Since this weekend will be devoted to fix my 400cc, chain-driven 1990 black Savage, I'll try to get the Sportster muffler on it while I'll be at the bike's side.

Question is, being a 400cc, what should I do to the carb in order to accomodate the better flow and sound of a HD Sportster muffler I have to install?
Main jet? Idle screw?
Any idea is appreciated.

Take care,

RW

Red_Wine wrote on 12/31/69 at 16:00:04:


Since you have the only 400 Savage in the group (you have a real distinction), this one is new.  Certainly you don't have to do anything to accomodate the better sound of the HD muffler   but I do imagine that you'll have to think about the flow....and I imagine that new jets may be necessary.  Or an adjustment.  It would be neat if you could fill us in concerning the inside of your carb.  Jet size and jet needle on the 400 Savage are new subjects.

If you put on a free-flowing exhaust, even just a muffler, you should rejet and get a better flowing airfilter. Key word, should. I run an open exhaust on a 98 650, with factory jetting, factory spacer, dirty factory aircleaner, and the idle mixture screw out two or so turns beyond stock. Bike gets in the mid-70s to mid-80s miles per gallon with that set-up, and still carbons up the end of the exhaust pipe (yep, that long set-up in the pics is empty, no muffler guts). Plug still is a nice tan to slightly brown color. I do have to run premium fuel in it though.

Follow the pics. Carbs likely aren't the same, but should be similar.
-WD

Greg,
right now, I have no clue about the carb size or jet sizes. I'll find out once I get to the carb tomorrow.  

I understand your fuel to air ratio stuff, and yes, with the HD muffler more air will flow through the engine, and therefore I should put more fuel into it in order to mantain the F/A ratio, right?

That means, I should open the fuel screw passage or wathever that is called, right?

Anyway, if I screw up and cann't get the bike to start after all the mess, I can put it back to present condition, and write to you for solutions  

Thanks,

RW

Hi fellas,

an update on the current development.  

The muffler swap did not work.   I pulled the existing pipe (an ugly doobie-like muffler) and the bracket off the frame, tried to get the HD muffler on, but I realized that I needed to get a completely new support setup for that.  ???  So I took some measurements, sketched a bracket, but got stuck with no welding shop open Saturday evening (not to mention Sunday).   My father had sold his Oxi-Acetilene kit, so I'm stuck until later in the week.  

Since riding the bus to work is a no-no, and driving the cage involved a huge bill in parking, I just let the header on, bolted a chromed tip, and fired her... WOW!!! it is d***med LOUD!!!    

So far, no jetting was needed altough it tends to "cough" on take off at stop lights, and BIG LOUD FARTS are coming out the back on deceleration...  

I'll get ear plugs today for the ride back home, otherwise I could get permanent ear damage  

I'll have the bracket cut and welded today or tomorrow, coat it with black paint, bolt the HD muffler by the weekend, and see what happens  

I'll kep you posted, pictures are on the way, just need to expose the complete film, (probably a weeked job  )

Take care,

RW

Lion...  This thread is a year old...  You might want to email  red_wine direct... Click on his name for his email address......

Well Lion,

I just had to change the jets one size bigger, and the new (not new anymore, it's been there for a year) HD muffler is just great.

No farts, just a very small "poof" when killing the engine, that's all I get..Good luck.

BTW, where are you with your 400cc Savage?

Best,

RW

Never mind neither do I