GasGas muffler packing/Trials tires

Discussion in 'Trials' started by Undertheoaks, Apr 9, 2013.

  1. Undertheoaks

    Undertheoaks Adventurer

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    New to the trials scene and have a 05 txt280 pro curious about muffler packing do you use normal packing for two strokes or speacial GasGas packing ? Thanks. And where is the best place to buy Trials tires ?:ear
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  2. mung

    mung Been here awhile

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    Normal two stroke packing material will work but your dealer will sell you official GG muffler packing material if you want. While you are there get some tires so when you need some parts or advice he will still be in business.
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  3. Sting32

    Sting32 Trials Evangelist

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    This just happened to been covered on another forum, (JSE John Stoodley, gasgas expert tech) chimed in as well, problem is, was it at gasgas forum on trialscentral.com, or was it on Thumpertalk.com? hmmmm....

    Get the loose stuff, dont wrap or pack too tight. most nobody does the "mid" muffler, just in case you were thinking about that too.

    05 means you have 4 rivets, small short ones to drill out and replace... it is easy, I usually have to do it every other year, if I keep the bike that long.

    as Brewtus would say, [​IMG] "welcome to the dark side..."
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  4. the toe cutter

    the toe cutter Adventurer

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  5. Undertheoaks

    Undertheoaks Adventurer

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  6. Seavoyage

    Seavoyage Been here awhile

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    I'll see you guys this weekend at the British-American Cup.

    Sting32 mentioned Chinese X-lite clone (Vee Rubber VRM308? tires) imported by GasGas in another forum. Anyone want to chime in on quality compared to a D803? Price from Dale? http://www.trialscentral.com/forums/topic/18167-vee-rubber-tyres/

    Interesting that the GasGas Eco comes from the factory with Pirelli MT43 tubed tires mounted- now that's a stiff sidewall, so maybe the Vee Rubber may be ok.

    Re: Exhaust packing: Silentsport packed loose http://www.ktm-parts.com/mm5/mercha...gclid=COjvi6OBxLYCFcODQgodczMAZA#.UWdnlpPvuLE
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  7. Twin-shocker

    Twin-shocker Long timer

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    On a bike that old you will need to repack front and rear mufflers, and I would suggest using caution in regard to selection of tyres, unless you are a play bike rider who doesnt want to compete seriously.
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  8. DerViking

    DerViking Shred

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    I run old bald tires most of the time. When I do occasionally throw on a new tire it is for a comp I know will benefit from it, like Ute Cup. Otherwise, riding with limited traction is good practice. We have a lot of sandstone and granite around here, very hard on tires. If you cared about fresh square knobs, you'd go broke. I compensate for worn tires by running very low pressure, just enough that I don't rim knock too bad on splatters and square edges. I use up about 1 tire per year, though I have 4 in the rack of differing levels of wear, and one with pretty good edges I am saving for the National at Hualapai.

    The Dunlops are fine. I could tell no difference last time I had a Michelin. Graydog ran a off brand, can't remember which, and it was kinda stiff to my feel, but he was running tubes on his Eco.
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  9. Sting32

    Sting32 Trials Evangelist

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    Gasgas isnt really involved with the tires, Dale likes the tires and they are cheap! I didnt like the grip from the ones I had 3 years ago. I was told last year they changed the "formula" or something. I might have a try with one later this year, since I don't have the money for my true X-lites... IMHO they (even the one I tried 3 or 4 years back) make an outstanding value for amature or any "new to our sport" rider that has bought used bike with crapped out worn tires. IMHO if you see what I was saying.

    I have held to same theory for many years, as Derverking, I almost made me a practice rim, but I dont have the 4-500 to do that, with other things I like to do... and I HATE changing tires! I just Hate it, I have to do it, for more than just my bike, but I friggin HATE IT...
    But I also find out sometimes practicing without grip, then having grip can throw your timing and balance off.

    Well, my swear jar is filling, I might have $ for rear X-lite soon.

    (did I mention how much I dislike changing tires?)
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  10. Sting32

    Sting32 Trials Evangelist

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    **** you (most) don't bother to ever repack the front muffler, it is a tedious job requiring cutting the muffler apart, then except the 02, the muffler is aluminum, and a special welder and skill to operate that welder...
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  11. Undertheoaks

    Undertheoaks Adventurer

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    Thanks for all the info, I'll repack the rear for now and probably check out the Dunlops.:D
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  12. Twin-shocker

    Twin-shocker Long timer

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    It will run a little better if you repack silencer, but will never be as smooth and powerful as it would if you repacked front as well. In most cases alloy front boxes can be repacked without welding. Simply cut a window in the rear part of the exhaust that doesnt show, hook out all the old packing, repack and then cut out a piece of aluminum slightly bigger than the window you have, drill holes to pack pop rivets or riv-nuts, apply high temp silicone sealer round the edges, and then fix your cover piece using whatever method chosen. Dunlops work well for rocky terrain, but not so good for mud, cambers, tree root type sections as very rigid side walls.
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  13. GapRunr

    GapRunr Been here awhile

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    Resurrecting an old thread here... I've got a 2003 Gas Gas TXT 280 Edition. The front muffler is currently empty. It had gotten pretty oily so I hung it up and applied heat and the sludge eventually dripped out along with what little was left of the stainless steel wool packing material. I'd like to repack it. Does anyone have a source for the proper steel wool? Will any coarse steel wool do the job?

