Custom Pipe

[Bighomedog11]

Hey, I just made this custom pipe today for my kart. It is straight pipe, and something i just welded up for it. It is really good and flows nicely. I think it is better then my other straight pipe i had witch was short.
This is what i had before

Now i made this one

 

[Kenny_McCormic]

Needs bracing.

 

[Bighomedog11]

yeah, i am not 100% finish with it. I am most likely going to weld a bar onto the frame and brace it like that, But i just hate to weld something on the frame that i might change later. But a little tak weld should be find and easy to break off

 

[Blazkowiez]

Weld a bracket that you can bolt bracing to that looks clean. Tacks don't hold for basically anything, they are not meant by nature to hold and is not technically a type of welding.

Lets say I want to weld a bolt onto a kart, I would TACK it into place with one single burp, and knock the bolt left, right, up, or down in order to gain proper alignment, then I would run a bead around the bolt to secure it. Should you just put a just a single weld on there or a "tack" then the first bump you'll hit will break and ruin any work you've put forth and cause more time and effort than if you had done this properly to start with.

If that sounded like a rant against your term, it is directed towards those people who thinks going into a welding shop like those businesses surrounding ours asking for "a quick tack" expect it to cost next to nothing versus a "a solid weld".

 

[Bighomedog11]

thanks for that great reply! I did not take anything against me but i am thinking about doing the bracket method for it. Just weld the brackets onto a pipe and just bracket it down onto the frame..

But what do you think about the pipe though?

 

[Blazkowiez]

I really dislike anytime people use plumbing fittings to design an exhaust, if you should be making something from scratch do your best to make sure the inside of the pipe is amazingly smooth for better flow. If you used the fitting from the stock exhaust to mount your pipe did you take time to bore the exhaust pipe to remove the edge?

This is better than some attempts I've seen from customers but still needs some fine tuning.

If you have more time than money consider this option. Search online sites for production mufflers for these engines in racing applications?

If you feel anyone has helped you with the kart or has posted something that adds information to your personal kart knowledge feel encouraged to use the thank function of the forums, for many of us this is one of our reasons for posting.

 

[Bighomedog11]

Oh, Well it performs good. But i did not use my stock muffler mount. I had another muffler on there and i just used that mount. And yest i bored the edges. I basically had to make the whole mount a weld because the old mount was just some thing aluminum.

 

[Blazkowiez]

In that case as a home project I see no problem with this aside from perhaps some sort of wrap for safety so people do not burn themselves.

 

[Bighomedog11]

Thanks, I was trying to make something like that in that pick but something more to fit my kart. I was kind of thinking of a old school beetle/dun buggy look.

 

[redsox985]

If you feel anyone has helped you with the kart or has posted something that adds information to your personal kart knowledge feel encouraged to use the thank function of the forums, for many of us this is one of our reasons for posting.

I think you want 100 "Thanks."

 

[slideways]

Not bad dude.. tubing is still too big but at least it has some bends in it. Better than what you had. Did you feel more torque and midrange with that pipe?

I'd brace that upwards from the bottom it if was me. Your cage will tend to rattle around more than you think and may break that pipe.

Next step is to get yourself a filter adapter and drill your jet to .036. That will complete your basic bolt ons. Wrapping that header is a good idea as they mentioned. Tiny performance increase, safer to the touch and it will actually quite the noise a little from inside the pipe but still sound nice exiting.

 

[Bighomedog11]

Thanks! Yeah i notice more torque in my lowe-nd and mid-range. It seems like it gets up to speed faster and flows better. Less popping.

I am going to brace it somewhere onto the back of the frame. But i think the pipe fits perfect it is not too big for the kart or nothing. It just looks bigger in the pixs but it is good

 

[Blazkowiez]

I think you want 100 "Thanks."

I'm aiming for 1,000 but they have to count.

 

[KieranM]

when i hit 50 i will be happy

 

[Deep Sea Diver]

Not bad dude.. tubing is still too big but at least it has some bends in it. Better than what you had. Did you feel more torque and midrange with that pipe?

I'd brace that upwards from the bottom it if was me. Your cage will tend to rattle around more than you think and may break that pipe.

Next step is to get yourself a filter adapter and drill your jet to .036. That will complete your basic bolt ons. Wrapping that header is a good idea as they mentioned. Tiny performance increase, safer to the touch and it will actually quite the noise a little from inside the pipe but still sound nice exiting.

You said 'at least it has bends in it'. I'm thinking of doing the exact same thing with my 6.5 clone. My last kart was 3/4 exhaust and I just had a 10" threaded piece of straight pipe to put into it. I really didn't see any changes in performance, except it sounded different. Is there a difference if it has bends vs. straight? Another guy on this forum said make sure you put your muffler on the end of your straight pipe. I can fab it up to have it's stock muffler on the end of the straight pipe, but does it make any difference? Thank you for replying.

 

[Bighomedog11]

Well i notice with this muffler it i can tell a difference in my lowend and mid range. It seems like it gets up to speed fast and has a constant flowing sound. Instead of a popping one.

 

[slideways]

I can't even begin to explain the science of exhaust flow to you guys on here. Probably best to search for it on wikipedia and other engine related sites. Search backpressure theory, reversion, exhaust theory etc..

You can run a straight pipe with success but you have to consider the type of application. A racing kart running an open track at 8500rpm+ can get away with a 12" long straight pipe tuned specifically for its rpm range for peak power using a dyno. For an offroad kart bouncing around and stopping/starting you want torque. Generally what builds torque is allowing the exhaust gases to stay in the pipe longer and have to go through a few bends possibly. We see alot of the clone pipes being curved mostly for clearance but this also gives them the most power as manufacturers have certainly tested them on a dyno before they sold them.

The muffler on the end helps with sound mostly but when placed well after the tubing seldom has an effect on performance. I have found that you gain more power if you simply plug a decent muffler on the end of a nicely flowing exhaust system vs using a factory muffler like what is on the clone or most other small engines. For example... a stock clone muffler will be outperformed by the RLV pipe and muffler combo or the exhaust i fabbed up for my minibike which is made out of an old nerf bar and has the tubular briggs muffler on the end of it.