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Discussion Starter #1
so what is everyone gonna do?

let's start talking about what would be proper fixes for four stroke/two strokes of all shapes and sizes.

was planning on bringing the rs 125 to chase aaron around but the news letter said none of the rs125's made the 101 cutoff. zach, any insite?

i got some whopping megs on the cb350, that used to have some fiberglass packing in them. where can i get some more of that stuff and how effective will it be in silencing the bike?

i'd hate to put the stock pipes back on. for one, they are way low, and i'll grind the hell out of them in every corner.

come on dudes/chicks, let's chat about this!

tex

p.s.- joe c. you might have to pick up a set of stock pipes for me from chris marshall. he said that he probably has a set or two to use.
 

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You should be able to get muffler packing at any decent bike or "powersports" store. FMF, SuperTrapp and others all market it. Also can be had from Dennis Jerk et al.

FR
 

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So the 125's are not able to run? What's up with that? Stremfper, do you know of this or is bull kucky?

Aaron
 

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I'm working on a solution for four strokes. Involving a SuperTrapp and kind of a cover cone to direct the sound backwards.
JohnnyB
 

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Discussion Starter #5
johnny b,

would it fit on one of your cones that you sell? how far in the r&d are you? any estimate on cost?

tex

p.s.- aaron, i'll quote jim marhan, co-director of granite state championship, "as a side note: ALL the 125cc two stroke bikes exceeded the sound limit, average reading 105db." this was in exhausted notes, vol. 22, issue 1, winter 2005, so yeah, no bull kucky!
 

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Yeah but they've always been loud. Does that mean there not running them or was he just letting us know that they are loud.

Aaron
 

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Tex,
Testing so far has just been dyno...they don't hurt power.
Basically it's a metal collar that looks like this:




That fits over/around the supertrapp disks. The prototype was fit to a meg with 4" disks...too big..looks stupid. I'm going to try one to fit a 3" setup. Haven't done any sound testing...I do have a meter though and will check at some point. Technically it probably won't make the bike quieter...just redirect the sound stright back to help fool the meters.
Hopefully I'll make them to retro fit megs...I'll build the thing as a unit, then slice it down one side....maybe it can be spread out enough to get around the meg mounting plates and stuff...put into place and welded back together.

A set-up I know would probably work is a 3" trapp system INSIDE a 4" trap system.




Something like that.

If I do manage to come up with a deflector of some sort I'll try to set it up so it can be done on the fly at the track with hose clamps, safety wire, drill etc.
JohnnyB





Edited by - jbranson on Apr 26 2005 03:12:50 AM
 

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tex, marhan stated that all the 125s were over the limit. nowhere did it say that they're not going to run them, nor that they had to meet the rules . . . if you read it closely.
 

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quote:
tex, marhan stated that all the 125s were over the limit. nowhere did it say that they're not going to run them, nor that they had to meet the rules . . . if you read it closely.
This 99db thing worries me. The only bike I have that's under 99db is my streetbike with the stock muffler.
 

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Discussion Starter #10
i hope joe c. and others have their own sound meters up at the track. it should be interesting with the cars. i don't believe that half of the cars will make a 99 decibel limit. if the cars are over does anyone think the management will make an issue with the bikes?

also did you all know that the lrrs series still has a 105db limit? did you also know that the new hampshire state legislature just passed a 106db limit for streetbikes.

nhis owners are full of shit if they keep on playing the noise with the neighbors card, and we are full of shit if we let them.

my thoughts.

uncaffenated tex
 

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Discussion Starter #11
johnny b,

those look pretty cool. i will be interested in talking more with you on pipe/meg/silencers/supertrapp options up at the track. i think i'll just buy some packing from the recommended venders (thanks fr) and pack and reweld my existing megs. i however would love to improve the lines of my bike with some new cones and also save the weight potentially with some new headers too. we will talk trackside.

tex

p.s.- don't ya'll forget about the cb350 weigh in challenge. i think we should do it saturday night!
 

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Discussion Starter #13
as michael jackson and the four other guys sang.....

"i'll be there."

super soul singer tex
 

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tex, it has always been 106 in new hampshire. the factories all have to go 99 though. (some stupid thing from california or something probably) yes, lrrs is 105, and the cars get to ignore it too. thats not the issue. the issue is and always has been that the weekends the vintage bikes are there, they are too loud. thats the complaint. well as far as what ive heard. and since we seem to run on holiday mondays, and those nice people want to sit and have a barbque, or hold a wedding, they dont want to hear a g50 or b50, or norton blasting around. (how lame) so they leverage that against the track, who really doesnt give a shit in my opinion. (and i dont want anyone to try and argue that by saying "well, they do let us race there, and give us dates" because thats a bunch of crap.) if they really liked us, theyd stand thier ground and stand up for everyone. and no, none of the 125's passed. so i dont know how theyre going to handle that but i would guess that since they run on our weekend, they will be enforcing the limit. since they did mention it in the newsletter. why else would they. as far as im concerned, if they mentioned them, they are on the hit list. im repacking my old 2-1 system, and am going to try and run it. if its too loud, then i just wont be back until the uscra decides to get real and find some new racetracks or other groups to partner with. theres nothing i can do about that. theres no way im going to build a pipe to run 2 races a year up there. its just out of the question. not to mention on and off the bike every other weekend in may and june. not when we can run with wera and not have to deal with that crap. yeah, it does suck, cuz you guys are like my family when it comes to racing, but its just getting silly now. and i really thnk my pipe will pass, im just not 100% sure. i could be totally wrong. my sound meter will of course be there. but it wont matter, since we all know the cars are being held to a different standard now. it sucks, and they should all get thier heads out of thier asses and wake up and do something. its just gettting rediculous. we're riding race bikes for crying out loud, not 10 speeds.

