Good day everyone...I'm new to the forum and bought a 2019 Z800 this summer and am just loving this thing...anyhow it's been a wet fall in Northern Ontario and when I go out on the muddy trails my exhaust outlet keeps plugging up with the local mud which has a very high clay content and goes rock hard when exposed to the heat from the exhaust...last time it plugged over halfway closed and you can really feel it in the performance of the machine...has anyone else had this issue?  I am going to get a Two Brothers and programmer over the winter but looking for a fix to get me through the rest of the season...any help is greatly appreciated...Thanks and love this site!!!

[2015 Z Force 800 53/Trail EPS]

Welcome. Wow...that's a new one. Have not heard of that happening before but..not surprised because of the angle and location. In the How Tos I modified mine to accept a silencer but it changed the length and angle to a point that your issue may not happen. It's a thought anyway.   

Welcome. Wow...that's a new one. Have not heard of that happening before but..not surprised because of the angle and location. In the How Tos I modified mine to accept a silencer but it changed the length and angle to a point that your issue may not happen. It's a thought anyway.

Thanks for your help...I just read the post you mentioned and I am going to whip something up similar...just wondering how lean did your machine run without the spark arrest, is it something very concerning?  From what I understand the EFI systems have some tolerance but it is not very broad...will these parameters change with altitude as well?  Thanks.

[2015 Z Force 800 53/Trail EPS]

Welcome. Wow...that's a new one. Have not heard of that happening before but..not surprised because of the angle and location. In the How Tos I modified mine to accept a silencer but it changed the length and angle to a point that your issue may not happen. It's a thought anyway.

Thanks for your help...I just read the post you mentioned and I am going to whip something up similar...jsut wondering how lean di your machine run without the spark arrest, is it something very concerning?  From what I understand the EFI systems have some tolerance but it is not very broad...will these parameters change with altitude as well?  Thanks.

It was too lean without the spark arrester and with the arrester it was on the edge. My latest variant...which I didn't publish was to re-use the OEM end and arrester. I just cut off the pipe end and installed the new end over it using the gaskets to sandwich it together. So now, although a lost a little top-end power, I gained my low end back and its even quieter. If you look close in these pics, you can see the flange from the OE end sandwiched in under the new end:

Perfect...I now know what I need to do, thank you very much and hopefully the new one won't plug up with gunk.