installed Dzus 1/4 turn fasteners on our Ducati ST bikes (Wolfie's ST2sps project bike and my ST4). Our installation is based on Mike West's installation in England. Mike West is a member of the Yahoo! Groups Ducati ST list, and he has written up an excellent guide which we have used as a template for our efforts.  You can read about Mike's installation at:

Our installations are different from Mike West's in that neither of us has glued any receptacles.  In our solutions, we have used clip-on receptacles exclusively.

Anyone who has ever worked on his or her Ducati ST motorcycle, knows what a pain it is to remove the fairing. It is strange that to change the oil, service the battery easily, or perform any engine related routine maintenance, the headlight fairing and the mirrors must be removed.  This is a function of the poorly designed fairings, which necessitates the removal of the headlight fairing before the mid fairings can be removed.  Hey you Ducati engineers in Italy, I hope you are taking notes!

On their Super bikes (748/9*6/998), Ducati offers 1/4 turn quick release fasteners. I have them on my Ducati 748. The first time I had to remove the stock fasteners on my ST4, I knew that they had to go. I used Mike West's write-up as the basis for my conversion (thanks Mike). It was great to have Mike's write-up and parts list to look at. I understood what Mike had done. Since he had the fasteners on his bike already, I knew that the parts were going to work and I could at least duplicate most of Mike's setup, with the exception of the glued fasteners.  For some reason or another I did not want to glue any receptacles. To be honest with you, I do not know why, I just didn't. Now that I have done the conversion, I am not sure which is better glueless or with glue (more on that later). I exchanged emails with Mike few times before I ordered any parts. Mike told me that he has installed his Dzus Fasteners 6000 miles ago. Since his installation only one of the fasteners that he has glued had come off. That remark by Mike made me want to do the conversion without the glue, even more. Using Mike West's parts list, I started doing a little research to figure out what was involved.  The following is what happened next.

A 1/4 turn fastener is a fastener that only requires 1/4 of a turn (90 degrees) to go from fully unlocked position to fully locked position. It works on a principle of using a stud that has two 45-degree grooves on the outer perimeter of the stud. These grooves move in a spiral shape around the outside of the stud from the tip toward the head of the stud. The two spiral grooves toward the end of their travel, lose their slope and become perpendicular to the sides of the stud. At the end of each groove there is a slightly recessed half circle countersink bucket. Once the stud is inserted into a receptacle, two protrusions (pins) from the receptacle ride in the 45-degree grooves. After the pins move up the spiral grooves, they fall into the countersink buckets. It takes 90 degrees or 1/4 of a turn of the stud for the pins to travel along the grooves to reach the countersink buckets and lock, hence the name "1/4 Turn Fasteners".

Since at that the end of the their travel, the grooves are perpendicular to the sides of the stud and the countersinks are partially recessed, the pins on the receptacle act as a spring wanting to go back to where they were at rest. The pins cannot slide out unless a force is exerted to push them out of the pocket and back into the grooves.

Since the 1/4 turn of the stud goes from complete unlock position to lock position, the length of the stud is critical for proper fit and operation of the fastener. The thickness of the pieces that the stud goes through (holds together) plus the type of the receptacle that is used for the application determine the length of the stud.

I do not understand why Ducati has designed the ST fairing the way they have done it. The right side fairing and the front Ram Air fairing are attached to the plastic radiator reservoir. The reservoir is made of two injected molded plastic pieces that are either heat or sonic welded together. The dimensional tolerances of this operation are not great. Additionally I made multiple thickness measurements on different fairing pieces. There is a large variation in the thickness of the different fairing panels where the stock fasteners are mounted on the fairing.

The stock ST fasteners are typical screws and rubber wellnuts. On my bike where the rubber wellnuts are attached on the fairing, majority of the holes are fairly large. I guess large holes and rubber wellnuts can provide some give and therefore additional tolerance, if the fairing pieces do not go well together. A rubber wellnut is soft and fairly flexible. Once it is placed in a relatively larger hole, It can provide some X and Y mounting tolerance or give. Depending on how much one turns the screw into the wellnut, there is also some Z dimensional give when putting the fairing pieces together.

In order to fully remove each screw one needs to turn the screw close to 15 full rotations. As you can imagine due to the number of stock fasteners used on the Ducati ST fairing, the removal of the fairing can take a significant amount of time. Additionally it is very easy to "over torque" the screws into the wellnuts during the tightening of the screws. If this happens, the nut strips from the rubber and starts rotating within the rubber piece. It is very difficult to remove the stripped wellnut from the fairing when that happens.

I love the shape, and look of the ST fairing. Once installed, the fairing does a great job in providing wind and noise protection. Somehow, when the designers gave the engineers the drawings, the fastening of the fairing to the bike was completely overlooked. More than likely some kid who had never worked on a bike was responsible for coming up with a solution of how to mount the fairing on the bike.

Since the rubber wellnuts can provide a lot of play and give, how the fairing panels come together is not critical and does not have to meet a tight tolerance (cheap but not elegant solution). But on the other hand, when I work on my bike, the last thing that I want to do is to spend 20 minutes or more to just remove fairing pieces so that I can get started.