    I've repacked the rear muffler before, and need to repack it again after completely submersing the bike at the CVOTC event last month so thought I would finally get around to repacking the front muffler while I was at it. The bike has gotten louder and seems to be missing some of its low end punch compared to an identical bike I rode with significantly less hours.
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  14. the toe cutter

    the toe cutter Adventurer

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    I'm curious to know what specific type of steel wool (or other packing) people are using as well.

    Here is an interesting article with good photos and comments on what packing he used for the mid pipe. Hope this helps.
    http://www.motomerlin.co.uk/blog/?p=735
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  15. motobene

    motobene Motoing for 46 years

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    Lots of 2-stroke packing material available. The project 2005 GasGas 225 I have has final muffler length that will require ~13" of material to wrap around the perforated center pipe, or two wraps of narrower material. I see there are more standard (like fiberglass wall insulation) and string-type materials of many rands. Not sure if one is really superior to another.

    The smallish, older-style center muffler of the 2005 was cracked when I got the bike. Some of the packing was gone, but most was still in there. I should have tried to pack more in before TIG welding it, but alas, water under the bridge. I'm not going to cut into it further.

    Just packing the final muffler should do some good to lessen the `70s 2-stroke poppy noises.

    The later one-piece mufflers sound deeper and better.
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  16. ADVCoop

    ADVCoop Been here awhile

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    When I had my 1992 GG GT25 I cut the back of the silencer open and stuffed it with loose 2 stroke silencer packing, then made a new sheet metal cover and siliconed/pop riveted it on. The stuff I used looks kind of like yarn. I also cleaned the perforations in the pipe. It made absolutely zero effect on the noise level. I think now it was the mid pipe. I ended up putting a silicon 90 degree elbow on the exhaust outlet to aim the noise down and that actually helped the perceived noise a lot.
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  17. motobene

    motobene Motoing for 46 years

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    Thanks for that feedback! I was wondering if repacking the final muffler might have little effect. Now I suspect that will be so. I was also thinking yesterday of doing what you did, modifying the muffler exit with a spark arrestor or some other baffle. A silicone elbow (silicone is high temp) is not something I would have thought of.

    Back in the ring-ding days I used to take a bicycle tube, close one end, put in slits, and hose clamp the tube to the muffler exit. Got rid of the harsh popping.

    My 2005 GasGas final muffler tip is diameter 1.272" (32.3mm). Here is a 1-1/4 silicone hose:

    https://www.amazon.com/Universal-Pe...r=8-3&keywords=90+degree+silicone+elbow+1-1/4

    I bought this cheaper one:

    https://www.amazon.com/Degree-Elbow...r=8-6&keywords=90+degree+silicone+elbow+1-1/4

    If the bike is still too poppy I can make a baffle plug to push into the turn-down end. An alternative is to machine a slip-over baffle end, but then why not just buy a spark arrestor?
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  18. GapRunr

    GapRunr Been here awhile

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    I recently repacked my txt 280 Edition, using the loose fill method with premium packing material. I stuffed it down full and tight with a wooden dowel, and filled the end cap before riveting it back on. It made absolutely no difference in noise levels to the 3 year old, frequently wet, once submersed packing material previously in there.

    I am hoping that repacking the currently empty mid chamber with new steel wool packing might help lower the noise levels.

    I wish the people that made the "dB Snorkle" were still around.

    http://dirtbike.off-road.com/dirtbike/review/the-db-snorkel-23309.html
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  19. motobene

    motobene Motoing for 46 years

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    I wonder if packing material can be rammed too tightly? I would think thee needs to be enough transmissibility to inner spaces to absorb the sound energy pulses.

    The Snorkle is prettier than inner tube!
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  20. GapRunr

    GapRunr Been here awhile

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    I did a lot of research on packing of mufflers, and you are correct. Packing it too tightly does not kill as much sound as packing it just a little loose, but it does provide a better heat barrier. I wanted to quell the heat as much as possible since the pipe gets hot. Hot enough that the plastic Carbon fibre look cover has melted a little.
    #20
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