Chuck, never tasted the sand there thankfully!!! You haven't lived until you've gone WFO under the bridge into a blind down hill right hander at 150 on a motorcycle.... CR
Chuck Voboril <[EMAIL PROTECTED]> wrote: Chris, I hope you managed to stay out of the sand most of the time at the Bridge :-> Delightful place. Musta been fun. The state of the art now ( sorry Art) is that new performance bikes and snowmobiles are ALL pretty quiet and the aftemarket has a really tough time making any more power at all with better mufflers. They can make them lighter and shorter lived, but no more HP I do know that stock 160 HP 2-stroke snowmobles like the latest F1000 AC have lighter mufflers than super bikes. About 1/2 the weight- roughly 15# vs 30#. The noise standards are different, so this may not be completely fair. As I've mentioned before, a CVT machine has more potential for equivalent quieting with low exhaust weight than a motor with the same HP that has to be quiet over a wide RPM range. The quietest high performance combo might be: CVT AND a 2 OR 4-stroke with a turbo and a big muffler. There have been 2-stroke waterbikes around for many years running both superchargers and turbos on the same motor. Chuck >From: Chris Reinhardt >Reply-To: [email protected] >To: [email protected] >Subject: RE: [F500] Quieter Engines (maybe) >Date: Sun, 3 Dec 2006 11:16:38 -0800 (PST) > > OK let me date myself... Back in old days, pre-1997 at Bridgehampton whe >did sound level checks on the race bikes, it was 1/2 redline, 18" from the >muffler tip, @ 45 degree angle. If I can remember back that far the limit >was like 97db. We ran race cans and sometimes a hollowed out WD40 can hose >clamped to the tail pipe... If you spotted a sound cop, you rolled out of >the throttle, and then stabbed it again!!! I had a CR500 in a Hawk >chassis, and I was told it was the loudest thing out there!!! > > CR > >Chuck Voboril wrote: > BTW, I got a complete 1300cc Hayabusa motorcycle exhaust system >including >Tri-Y header, intermediate pipes and mufflers to study. > >It is suposed to meet the 80 dB motorcycle noise limit, but that 80 dB is >hard to compare to ANYTHING else because the standard says it is measured >in NEUTRAL with the motor at barely cracked open throttle holding the motor >to a specified low RPM. > >The mikes are supposed to be aimed 45 degrees to the axis of the bike >(aimed >from front towards the back on the side) and located very very close to the >bike. > > > >Chuck > > > >--------------------------------- >Need a quick answer? Get one in minutes from people who know. Ask your >question on Yahoo! Answers. --------------------------------- Any questions? Get answers on any topic at Yahoo! Answers. Try it now. ________________________________ FormulaCar Magazine - A Proud Supporter of Formula 500 The Official Publication of Junior Formula Car Racing Subscribe Today! www.formulacarmag.com or 519-624-2003 _________________________________ _______________________________________________ F500 mailing list - [email protected] To unsubscribe or change options please visit: http://f500.org/mailman/listinfo/f500 *** Please, DO NOT send unsubscribe requests to the mailing list! ***
