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Discussion Starter · #1 ·
So looking at some full pipe designs for the bike came across this on aliexpress.

What is the purpose of the loop vs a regular straight pipe? Is it for noise, back pressure?

Im interested in this one because it has a point to mount it in the center vs where the straight ones dont and just hang by the exhaust hanger and headers.
 

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i had a friend who modified honda hatchbacks and he had one EG hatch featured in Import Tuner magazine cover page, fully built ITB pushing 240whp N/A, he had a loopyloop exhaust pipe on it.. never asked why but that hatch was unbeatable...
 

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Discussion Starter · #5 ·
Other bikes have it too, honda grom for scientific purposes here

but I would really like to see something like this on a dyno compared to a regular straight full exhaust
 

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I used to have a Z125 and they also have some loop exhausts for those as well. I asked a seller what the purpose was and he said it was to help retain some back pressure and low end power. No dyno for proof.
 

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TST had a new vid on YouTube today for a Yoshimura full system for the Honda Grom and it had the loop in the pipe. So it's not just a dodgy Chinese thing. If I was to guesstimate I'd say it's to lessen the noise.

Sent from my SM-G930F using Tapatalk
 

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Discussion Starter · #8 ·
Crazy eh? I couldnt find anything on the net about this haha

Like why would someone go through the trouble of extra piping and the hard work of welding a loop? This will even add weight.
 

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Repsol Honda and other motogp bikes have a loop designed into their exhaust system as well
 

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It's to help with silencing utilizing the curves of the pipe without having as much air flow restriction that you find in the chambers of a muffler. Mugen and a few others make twin loop exhaust systems. You can find information about them on the Internet.
 

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Has anyone tried one or races with one?
And can measure the header tube diameters?

Liking the length it gives,
The centre hanger mount,
And the ability to run a short muffler.
Its china, its cheap,
And need one by about yesterday
Cant afford the $1300 SC-project I really want yet.
 

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Interestingly, dynos on the R3 have established that the Yoshimura R-77 full exhaust delivers more HP with the noise-reduction insert in place than it does without it. The loop in this exhaust may perhaps similarly improve the exhaust flow.
 

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Anyone got some sound clips of this? At that price, I might actually get it. Although, since it's a full exhaust, I'm assuming I'd need a PCV as well?
 

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The loop is probably intended to add length while still enabling the overall exhaust length to terminate not far behind the swingarm pivot.

However, note that it cuts ground clearance under the bike by at least 1.5 inches (apparent diameter of the tubing) with the loop. This won't affect normal leaned cornering but MIGHT not clear some parking lot speed bumps.

Jim G
 

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on a performance context, yes, pipe length is tuned for scavenging. in general, a longer exhaust pipe is tuned for better low-end response while a short (underbelly) pipe is more for the top-end power.
 

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I cant load pics from the other thread,
But id say my race fairings will fit.
They need lots of modifying anyway.

This allows for a short muffler to suit my rearsets and a custom hanger.

I may regret this :p
But its cheap and not for the road.
 

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Anyone got some sound clips of this? At that price, I might actually get it. Although, since it's a full exhaust, I'm assuming I'd need a PCV as well?
Nobody buys loud exhausts for 180 degree parallel twins for sound surely!?
They sound horrible.
Its for weight saving.
Yes you need an insert and a tune.
Which is where the big expense is.
 

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Just took a closer look at the ad:

1. Notice that the photos at the top of the ad show one (steel) muffler, and the photos down below show a DIFFERENT (CF) muffler. Are you SURE you get a muffler with this deal?

2. Notice the weight? It's 3.5 kg = 7.7 lb. That's light IF it includes the muffler, but HEAVY if it does not.

You might want to ask the vendor if the muffler is included, and if so, WHICH muffler.

Jim G
 

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Just took a closer look at the ad:

1. Notice that the photos at the top of the ad show one (steel) muffler, and the photos down below show a DIFFERENT (CF) muffler. Are you SURE you get a muffler with this deal?

2. Notice the weight? It's 3.5 kg = 7.7 lb. That's light IF it includes the muffler, but HEAVY if it does not.

You might want to ask the vendor if the muffler is included, and if so, WHICH muffler.

Jim G
I dont shop on aliexpess, its dodgy as.
Cant trust any china vendor for details.
The u turn headers arr all over ebay in any muffler you want,
Along with the spring mount straight type akra race clone,
And the cheaper type akra low mount clone which was release early.
 
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