Kid Kart Comer 50CC

[Genes1s`]

Hey guys,

I sold my son's Minimoto Electric Go Kart in favor of 50CC Comer Kid Kart.

Minimoto

50cc Comer

My son really misses the quiteness of the E-Kart!

Is there away to quite this down? we got this kart after spending 12 laps on the track on the same kart (rental). He loves the speed and feels, but can't stand the noise.

He's not doing any race or anything like that anytime soon. I just want him to be comfortable with the kart and the track this summer/fall and see how it goes next year.

 

[Denny]

You may want to tell Jr. to buck up. Sad to say but with speed and power also comes a little noise. There is good news however ear plugs are cheap and will save his hearing for when he is old like me. Have fun with the kart!

Denny

 

[DirtyDamage]

Thing sounds like a Chainsaw....
I'm with denny, throw in some ear plugs, at the track no one will care, even a good helmet should help ease the noise....but then again maybe it's you whose annoyed, LOL!


There is two Comer 80's on my CL for $600(ones blueprinted)

Hmmmm....maybe throw it one on for my sister....

 

[kheper]

The engine actually sounds quiet for a chainsaw. You could fab an expansion chamber. The simplest design is a header, tubing, two funnels welded together for the chamber and smaller in diameter tubing for the out-pipe. Clamp a silencer on the end of the out-pipe. It would reduce the noise and not impair performance. I had a Bill Wirges expansion chamber for my Kawasaki 90. The pipe was less noisy but the performance was substantially better than the stock pipe. Wirges used a cone baffle for the silencer, consisting of fiberglass wrapped around a wire-mesh cone - but built inside of the pipe.

 

[Russ2251]

The simplest design is a header, tubing, two funnels welded together for the chamber and smaller in diameter tubing for the out-pipe.

Too bad it's really not that simple.
Building an expansion requires a great deal of expertise. Must know exhaust and intake port size and timing, displacement, compression ratio, bore and stroke...etc.
One does not just simply weld 2 funnels together.
Do an on-line search for expansion pipe calculators. There are literally dozens of them out there. Some work better than others.
This guy is pretty good at what he does.
Wikipedia has a good article on expansion chambers.

 

[BirdFanatic]

ear plugs solves everything not really just this problem .

 

[kheper]

The simplest design is a header, tubing, two funnels welded together for the chamber and smaller in diameter tubing for the out-pipe.

Too bad it's really not that simple.
Building an expansion requires a great deal of expertise. Must know exhaust and intake port size and timing, displacement, compression ratio, bore and stroke...etc.
One does not just simply weld 2 funnels together.

As stated: "The simplest design" for an expansion chamber does involve welding two, extended funnels together. The performance of such a pipe is superior to what appears to be a chainsaw/lawnmower/tiller/etc. muffler on his engine.

 

[OzFab]

I'm with kheper on this one (not excluding Russ' input), a proper exhaust with a silencer will make it quieter but, it will still make a bit of noise, enough to keep him happy...

 

[Russ2251]

The performance of such a pipe is superior

True enough...but MUST be properly designed or will be a backward step and will rob power instead of enhancing it.
I prefer the old school fiber-glassed megaphone exhaust.

 

[Genes1s`]

Thing sounds like a Chainsaw....
I'm with denny, throw in some ear plugs, at the track no one will care, even a good helmet should help ease the noise....but then again maybe it's you whose annoyed, LOL!


There is two Comer 80's on my CL for $600(ones blueprinted)
Hmmmm....maybe throw it one on for my sister....

It would be nice to make it quieter so we can take it to empty lots and set up cones since the go kart track is 45 minutes away.

I'm thinking of this muffler out of scooter.
http://www.ebay.com/itm/400514660214?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[kheper]

That pipe is rather long and sinuous. I hope it fits the exhaust port and around the engine, and even if it does, it will need to be braced sturdily to the frame.

 

[Genes1s`]

So, I bought used Scooter muffler and header off Craiglists for cheap to experiment. This muffler is off 50CC 4 stroke scooter.

Cut off the flange off the scooter header and made my own header (excuse my welds). The huge muffler is right behind his back seat, not feeling good about it but there is not much space, unless I go with much smaller muffler...

Should be able to try it out tomorrow to see if it makes it any quieter. If it does, I'll find better solution that is smaller, more compact, and not right behind his back seat.

---------- Post added at 09:37 PM ---------- Previous post was at 09:20 PM ----------

Helmet..

 

[Poboy kartman]

ear plugs solves everything not really just this problem .

What? What? I can't hear you.....hey!!!!

You know what? These earplugs may not solve everything.....but they do come in handy!!!!!

 

[DirtyDamage]

Helmets are always good

 

[Genes1s`]

Whoa....what did you do?

Stick your head in wire EDM machine or something? That is a clean cut....

 

[mckutzy]

Hehehe a wire EDM for sure....
I'm guessing spontaneous Kartial inversion....

Lived to tell the tale... Good to hear...

 

[Genes1s`]

well, I fired it up and it didn't really help that much. The muffler reduced the pop,pop, pop sound of common 2 stroke sine wave but the mechanical valve train noise is still there which is understandable. It was bogging down also and running a little rich.

Well, while I'm waiting on the pedal riser, I'll work on the pedal extension. I was seriously going to order electric motor and controller and make it e-kart but I think after the pedal riser and the extension I'll take it to the track with my son and see how he likes it.

 

[DirtyDamage]

That is just a picture of a helmet I saw on facebook. LOL

 

[OzFab]

Excuse me for being a little harsh but, do you even know what you're saying? Since when does a 2 stroke engine even have a valve train to produce

mechanical valve train noise

As for

bogging down also and running a little rich.

There's two possible explanations:
1. the mixtures need adjuating or
2. THERE'S NO EXPANSION CHAMBER which is where the power is made...

 

[Denny]

2 stroke engines don't play nice with 4 stroke mufflers!

Denny