700/750 Maxim-X Menu

Maxim-X Engine Guards (aka Case Guards)


Engine guards, more accurately referred to as Case Guards, are installed for several possible reasons. Predominently, they protect the engine casing and side covers from more devastating damage should the motorcycle fall over for any reason. However, engine guards are also used to mount highway pegs and just as often they're simply an aesthetic addition, something to improve the appearance of the motorcycle by adding chrome. Whatever your reasons for wanting them, you should know that engine guards for the Maxim-X aren't easy to find.

Strictly speaking, only one type of engine guard was designed to fit the Maxim-X (Fig. A). This commonly recognized style of Maxim-X engine guard also comes in a similar style with rounded corners but slightly different mounts (Fig. B). And finally, with a little adaptation, it's also possible to install VMax engine guards on a Maxim-X (Fig. C):

Figure A Figure B Figure C
Yamaha Part#: ABA-1AA31-00-00
Superseded Part#: 1AA-W0741-00-00
Yamaha Part#: ABA-5K531-00-00
Yamaha Part#: ABA-1FK31-00-00

Option #1:  ABA-1AA31-00-00
If you choose to install the standard factory guards (Fig. A) on your Maxim-X you won't have any trouble bolting them on. These are the guards that were designed specifically for the Maxim-X and the mounts fit the frame bolt pattern perfectly without any adjustment. The only difficulty you'll have is in finding a set. Yamaha discontinued production of these guards long ago so they're pretty scarce. The only place to find them these days is on eBay or similar services.

Option #2:  ABA-5K531-00-00
If you choose to install the guards with the rounded corners (Fig. B) you'll discover that only the right side guard bolts into place without difficulty. On the left side, there's an additional frame bolt that interferes slightly with the lower mounting flange. The standard factory guards (Fig. A) have a small step in the flange to clear the bolt (Fig. D below), but although the bolt pattern is identical on these guards (Fig. B), the straight flange needs to be bent a little to fit in place securely because it doesn't have the same step (Fig. E).

Figure D Figure E
Stepped
Straight

These guards have also been discontinued by Yamaha and are equally difficult to find these day.

Option #3:  ABA-1FK31-00-00
If you're like me and you aren't having any luck finding the standard factory guards for your Maxim-X and you don't like the look of the rounded ones, then you'll be happy to know that it's possible to adapt the standard VMax engine guards (Fig. C) to fit the Maxim-X with only a limited amount of basic fabrication.

As always, I've provided a complete history on how I converged on the means to adapt the VMax guards. If you're not interested in reading all the mundane details of the entire process, then you might want to skip directly to the end of this section where you'll find abbreviated instructions.

Figure F Figure G
Maxim-X Guards
VMax Guards

First, it's important to observe that the upper mounting flange is different on the VMax guards. While the Maxim-X flange (Fig. F) points down, the one on the VMax (Fig. G) points up. The orientation of the upper flange is downward on the factory Maxim-X guards in order to approach the mounting bolt from a side that doesn't interfere with another frame bolt. The first two images below show how the same two frame bolt positions compare to the two different flanges with each in place.

Figure H Figure I Figure J Figure K
Frame Bolts in Relation
to Maxim-X Guards
Frame Bolts in Relation
to VMax Guards
Spacing Collar (Blue)
to Offset Flange
Longer Bolt
with Collar

In order to get the VMax guards with their upward pointing flanges to bolt securely into place, it's necessary to install a 10mm spacing collar between the frame and the VMax guard flange (Fig. J). The spacing collar effectively offsets the upper flange far enough to clear the lower of the two frame bolts and makes it possible to torque the upper of the two bolts without distorting the flange (the upper frame bolt is the one which is used to mount the top flange of any of the engine guards) . However, installing a 10mm spacing collar also requires the installation of a longer bolt (Fig. K) because the original bolt no longer shows through on the other side of the frame and isn't long enough to fasten a nut to.

As you can see from the images above (Fig. F and Fig. G), the other end of the VMax guards (the bottom mounting flange) present additional problems. The bolt holes don't line up with any frame bolts and to complicate matters, the left side of the frame isn't the same as the right so it becomes necessary to fabricate something unique for each side. However, the good news is that fabrication isn't more complicated than creating a short adapter plate for the left side and a slightly longer plate for the right.

Of course before beginning any fabrication, it was necessary to choose an appropriate material. I knew corrosion would be a problem so I initially considered stainless steel. I knew I didn't need much material and also knew it could very likely be polished to a near-chrome finish, but finding something cost-effective wasn't so easy. The stainless steel I was able to find only came in large sizes of insufficient gauge and cost in excess of CAD$10. That was a lot more than I could justify for two small adapter plates so I continued looking for something appropriate and inexpensive.

I eventually converged on a galvanized 90° shelf brace. The material was available in a suitable gauge, it was sufficiently corrosion-resistant and shelf braces are cheap. I think I paid just about CAD$3 for the piece I needed. I chose a 6" (152mm) brace predominently because of the 4mm thickness and the 28mm width. Those were dimensions that I felt would word serve in both form and function.

Figure L

The width worked visually because it closely matched the bottom mount of the VMax guards and the thickness satisfied my need for sufficient bending resistance in the adapter plates.

