BikeMaster Rubber Muffler Plug

$3.99 - $4.99
4.50 5 15
4.50 out of 5 stars
BikeMaster Rubber Muffler Plug
BikeMaster Rubber Muffler Plug
  • Description
  • Reviews (15)
  • Q&A (6)

At BikeMaster, they understand the quality and performance that motorcycle owners demand. They also understand that quality should be affordable. Not just for professional riders and mechanics, but for the everyday rider / mechanic as well. That is why BikeMaster continues to bring that level of quality and performance to all riders with their complete line of tools, parts and accessories at affordable prices.

  • Protects the exhaust system from water during pressure washing.
  • Keeps humidity from entering pipe as it cools down or prevents condensation inside the pipe during storage.
  • Formulated to be stiff enough to not fall out but soft enough to insert into the pipe without damage.


  • Small:
    • Minimum diameter of 14.75 mm / maximum diameter of 37.75 mm.
    • Fits most 2-stroke applications.
  • Large:
    • Minimum diameter of 33 mm / maximum diameter of 61 mm.
    • Fits most 4-stroke applications.
4.5 out of 5 stars (15)
4.5 out of 5 stars
5 star   14
4 star   2
3 star   2
2 star   1
1 star 0
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1-10 of 15
Overall 5 out of 5 stars
Verified Purchaser
Didn't fit, but...

I purchased the large (which states it fits most 4-stroke applications) muffler plug for my stock four-stroke 2002 Raptor 660R and it didn't fit. I then contact a MotoSport representative about my issue and they told me they'll send me a smaller muffler plug for NO charge. Amazing customer service. Thank you guys once again at MotoSport!

Overall 5 out of 5 stars
Verified Purchaser
Location: Michigan
Plug Perfect

Bought two of the small size, they fit my stock KTM four stroke muffler as well as my FMF muffler on my two stroke. Nice, cheap and get the job done.

Overall 3 out of 5 stars
Verified Purchaser
Did not fit 2002 ktm 250 exc race four stroke

this plug did not fit in exhaust pipe . it would be helpful to have the dimension of this plug in the description so one could measure there exhaust before ordering

Overall 5 out of 5 stars
Verified Purchaser
Does the Job

The small fits nicely for the KTM 85sx, it does what it's suppose to.

BikeMaster Rubber Muffler Plug
Overall 5 out of 5 stars
Verified Purchaser
Location: Touchet, WA
Nice to have when washing bike

Fits in perfect in my pro circuit four stroke exhaust. Can wash my bike with out having to worry about getting water in the exhaust. Just remember to take it out before trying to fire up the

Overall 5 out of 5 stars
Verified Purchaser
Location: Comanche, tx
Exactly what the doctor ordered

I have a 2000 Yamaha XVS650 with Cobra exhaust and the large plugs fit great. I also have a 2007 Honda VT1100C with stock exhaust and the small plugs fit this bike great. Where I live at the lake we always have problems with dirt dauber wasps that build nests everywhere. At least they won't be building nests in my exhausts.

Overall 3 out of 5 stars
Verified Purchaser
Please Include Actual Measurements in Description

The sizing on this item is incorrect, or at the least, lacking in any relevant detail. "Small fits most 2-stroke applications, Large fits most 4-stroke applications." That's it. I have a Suzuki DRZ-400S which I would consider a fairly common 4-stroke. The "large" plug is much, much too big for the stock exhaust.

For what it's worth, the plug starts at approximately 1 5/16" (33mm) and ends at 2 3/8" (61mm)

Unfortunately, it's not worth the cost of shipping to return.

Overall 5 out of 5 stars
Verified Purchaser

Small size is perfect for a 2 stroke exhaust

Overall 5 out of 5 stars
Verified Purchaser
Location: Kinston ,NC
Getting it Done

Does exactly what it is intended to do.