and im interested in seeing how many people actually are turned away or wont be racing.

jc
 

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Both of my Hondas have the 3" Suptrapp cans with the spark arrestor end caps. They seem to have passed without a problem but I've never run them with megs so don't know if they are down on power. My BMW has no packing in the mufflers at all and is quieter on the DB meter.
bfd
 

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bill, i dont think making power or not is the problem. that will be the hurdle for everyone if its a blanket requirement. everyone will be on the same playing field in that respect so i think its fine. i think the bigger problem is how it affects entries and club support etc.. if the rules the club has to follow are too much of a pain in the ass for other clubs members to comply with, they simply wont come. yeah, if i lived up there still, and raced pretty much only at louden, like alot of people do, id have no problem with the rule. but guys like tex, myself chris m, turnbull and others have other schedules for the year. and tex and i were trying to get people to come up from summit this year for the june race. but im pretty sure weve both stopped talking about it since we know it wont happen. yeah, i was told that this is something that was planned out years ago and people knew it was going to eventually be 99, but i never heard that before. (but then again, i didnt hear about that oil in t2 either) if i had, i would have shot for 99 when my second system was put together. all i can see is its going to hurt the club more than anything else. and it leaves a bad taste in my mouth that im going ot have to rejoin and have to change a bunch of my shit around, and they dont seem to be doing anything worthwhile to get us a new venue thats worth going to. i know bob wants to keep it a regional thing, and it seems like the older the club is getting, the more its becomming like that. and yeah, he does it for the love of the sprt etc....but why not try and make a buck at it and grow? (ive also heard the track in ct fell through, but cant say that for sure since its a rumor) not to mention i feel like at this point i could be bailing out a sinking ship. im so tired of hearing and talking about it all. and it seems like now isnt the time to be trying to get it done on your bike.

see you there.

jc
 

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quote:not try and make a buck at it and grow? (ive also heard the track in ct fell through, but cant say that for sure since its a rumor)
That's not such a bad thing... that track had issues. It'd be like Gunstock, you're not supposed to be racing bikes there. We would've had to ride through a 15' opening in a concrete wall to get from the outer track to the oval. I don't know about you, but when I show up with my bike I want to race, not parade around. My bike is ugly.

Noise: There's been talk for a while now about lowering the limit, so you can't say it was just sprung upon you. Tracks all over are doing sound checks now. Its sometime you need to deal with as more people build homes close to racetracks and then complain about the noise. Yes, it sucks, but its life.

There's a few things I'm thinking about for my bike.
1) Big unoiled K&N air filters to quite intake noise
2) Rubber dampers in the cooling fins.
3) Repack my stingers and pray.

The intake noise from my 34mm open carbs is... loud. I think if I quite that down I should be ok. I talked to Turkington about it, he runs a big unoiled K&N on his Bultaco, says it doesn't affect jetting at all. Plus it'll prevent small children from being sucked in. And its all about the kids safety these days.

Bitches.
 

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I've gone to un-oiled KN filters on all my stuff, definately quiets the sucking noises in the garage...no idea if it makes a difference on the track.
I'm also doing the cylinder fin damper thing....between as many fins as I can.
I just fired up Hiroshi's bike with 3" trapps...sounds pretty quiet to me, probably 20% quieter than 4" trapps. I did some math on them, then Aaron talked to them and we found that supposedly 9 3" disks equal 6 4" disks as far as breathing goes. And to be honest, most vintage bikes I've seen in the state of tune that most of them are, make more power with a muffled exhaust that they do without. These aren't MotoGP bikes with ultra exotic engines tuned for peak hp. These are in the big picture mildly modified street engines that respond better to mid range enhancements that anything else. My laps times dropped about two seconds when I went from 12 4" disks to 6.

As for regulations...it WILL happen at all tracks eventually...so do it now, or do it later...doesn't matter. Why change pipes? If you have it quiet enough for Loudon then run it the same way everywhere....it probably makes more power that way anyway. Some people still have a very hard time realizing that noise does not equal power. So far every bike I've ever built made both more power, better mid-range, and easier to tune as it got quieter. It takes a highly tuned engine with very very specific exhaust system dimensions to take any advantage from an open megaphone exhaust. Most people running open megs would be very surprised if they actually put their bike on a dyno and compared it with a muffled exhaust. And...I'll give away a hp on top any day to pick up 3hp in the mid range.
JohnnyB
 

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I've been using K&N's on everything just out of fear of sucking in debris or water and wrecking a motor. I work too slow to fix a major problem in short order.
Last year Bruce Smith had a stuck motor at one of the events from (I think) rain water going through the open carb mouths. He and I were on the track at the same time in the rain and he put the bike in the barn when he got home until the next event. Both the kickstarter and electric start couldn't turn it over. The starting rollers freed it up and it was fine after that.
That silver bike has had a hard life.
bfd
 

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I've seen the reverse happen too...I've seen KN gets so soaked with water that they choke the engine. We don't run rear fenders so in the rain I run some duct tape across the frame to block the water from hitting carbs. In a driving rain I'd opt for open carbs and a duct tape fender...in a heavy drizzle I'd opt for the KN.

A bit of water usually won't hurt a engine at speed....but you don't want to drown it and then let it sit. At some point I'd like to come up with an airbox setup...I think it would help power and prevent water problems.
JohnnyB
 
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