I have an 01YZ250 and a new FMF gnarly pipe. This pipe has two embedded rubber seals in the flange.
Do I need anything else (I plan on using some high temp silicone as well) to seal this pipe?
I can't remember what I did when I put the first gnarly on there and don't want to have to clean off silicone in case there's additional seal(s) I need.
I got an email back from where I bought the pipe and he said that all I should need is the embedded o-rings in the pipe. According to the microfiche there's no copper piece. I think I will just slap her together and check for an exhaust leak.
The copper piece is so the vibration of the pipe on a 2 stroke does not deform the cylinder outlet.The pipe is not bolted tightly to the cylinder ,thus the springs that attach it,and it will beat the daylights out of the cylinder exhaust port...which will be exspensive to replace,as opposed to the cheap copper ring.
But there's nothing on the microfiche about this copper ring. When I took off the old FMF pipe, there was no copper ring, and the exhaust port is flawless. I don't think the YZ's use them?
Well I'll add that to my small book of knowledge...I've never owned a YZ...my KX,RM,and CR's have all had them.But if it isn't there on yamamha..apparently they dont feel the need.That's good to know for future reference...should one of my buddy's buy a YZ .Just rip it up and feel the new power in that case!!
Well, I had the gnarly on before, it was too beat up so I replaced it. I had a new top end put in, and new gnarly. This time I am using a different FMF silencer, it's longer. I was using the shorty silencer before.
I fired her up for the first time yesterday and rode around my yard. Oh man, I don't know if it's the pipe or the new top end, but she's got so much more power now! :)
Gotcha. Get an Eline CF guard and you won't need to worry. I swear by those things. I'm running the stock pipe with one and if I took off the guard, the pipe would look brand new. Kind of pricey but if you're having to replace pipes here and there, it's worth it. You also get piece of mind if you're offroad racing.