[Everett45]

As the title states I want to look into getting rid of this H box... Mine is pretty well rusted out. Yes I've read it's critical to performance and scavenging. I just want to know how in-depth it would be for me to replace it with straight pipes and new mufflers. Other than new jets, what are the other adjustments people speak of?

 

[J-T]

Sounds like you may have already read this but just in case:

http://www.hondatwins.net/forums/67-miscellaneous-discussion/41350-power-chambers-explained.html

Short answer is re-jetting is really all you can do. Even when you get them "right" it's unlikely you'll be able to duplicate stock performance but, with the availability of replacements, it may well be your best choice.

 

[CBSigmund]

Would you consider getting a balance pipe added by an exhaust shop? I made my own exhaust and added a balance pipe to it. It might be the same as standard, but my bike runs perfectly through the rev range.

 

[longdistancerider]

A balance pipe helps some but doesn't take the place of the power chamber. It serves more as a noise cancellation device.

 

[CBSigmund]

A balance pipe helps some but doesn't take the place of the power chamber. It serves more as a noise cancellation device.

What is a noise cancellation device? The power chamber?

 

[longdistancerider]

The exhaust gasses will expand into the balance pipe which cancels out some of the sound. Typically you'll loose some of the annoying high frequency sound.

 

[Old Okie]

It may be because I am thrifty, some call it cheap, but I choose to keep stock air box and H box on my bikes.
All these mods are more trouble that they are worth, in my opinion. However my '79 CB400T is currently running
straight off the H box with some chrome exhaust tips meant for a car or truck. Sounds OK until I decide what
I really want to put on it. My CX500 had gutted stock mufflers with the H box and it is not loud at all.
There again, cheap or thrifty???

 

[Polish]

I'm with Old Okie here. Cheap, no trouble, no rejeting and looks good to me. Just time and little bit of paint.

 

[DD23]

You know of the MOTAD 2 into 1 system, less than half the weight of the oe system, no performance issues and looks good too.

 

[DD23]

Yes, a straight thru system with a collector junction below where the rear brake/kick starter would be, but the headers have a rolled "restriction" at this junction end. The silencer has baffles/chambers.

Note, the left header seems to suffer from corrosion quite badly but if your bike lives "inside", then they do not suffer so much.

I believe that MOTAD has gone bump ??

250 and 400 systems where made.

 

[longdistancerider]

Motad is alive and well, David Silver Spares is the UK and US supplier