Home Forums Shifter Karts Stock Moto too loud for track!?

This topic contains 9 replies, has 7 voices, and was last updated by  Chris Reinhardt 1 year, 1 month ago.

Viewing 10 posts - 1 through 10 (of 10 total)
  • Author
  • #28440

    John Sullivan

    I was running a practice at F1 Outdoors with my cr125 Stock Moto shifter kart with an RLV 4 pipe, RLV 12″ silencer, and RLV 4 hole shifter airbox.  Dave Davies black flagged the kart and told us it was too loud and we need to plug up the airbox.  He said that the rulebook is out the window and that the kart would  not have passed a sound test.  The whole situation didn’t see to make much sense.  I built and prepped the kart to be able to race at WKA and SKUSA sanctioned tracks and events, and I am being told by a high up in the industry that the parts I purchased to be a safe, legitimate competitor are not up to snuff.  My port timing and intake setup are designed for the stock compression and ignition timing of the engine, so when I changed the intake area and number of velocity stacks, I couldn’t get the kart to run with just a carb tune, meanwhile time was passing and my $150+ for the day went down the drain and Mr. Davies didn’t seem to have other suggestions to get the kart back to normal.  Any suggestions would be of great help to my new karting adventure.


    John Sullivan


    David Cole

    I believe that F1 facility has a much lower sound level allowed then most tracks. I’m sure others on here can back that up and can offer you a solution to run under the sound level.


    Christiaan Bouhuys


    I had no issues (was way under the sound limit) last year with stock moto. Only difference to your set-up is that I used a 14″ silencer and the blue two hole freeline airbox.

    Two thoughts:

    1. Your silencer packing may be gone, try to repack the silencer. If that does not help try a 14″ silencer (maybe with downturn end pipe), RLV sells a special quiet silencer if I remember correctly

    2. Try the freeline airbox. It should be better than the 4-hole RLV anyway (the freeline is the airbox of choice for stock moto).


    Good luck.


    Brad Johnson

    I believe SKUSA mandates a 2 hole box, so you might have had in issue if you showed up to a SKUSA race that required the box. I would agree with checking the packing in your silencer as well, unless it’s fairly new.


    John Sullivan

    Cool guys thanks for the advice, I guess I’ll have to make some slight changes.  Sounds like I’ll plug the two holes and get a longer, nicer silencer and run the ole girl.  I thought SKUSA was open air filter for stock moto; they are making 42 hp out of the “stock” engines and are probably running at 90 decibels.  I guess this track like you said has very strict ordinances to follow.  It’s still a bit of a bummer, I guess the greater Boston area is in need of some more sprint-karting venues.


    Brad Johnson

    You’re correct John. SKUSAs rule is for a filter but if a track is in a noise concious area they have the discretion to mandate a box. Goof luck.


    Chris Reinhardt

    It’s been a while since I had to run an airbox….  From my recollection, there were no 4 hole boxes that were CIK homologated, either 3 holes of 23mm, or 2 holes of 29mm.

    In the first post it sounded like Mr Davies gave you an option of plugging one of the holes?  Maybe you should have duct taped one of the holes shut to see if that made the difference?




    Frank Rapisarda

    Hi John, I also ran last year at F1 with a mod moto and Dave told me no way I would pass the sound test . I had a 2 hole RLV box with a filter and a 14″ M4 silencer and it passed no problem. Note it was a new silencer, so the packing was fresh.


    Harrison Potsworth

    This is more of a Boston F1 problem than anywhere else. I don’t know of one other track that is more strict on engine noise then this place. Only engine that doesn’t have a sound issue on that track is rotax.

    If only we could pick that track up and relocated it somewhere else…


    Chris Reinhardt

    Oakland Valley, believe it or not was really bad at one point with the previous people that operated it, and that’s way up state!!!!

    I ran bikes at Bridge Hampton, that’s the worse I ever saw…  They had sound checks at tech, 50% red line with a sound meter, sound police around the track and you would get black flagged if you were too loud, fined even!!!!  We used all kinds of spray cans and elbows on the stingers to get them quiet…  On the grid, you heard “sound cops turn 10″ so you knew where to roll off the throttle….

    It’s one of those things, if you don’t play by the noise rules, you might loose the track…

    Good Luck….

Viewing 10 posts - 1 through 10 (of 10 total)

You must be logged in to reply to this topic.