Topic: HM410 Exhaust

[jsleeper]

Hey all,

My bike has a black exhaust hooked up to the header, says Honda HM410 on it - and it has baffles at the end.  Does anyone know anything about these?  Are these the stock mufflers that came with the bikes, an option, or a performance add on?  The bike has a mean sound - much much different than our 76 CB750F.  This is the Sandcast bike if anyone is wondering.

[PeWe]

as in this add then?
http://www.steelhorseclassifieds.com/ads/1977-honda-super-sport-750/
EXHAUST # HM410 HONDA AND IS ORIGINAL TO THE BIKE

[jsleeper]

That's the one, except black.  That leans me toward it being stock, but not 100% - especially because of how much louder and deeper the exhaust note is than our '76.

[2wheels]

That is the same exhaust my 78 F has on it.  So it is stock.
Mine has black (painted by me) headers and chrome muffler.

Mine is very quiet.  Even though some of the muffler internals fell out when I had it off.

[lucky]

That is the same exhaust my 78 F has on it.  So it is stock.
Mine has black (painted by me) headers and chrome muffler.

Mine is very quiet.  Even though some of the muffler internals fell out when I had it off.

QUOTE:

"Even though some of the muffler internals fell out when I had it off"

Doesn't that bother you??
How much fell out which pipes?
I would be finding out .

[2wheels]

lucky
Actually No.  By the way it is a 4 into 1 system.  The 4 headers have nothing inside them.
I don't know what is suppose to be inside the muffler when new.  But what came out was a baffle of some sort.

As far as performance, the plugs look good.  Carburetor balance is fine.  Power is good, gas mileage is good.
And it really is quiet, way better than the K0.

[jsleeper]

That is the same exhaust my 78 F has on it.  So it is stock.
Mine has black (painted by me) headers and chrome muffler.

Mine is very quiet.  Even though some of the muffler internals fell out when I had it off.

Is there a cap looking thing on the end of it?  Mine has one and there are screws and a weld holding it on.  Maybe that's what makes mine sound different.

[CB750F2]

That exhaust is the system supplied for the F2 and in unmodified form it is quiet but still sounds powerfull. I like the sound and have them on both of my F2s. One looks a bit "tired" but it is solid and functional. They can rust in hte area just behind where the muffler joins the header. This happened to one of mine but I was able to repair it and make it presentable and functionable. A new system would cost over $2000.00 from a Honda dealer here in Australia. Pat

[CB750F2]

I don't think the cap does anything - just there for looks I think. Pat

[2wheels]

Yes mine has the end cap.  Which I have taken off and painted black.
But as already said, I don't think it does anything for sound.

Also as above, mine had rusted where the header meets the muffler.  Someone did a really nice repair job with a piece of stainless steel.
I have only owned this bike for 2 years now.

[PeWe]

That is the same exhaust my 78 F has on it.  So it is stock.
Mine has black (painted by me) headers and chrome muffler.

Mine is very quiet.  Even though some of the muffler internals fell out when I had it off.

QUOTE:

"Even though some of the muffler internals fell out when I had it off"

Doesn't that bother you??
How much fell out which pipes?
I would be finding out .

Maybe as my 4-1 when I took it off after 20 years of no engine running. About 1dl granulated powder, brown stuff fell out. Probably the baffle that has corroded a lot and might be very thin today. I have to check closer if it will work or the pipes are too thin and I have to order a new 4-1 which will end up in $600US + tax for me =$800US :-(

[HonderCB]

stock exhaust for an F2/3.  Mine came without the end cap when i bought it and it is pretty loud and throaty.  I dont know if it is the end cap that quiets it down, or if i am missing another baffle somewhere, but i cant find another cap so it is staying the way it is for now (i think it sounds great, and isnt too loud if i stay out of it in town).  Bike is tuned to run great, so no issues with performance.