Figure M


Having selected an appropriate material, it was then necessary to take some measurements. I started on the left side of the Maxim-X and attached the upper mount of the left VMax guard to its intended position then swung the lower mount back and forth until I found an appropriate position for it. That was decided, in part, by appearance but my main concern was to find the shortest possible distance from the hole in the bottom VMax guard mounting flange to an existing frame bolt position. The one which I thought would be most effective was the first bolt ahead of the engine mount bolt on the left side. I measured the distance as 35mm centre to centre. That became the measurement I used for the separation of the holes in my adapter plates.

I marked up the shelf brace then loaded a cutting wheel into my angle grinder and started cutting. I initially only held the shelf brace in-hand when I started cutting with the grinder - that turned out to be bad idea. The cutting wheel only had to get caught once before I decided it would be best to properly clamp the shelf brace into a vice. Luckily, I survived unscathed.and lived to tell about it :)

Figure N

I went on to fabricate two identical adapter plates and finished both before I realized that the frame bolt I had designed for on the left side of the Maxim-X didn't exist on the right. So, again, I attached the top mount of the right VMax guard to its intended position then aligned the bottom mount to achieve the shortest possible adapter plate and measured. In this case the adapter plate hole separation was to be 65mm, which would be almost double the 35mm hole separation on the right side. That was a little longer than I wanted but there wasn't much that could be changed so I went ahead. However, when I marked up the next piece of shelf bracing, I found that the existing holes in the brace were already 58mm centre to centre. I could have drilled a new hole precisely where I wanted it but, after considering the situation for a moment, I decided to use the existing holes. For structural reasons I preferred a shorter adapter plate anyway and the 7mm difference wasn't so overt that the right side guard would be noticeably out of alignment from the left. The obvious benefit was that it saved me the trouble of drilling any holes in the shelf bracing material so I went with the 7mm closer spacing.

I fabricated the right side adapter plate which, unlike the left, consisted of nothing more than cutting it to length and rounding the corners. Just for aesthetic reasons, I later also smoothed the edges and put on a couple of layers of paint to help protect against corrosion.

Sourcing the spacing collar (Fig. K - blue piece) wasn't especially easy. I had to rummage through some parts which my father had accumulated during his 35 years as an aircraft mechanic. Among them were high strength aluminum spacing collars with a height of 10mm, an outside diameter of 13mm and an inside diameter of 8mm - a perfect fit where I intended to use them. It's not likely that you'll find the very same collars but there are several other options. Some hardware suppliers sell collars of various sizes but if you can't find any, it's always possible to use an appropriately sized nut, a series of washers or even a section of pipe cut to length. However you accomplish the task, you should install some kind of spacer to offset the upper mounting flange of the VMax guards off the frame far enough to clear the interfering frame bolt. The following picture (Fig. O) clearly shows the left side guard in place with the spacing collar installed between the upper mounting flange and the frame.

Figure O

I initially thought I might be able to use the stock bolts for the upper mounts but with the added thickness of the mounting flange (4mm) together with the spacing collar (10mm), the stock bolt just became too short to use. I also thought I might be able to use the stock nut but when I was completely unable to source a matching metric bolt of ½" greater length, I opted to replace the respective frame bolts with equivalent imperial bolts of suitable length and matching nuts.

Of course, to attach the custom adapter plates to the lower mounting flanges of the engine guards two more bolts and some washers were needed. Below is a list of all the supplies I bought or acquired showing quantities, sizes and prices.

VMax Engine Guard Mounting Hardware Supplies
Item
Ref.
Size
Qty
Cost (ea.)
Shelf Brace, Galvanized 90°
Fig. L
6" x 1-1/8" x 5/64"
1
CAD $2.57
Bolt, Upper Mount
Fig. K
- *
2
- *
Bolt, Adapter Plate
-
- *
2
- *
Spacing Collar
Fig. K
13mm OD x 8mm ID x 10mm
2
CAD $0.00
Nut, Upper Mount Bolt
Fig. K
- *
2
- *
Nut, Adapter Plate Bolt
-
- *
2
- *
* I'll provide the missing sizes when I know what they are. Meanwhile, use something appropriate.

After the adpater plates have been prepared and the new parts have been supplied, bolt each VMax engine guard losely into place. Then, since there's inherently a little play in the assembly, position the guards to align the left to the right as closely as possible before torquing them into place. I also added a ½" Yamaha self-adhesive emblem to the outermost end of each guard just for an added touch. Of course, that's optional .


Abbreviated Intsructions:  Mounting VMax Guards on a Maxim-X

01) Buy one (1) 6" galvanized 90° shelf brace as in Fig. L
02) Cut a piece of shelf bracing as in Fig. M
03) Drill a hole in the piece just cut as in Fig. M
04) Cut another piece of shelf bracing as in Fig. N
05) Smooth edges of both adapter plate pieces (painting is optional)
06) Buy two (2) 10mm spacing collars as in Fig. K (perhaps nuts or washers will do)
07) Buy two (2) ½" longer upper mount frame bolts, nuts & washers as in Fig. K
08) Buy two (2) appropriate short bolts, nuts & washers for adapter to guard connections
09) Loosely bolt shorter adapter plate to first frame bolt ahead of left engine mount bolt
10) Loosely bolt longer adapter plate to engine mount bolt on right side
11) Remove original upper mount frame bolts completely
12) Attach VMax guards at upper mounts with new bolts, nuts & washers, with spacing collars between guards & frame
13) Loosely attach adapter plates to existing holes in left & right guards with new bolts, nuts & washers
14) Align engine guards and tighten all mounting bolts & nuts


That's all there is to it. This was designed to be done by anyone, for little cost, using easily sourced parts and with only minimal tools. I hope it served its purpose. Good luck.