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Silencer Repack (How Do You Guys Do It?)

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I recently had to repack an FMF Power Core II Silencer (2 Stroke). I was curious as to how you guys do it. In particular how do you guys clean the internal perforated pipe. I have done many repacks on street bikes before but this is my first 2 stroke. I found that majority of the packing was oil soaked and majority of the holes in the perforated section were just plain gummed up with oil. I tried different solvents, wire brushing it, scotch pads and last resort started to use a pick and clear the holes individually. After approximately half a dozen holes I said there has got to be a better way (and there was). I decided to torch it. I used a small garage butane torch that has a decent size flame, once it got hot enough it just caught fire but since oil does not have the flash point that fuel has it did not just ignite like you would think. I was able to hold on to the pipe from the inlet side (no gloves) it did not get hot enough, I just stood outside holding it and rotating it around until the flames burnt out. I then tapped it on end of my boot a few times and viola, all the holes in the perforation were clear.

There may be a better way but this was my first time performing this task on a 2 stroke silencer and had never encountered this problem on a street bike.

This is also my first real contribution to this site, I would just like some feed back and your thoughts on this method.

Thanks.

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thats not a bad way of doing it but, ive never had to use more then a wire brush or steel wool and usually it comes clean pretty effortlessly, another suggeustion would be to use a bench grinder with a wire wheel maybe

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thats not a bad way of doing it but, ive never had to use more then a wire brush or steel wool and usually it comes clean pretty effortlessly, another suggeustion would be to use a bench grinder with a wire wheel maybe

I actually tried the wire wheel, it cleaned the outer surface great but did nothing for the plugged up holes.

This bike was a 99' CR250R that was running rich and was not abused as far as I can tell. I mean the exhaust was so gummed up it was like plastic trying to get it out, until I torched it that is, then it just fell out in ash.

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For that condition thats probably all you could do. Ive only had to use a wire brush as well. If you dont fix the rich condition id just repack more often now that you have a clean starting point.

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I own a 1998 cr250 we are about to do my top end, reeds, and silencer re pack. I have a pro circuit expansion chamber, but stock silencer, so I don't know what to expect! I previously owned the bike 4 years prior and I know it has not been done in at least the last 5 years...I'm glad I stumbled across this thread because I'm sure it won't go as effortless as others, so at least I know I can use the torch!

I've been watching videos on youtube. It really looks pretty simple as far as installing it, but if anyone else has any tips or tricks, please share!!

Btw those cartridge re-packs are badass! Pisses me off that I ordered my Fly racing packing yesterday and stumbled across this today but O well, there will be a next time now that I own this bike again.

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I did my Turbine Core2 this summer and found getting it apart and cleaned to be the easy part. Getting it back together required all of my patience and a pair of scissors. Of course I was using the one size fits nothing sheet of packing that I picked up at the local shop. Those cartridges look like they might be pretty convenient.

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You independently discovered the standard way to do it. Heat from a torch will make the carbon flake right off with very little effort. You might also want to check the other end of the pipe--the head pipe--for carbon buildup. You can clean that the same way. For packing on a 2 stroke dirt bike you can just use home insulation--it will work as well as anything you buy, for a fraction of the cost. Wrap it around the baffle tube semi tight, and then use a couple of masking tape loops to hold it in place while you put it together. If you had a lot of oil in you packing, you may need to take a look at your jetting. Are you getting a lot of spooge out of the pipe?

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You found the best way to do it when it is all plugged up, no doubt. I did the whole drill bit thing for a while until I just torched it when mine was all gummed up. I generally repack after 4-6 months now, and the perforations are fine.

I use the FMF packing. From one pouch, I get 3-4 repacks. I've read many of you doing it different ways, but I loosely wrap one layer around and tape it in place. I always pass sound with plenty of room to spare, blowing around 88-90 dba.

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I don't know about the home insulation packing...I've heard bad reviews about the FMF stuff and very good about the FLY stuff, so I bought a thing of it...$7...I mean, that's pretty cheap!!

Guys what are the characteristics of a pipe that needs the packing? Does it just get louder? I've noticed a lot of bike have that tingy crackle pop to them when being wound up from low rpm...Wondering why my CR doesn't have this, and I know I've heard same year bikes have it? Could it be packing or something else? Were about to do my top end, pipe o rings, silencer packing, reeds, etc...Just wondering what makes it pop!

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I don't know about the home insulation packing...I've heard bad reviews about the FMF stuff and very good about the FLY stuff, so I bought a thing of it...$7...I mean, that's pretty cheap!!

Guys what are the characteristics of a pipe that needs the packing? Does it just get louder? I've noticed a lot of bike have that tingy crackle pop to them when being wound up from low rpm...Wondering why my CR doesn't have this, and I know I've heard same year bikes have it? Could it be packing or something else? Were about to do my top end, pipe o rings, silencer packing, reeds, etc...Just wondering what makes it pop!

i tried the fly stuff before...i much prefer fmf's specific packing..

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As you lose packing it will become louder, and of course it will become louder as the holes in the baffle clog with carbon. In extreme cases you may even notice a decrement in performance, but I think almost anyone would notice the loud and harsh sound before it gets that far. A silencer with a fresh repack always sounds "soft" to me. It is very common among 2 stroke guys to use household insulation, but of course you need to remove the paper backing if it has any. It's the kind of job that is really fast and easy once you do it a time or two, and I would think that you could get 9 months to a year out of packing even if you ride a lot. Common household insulation will not work in 4 strokes as the temperatures get to high.

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