Overall 5 out of 5 stars
Top 1000 Contributor Verified Purchaser
Location: Fort Dodge, IA 50501, USA
Exhaust Plug at a Great Price

There really isn't much you can say, the plug works as it is supposed to. I have a 250 and a 450 and this works great and fits in both perfectly. With the cone shaped varying rings it should fit almost any 250-450 4 stroke application. Just remember to pull the plug before you go to start, haha. I thought my bike sounded a little different.

These plugs are a must, without them you water can get into places you don't want.

1-10 of 15
Total Questions (6)
Questions with answers:
Questions without answers:
Which one?...
cr85tamer Location: Esterhazy, SK S0A, Canada
1-6 of 6
Honda23 4 months 8 days ago
What is wrong with my exhaust/Dirt Bike?
I had just bought this product about two weeks ago and place it in my exhaust when I am not riding. I went to ride my dirt bike and when I started it took about 7-10 tries to start it up. It usually does this, but it is probably me because I am still kinda learning how to start it properly with giving just enough throttle. After 5 seconds of it running I see smoke coming from between the engine and the Fatty Pipe. So I turn it off right away and see I still have my muffler plugged in. I have a 1997 Honda CR125 2-Stroke and I am used to it smoking a little because it's a 2-Stroke, but now it's smoking a lot. It also leaks exhaust oil between the Engine and the Fatty Pipe, and also between the Fatty Pipe and the Muffler. I rode it a little on our property and realized it has lost a lot of power now and it shuts off when I hold in the clutch to brake. What is wrong and what would I need to do to fix these two problems?
MotoSport Staff Expert
4 months 5 days ago
It sounds like your 1997 Honda CR125 is running rich. I would check your jetting and fuel pre mix ratio. Pull the spark plug out and see how it looks. How many hours are on the top end of your CR125? Feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
1 month 14 days ago Location: Hunt, NY 14846, USA
I can't tell you exactly what the problem is. But if I were you, I would go find a near by magazine rack and pick up a copy of ATV rider and look for the section called (ask Mikey). Several people send him questions about mechanical issues with their machines and he has a very good reputation for giving good advice on making repairs. You are probably not the first person to have that happen to that particular bike. Hope that this is helpful. Good luck!
JesusM Over 12 months ago
What size would fit on the Honda CB300F ?
Top 1 Contributor
Over 12 months ago
The CB300F is a 4 stroke engine, thus select the 4 stroke plug. It will fit best for your machine.
Charlie 1 year 5 months ago
Will the plug fit my 03 kx 125 pro circuit platinum silencer?
Expert MotoSport Staff Top 1 Contributor
1 year 5 months ago
Yes, you will want to go with the size Small BikeMaster Rubber Muffler Plug for your 2003 Kawasaki KX125.
crf250man 1 year 7 months ago
Which one?
I have a 2014 crf250r with the dual exhaust. The holes on it I believe are smaller than a single exhaust. Should I get the big muffler plug or the small one?
Top 1 Contributor MotoSport Staff Expert
1 year 7 months ago
For your 2014 Honda CRF250R with the dual exhaust you can go with the large but may have to trim to fit so I would recommend going with the small.
Ryan66 2 years ago Location: Michigan, USA
It doesn't seem like it seals my stock YZ125 exhaust. It wiggles around. Is that normal?
When i put the plug in my 2012 Yamaha YZ125 stock exhaust it seems like it goes half way in but yet I can still wiggle it around alot. Is that how its suppose to be or is it not sealing properly?
MotoSport Staff Expert
2 years ago Location: Portland, OR, USA
For that Yamaha YZ125 you should be using the Small Sized muffler plug. Yes because of the way the plug is made you are going to be able to move it around when it is in the muffler. If the plug is inserted as far as it can go the "ridges" on the plug should seal out any water or debris when washing your bike.
cr85tamer 2 years 9 months ago Location: Esterhazy, SK S0A, Canada
Would the small fit a procircuit r304 silencer the fmf does not??
MotoSport Staff
2 years 8 months ago Location: Portland, OR, USA
The small is designed for 2 stroke silencers so it will fit your Pro Circuit R304 no problem.
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