Trials Australia Forums

Hey guys,

Quick question about the exhaust packing in my 2010 Beta EVO 125 2T. I've noticed that my bike compared to other bikes of similar age is a lot louder. Most other bikes I can not only hear the exhaust but also a bit of engine noise too, there exhaust almost seems to "putt" where mine seems to "pang". Mine is a more of a harsh sound and it sounds like the packing is not absorbing much of the sound at all, I popped the end cap off the bike to discover a bunch of grime and goop inside the lower silence itself and similar but a lot less inside the end cap. The goop in the exhaust is blocking all of the holes in the metal baffle. I've read that if you get the exhaust hot enough some of this can burn off, but this looks really goopy, what's the best option in my case? Go for a hard ride? New silencer time? Throw some petrol down it?

Photos inside the exhaust system (scroll down for all the photos, click to zoom): http://imgur.com/a/eyRKH

Edit: I'm running 98 octane with Motul 800 2T oil, 72:1 (same as the previous owner)

Thanks

Just get some new packing from any bike shop or pink batts from a hardware store, wire brush the core or re drill the holes out with a drill bit of the same size as the holes, then repack ,not too tight or too loose, can use tape to hold the packing in place when pushing the whole lot back in to the muffler body. Do it few times a year for best performance.

Can someone enlarge on this? my 2013 EVO 250 has the slightest near hesitation just off idle & having checked everything else out to the best of my ability, am starting to wonder about carbon & goop in the exhaust. I try & find a bloody big mountain climb as regulary as I can for clean out purposes. When I say hesitation I mean a halfa miss sorta almost.

jml

its a tough one...I am an advocate for using heat to burn these out mainly because the result is the most effective. The trade off is the header pipe/expansion chamber exterior will lose its brilliance if heat (a flame) is applied and there is risk of melting the fine mesh inside. Alternative to that is to take it to an engine repair/cyl head workshop and have them soak it in their acid bath which will strip it clean (or find out what acid they are using and attempt it yourself). you first need to decide if you want to keep the original appearance or not. Then you can investigate the options. The tailpipe/silencer component can be sorted at home easily.


Regards
Denis