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Two Brothers S1R Exhaust System Honda GROM 2014-2015

Item: P259958

The S1R Exhaust System combines race derived stainless steel tapered headers with the next generation S1R muffler. Read More

$450.48
$529.98
Save $79.50 (15%)

This product is vehicle specific. Please to ensure fitment.

Learn More

Product Details

This product is legal in California only for racing vehicles which may never be used, registered or licensed for use upon a highway.

Resources

Two Brothers S1R Exhaust System Honda GROM MSX125

The Two Brothers S1R Exhaust System represents a step into the future for TBR. The S1R exhaust features a carbon fiber sleeve highlighted by a natural aluminum outlet and stamped, spring-mounted inlet for the ultimate durability. Like most TBR mufflers, the end cap of the S1R exhaust is constructed of magnesium and features a non-stick teflon coating. However, that is where the similarities end.

The aggressive design of the end cap is reminiscent of the modern jet engine making this exhaust move at mach 1 speeds while standing still. The carbon fiber sleeve of the S1R exhaust system is made of a 33 million modulus rated carbon fiber that is impregnated with high temperature resin, under very tight tolerances. Thirty-three million modulus rated carbon fiber can be considered the Goldilocks of carbon fiber , it has strong structural properties without being overly stiff and brittle, making it just right.

The sound produced by the S1R is deep and throaty thanks to its spiral-wound perforated core technology. The rubber-lined, natural finished aluminum muffler clamps feature an aggressive angular design and cutouts to reduce weight. The mid-pipe is constructed from .035” thick 304 stainless steel. After a few heat cycles the 304 steel turns a golden amber color, the hallmark of quality stainless. Of course an exhaust can't be all show and no go, that is why the S1R exhaust is track-tested and dyno-tuned to offer the best performance package.

Features:

  • Fully-serviceable in the event of damage, routine maintenance or the occasional repack
  • Aerospace high-temp carbon fiber
  • Stamped spring-fit inlet
  • Optional P1 and PX1 sound inserts available (sold separately)
  • Optional anodized bolts kits available (sold separately)
  • Made in USA
Unit Stock Exhaust Two Brothers Max Gain
Max Power HP 8.65 9.5 + 8.5%
Max Torque ft-lb 7.64 8.04 + 8.5%
Weight lb 11.15 5.65 - 5.5
Made in the USA
Product Style RevZilla Item # MFR. Product # Availability
Product Style Carbon Fiber / Full System RevZilla Item #935688 MFR. Product #005-3740105-S1 AvailabilityIn Stock: Ships next business day

This product is vehicle specific. Please to ensure fitment.

This Product Fits
Honda
Grom MSX125 2014, 2015
This item is also available for 16 different bikes. View All Models
Honda
CBR500R 2016-2018
Kawasaki
Ninja 650 2017-2018
Ninja 650 ABS 2017-2018
Ninja ZX-6R 2009-2012
Ninja ZX-6R ZX636 2013-2018
Versys 650 2015-2018
Z650 2017-2018
Yamaha
FJ-09 2015-2017
FZ-07 2015-2017
FZ-09 2014-2017
MT-07 2018
MT-09 2018
R3 2015-2018
R6 2008-2018
XSR700 2018
XSR900 2016-2018

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Product Description
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Reviews & Questions

5.0 / 5.0
3 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
3
0
0
0
0
Bang For The Buck
5.0 / 5
Features
5.0 / 5
Style
5.0 / 5
Ease Of Install
5.0 / 5
Fit & Finish
5.0 / 5
Durability
5.0 / 5
Bang For The Buck
5 / 5
A great upgrade for the Honda Grom!
Overall I really like the stock look of the Honda Grom and never planned on making too many mods.

Visual:
When I saw the Two Brothers S1R Exhaust System, I thought it enhanced the look of the bike without radically changing any lines / characteristics. The choice of materials used and the simplified mounting really gives the bike a more premium feel. The carbon fiber looks sick in real life.

Sound:
My only concern was I did not want something obnoxiously loud. There are videos posted online of the sound you can expect from this exhaust, but it is hard to judge the volume.

Luckily, it is just right. The exhaust is louder but not extreme. It has a really gnarly growl to it. I feel like the noise definitely matches the Honda Groms attitude.

Performance:
The Grom definitely feels like a new animal with this exhaust installed. I feel like the chart is accurate with its performance claims.

What the chart can not summarize is how the new exhaust sound will also make you feel like you're going faster. Its truly awesome.

Conclusion
I without a doubt recommend this product. I feel it brings the Honda Grom to the next level in all aspects an exhaust system can ( sight, sound, performance).
February 25, 2014
Ride:
2014 Honda Grom MSX125
Bang For The Buck
5 / 5
Two Brothers Exhaust Honda Grom
Excellent Product. 15 minute install and that is including getting the tools out and putting them away. Significantly lighter then the OEM exhaust. The sound is fantastic and after a couple wide open freeway runs the bike easily broke into the 60mph range, routinely touching 65+ mph. Really opened the bike up and the sound is amazing!
March 10, 2014
Ride:
2014 Honda Grom MSX125
Bang For The Buck
5 / 5
Features
5 / 5
Style
5 / 5
Ease Of Install
5 / 5
Fit & Finish
5 / 5
Durability
5 / 5
Two Brothers S1R - 2015 Honda Grom
2015 Honda Grom - first road bike at 52yrs old - I wanted to increase performance/hp and after researching the many different types/styles of exhaust for my bike I settled on the S1R; It's significantly louder and sounds like a small Harley, but it's not too loud (close).

Overall, the Two Brothers S1R full system adds to the performance as well as the aesthetics of the bike.
July 31, 2017
Purchased
1 year ago
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 19 questions Browse 19 questions and 11 answers
Why did you choose this?
RevZilla Store
great reviews, sweet sounding exhaust
Cynthia A on Feb 9, 2017
its awsome an great price
yadira t on Apr 15, 2014
great reviews, sweet sounding exhaust
Cynthia A on Feb 9, 2017
Read lots of reviews, seemed like the best overall performance for price. I also like the sound of this pipe, and the look.
BuenosNoches on Apr 11, 2016
its awsome an great price
yadira t on Apr 15, 2014
Read lots of reviews, seemed like the best overall performance for price. I also like the sound of this pipe, and the look.
BuenosNoches on Apr 11, 2016
Do you need to get a new exhaust gasket with this, or does it come with a new one?
A shopper on Jul 22, 2014
BEST ANSWER: It does not come with a gasket, so yes you need to get a new one.
I have the fender delete kit and givi mounted carrier. Will this exhaust fit w the turn signal lamps ? 2015 Honda grom
Russell G on Apr 23, 2017
Do you need to get a new exhaust gasket with this, or does it come with a new one?
A shopper on Jul 22, 2014
23 Customer Reviews
23 5/5
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18 Questions & 8 Answers
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