700/750 Maxim-X Menu

Maxim-X Coil Moisture Shield

Every Maxim-X owner knows that both the XJ700X and XJ750X have ignition problems in wet weather. If you've read the comments about Wet Ignition Coils in the Notes section of this web site, you'll know that ignition problems are often the result of coil housing cracks which, when wet or moist, facilitate arcing and allow moisture to penetrate the coils.

I had so many ignition problems that I was eventually forced to do something, anything at all, to minimize the coils' exposure to moisture. After closer examination, it was obvious that there was little room for improvement... but there was one small thing that could be done. I found an opening above the radiator which led directly to the ignition coils.

That opening could allow a limited amount of fog, rain or road spray to reach the vulnerable coils so I improvised a means to close it off. I formed a shield which I cut from a flexible plastic duotang (a plastic 4L oil jug should work as well) and then fastened it using the upper radiator support bolt.

Having closed the opening completely, I initially thought the now-absent air flow might cause over-heating problems for the coils but I've put a lot of miles on the bike in extremely hot weather since then and haven't experienced any heat-related coil issues (knock on wood).

Since the opening is an odd shape, forming the shield was time consuming. If anyone is interested in this minor modification, you can make the job quick and easy by simply downloading the template image (scale accordingly - final size should be 165 x 73mm):

Coil Moisture Shield Template  •  

It should be known that this is a Hail Mary at best. I came up with this idea out of desperation. My coils had left me stranded countless times and spraying them with various protective sprays had little benefit. Still, something had to be done but I just didn't have the money to spend on new coils at the time. This was all that was left for me to do. In reality, it only prolonged the inevitable. I've since replaced the coils but the shield is still in place because it does provide some small degree of protection - but it isn't much. In practice, this shield only provided just enough protection from moisture to give me an additional 10 minutes to reach my destination before the coils started misfiring as always. It provides very little protection but may mean the difference between being stranded and getting home. I want to be clear that this is not an effective solution - it's just a tiny bandaid!