Having experienced the 1/4 fasteners on my 748, I could not wait to replace the stock fasteners.

I am not sure if Dzus is originally from United States or United Kingdom (U.K.)! I have a feeling that they are originally from U.K.

They are two Web Sites that represent Dzus:

The US site now refers to itself as "DFCI Solutions Inc.". When I started, DFCI was carrying the Panex line. Just visiting their site recently, they do not carry that line anymore. Anyway I tried contacting DFCI Solution and their distributors in California. I do not want to go through what I went through with them. To put it mildly, I was extremely disappointed on how they dealt with me, in particular with their sales and customer service or lack thereof. They never treated me as a customer. I was trying to get pricing information and to determine how I could place an order. I always felt that I was a thorn in their side and they just wanted to get me out of their radar screen. They were giving me "200 part minimum" ordering clauses and 16 to 18 weeks delivery dates. After wasting more than three weeks with DFCI and their distributors (WESCO Aircraft) and not getting anywhere, I ended up contacting Dzus UK. Due to some US distribution rights issues, Dzus UK could not sell the fasteners to me directly. But Dzus UK was great. After describing my situation with DFCI, they put me in contact with "Just Fasteners" in Scotland!

Since we were basically using Mike West's parts list, we ordered both 4mm and 6mm studs. Additionally, Wolfie and I ordered some different receptacles to see if we could eliminate the gluing. I think it is important to note that different people will use different mounting options. It is not a bad idea for people to order some spare parts. Especially the receptacles which are fairly cheap. This will allow people to experiment with different setup options.

Here is a comparison of what our part lists looks like:

Note: This is an actual parts list and does not include any spare parts. I strongly recommend you order spares for every part.

The 4mm Ringhead fasteners (long and short) are used to attach:

1) Upper and lower side fairing pieces to each other.

2) The side fairing pieces to the frame and radiator reservoir.

3) The side fairing pieces to the headlight fairing.

4) The side fairing pieces to the front Ram Air.

The 6mm Ringhead fasteners (long and short) are used to attach:

1) The left and right side fairings to each other under the bike.

Wolfie and I also purchased some 4mm L Bracket receptacles (Part number 334-310-190) with the anticipation that we eventually might be able to modify the upper side fairing panels to eliminate the need to remove the front headlight fairing to work on the bike. Our goal is to cut off some of the angle mounting plastic pieces (mounted to the reservoir on one side and the frame on the other side) and replace them with the L bracket. We will need to add two new holes to the headlight fairing and upper side fairing panels. This will eliminate the need to remove the headlight fairing to access the side fairing mounting studs (possible future project).

We also purchased some extra 6mm fasteners and different receptacles (336-100-300, 336-400-190, 336-300-190) to possibly modify the mirror mounts on our bikes to use the Dzus fasteners.

While the fairings are still on the bike, I recommend attaching a strip of scotch tape to the fairing next to the existing screws but on the panel that will hold the receptacles. Using a pencil, mark exactly where the center location of each screw is on the mating panel. This will help to make sure that the receptacles are installed exactly where they should, when the fairing is perfectly mounted on the bike. I found out that on my bike the existing holes that hold the wellnuts are fairly large. Because of the "give" that the wellnuts provide, when the fairing is properly installed on the bike, the screws may not be perfectly centered in the holes. The scotch tape can be easily removed from the fairing with no ill effect.

To remove an old or compressed wellnut, I inserted a small Allen wrench from the backside until the head of the Allen wrench was inside the nut. I tilted the Allen wrench until the rubber was decompressed on one side, I then moved the Allen wrench around until the whole rubber piece was decompressed. In some cases I ended up squeezing the compressed side walls using my fingers. I peeled the front piece of the wellnut that was compressed against the other panel. Holding the wellnut from the backside, I then pulled the whole wellnut out of the hole.

I was actually surprised on how many of the wellnuts on my bike were over torqued. Almost 60% of the wellnuts were showing signs of the actual "metal nut" separating from the rubber.

The lower part of the Radiator Cowl, is not symmetric! Don't ask me why, because I do not know. I actually made some measurements with a caliper to prove to myself that I was not going crazy. Since I wanted to rivet my receptacles and I also wanted the D-Ring of the fasteners to be at a special orientation after they were in the lock position, I assembled the fairing pieces on the bench to get the parts line up the way I wanted them. I then marked the outline of the rivet receptacles on the Radiator Cowl so that I knew exactly how to mount the rivet plates. This was a pain but I got it to work!

Since the Radiator Cowl mounting area is not symmetric and the holes are too far away from the edge, the clip-on receptacles cannot be mounted without some kind of modifications to the lower part of the cowl. Using a bench grinder, Wolfie cut-off the extra material to use the clip-ons. I have to admit, I like Wolfie's method the best. I will not consider gluing receptacles in this area, it gets too dirty and the lower part of the cowl is partially curved.

The following pictures show my rivet mounting and Wolfie's clip-on approach.