Jump to content

Beta REV3 popping.


daveblackburn
 Share

Recommended Posts

Hi,

I picked up a couple bike for my spouse and I. A 2009 evo 290 and a 2007 rev3 270. The rev3 has a loud popping/snap from the exhaust at idle. The evo sounds great. and is not loud. I repacked the muffler, replaced all the o-rings and checked the complete exhaust for leaks. Is this just how the rev3 sounds? It's really loud and my spouse doesn't like riding it because of it. I also tried dialing in the carb. Didn't help. Any suggestions? Thanks, Dave

Edited by daveblackburn
Link to comment
Share on other sites

 

 
 
 

Has anyone come up with a way to quiet them down a bit?  I have a new to me 2001 Beta 270 Rev 3 that looks brand new with almost no hours on it.  I pulled the muffler apart and the packing looks brand new.  Still, it is pretty loud.  It probably does not help that it has a spark arrester shaped a little like a megaphone.  I would really like to quiet it down a bit.  The only thing I have heard of is to reduce the flow diameter with a reducer where the mid muffler meets the rear muffler but I have not tried it yet.  It does look like one the universal FMF mufflers may fit in place of the original but I don't know if it would be any quieter. 

Link to comment
Share on other sites

 
 

Does your wife need a 270?

The smaller capacity Revs , 125 or 200, pop less, are quieter and in an inexperienced riders hands, possibly a better bike.

If she doesn't want to ride it, consider a smaller capacity one, you want the noise to put her off riding trials!

Link to comment
Share on other sites

 
8 minutes ago, jonboy883 said:

Does your wife need a 270?

The smaller capacity Revs , 125 or 200, pop less, are quieter and in an inexperienced riders hands, possibly a better bike.

If she doesn't want to ride it, consider a smaller capacity one, you want the noise to put her off riding trials!

I agree. Very limited options where I live right now. She's used to riding bigger bikes and does ok. Just being picky about the noise. We were trying to find a 200, but no luck. This 270 is in great shape and the price was right!

Link to comment
Share on other sites

 

The world guys used to stuff steel wool into the silencer for sound test. The Betas are a fairly high compression engine which is why the need for high octane fuel. Also why you get that pop when the exhaust port opens. Restricting flow in the exhaust will slow down the top end of the engine as well as make it quieter. You could try blocking some of the holes in the silencer core to achieve this. A piece of thin sheet metal should suffice. Alternately you could buy a low compression head to reduce the pop and the need for race gas.

One thing to keep in mind though is despite how loud it seems standing behind the bike the sound of trials bikes doesn’t seem to carry. Honestly. Losing track of your friends in the woods is a common problem as if you can’t see them you usually can’t hear them. Only know where they are when they yell.

 

  • Like 2
Link to comment
Share on other sites

 
 
  • 1 month later...

I had a some success quieting down an 2001 270.  It is not a night and day difference but there is a noticeable decrease in sound.  The bike had a megaphone shaped spark arrestor and 
I swapped it out for a John Deer style.  The link shows the type but I'm not sure it is the exact size.  There are 2 or 3 sizes. 

https://www.ebay.com/itm/Lot-of-2-NGP-49024-AM108146-Exhaust-Muffler-Spark-Arrester-Screen-Type-1-3-8-OD/162488243183?hash=item25d50dd3ef:g:2NIAAOSwWWxY~Wzt

Second, I put on a rubber 90 degree elbow on the end of the exhaust so it points at the ground.

 

 

 

 

   

IMG_4129.JPG

  • Like 1
Link to comment
Share on other sites

 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
  • Create New...