Topic: Newbie, Carb Jet question, I know I'm not the first

[tooth slayer]

Hey Guys,
very excited to join you.  first timer here. 
Purchased 1978 Honda CB550K for a Cafe Racer tear down, build.  Totally stock when I bought it 3 weeks ago.  Never done before but already tearing this baby down.  NO leaks, overall in good shape.  41K miles.  No smoke.  Engine was running rough.  Guy I bought from only owned it for a year and never was on it.  Previous owner bought it new.  He did a carb rebuild, so I was told.  Idle rough, better when warm, choke makes better.  So I was on to checking carb despite the "don't touch the carbs" suggestion.  Found Main jet was 90 and the slow jet doesn't appear to be able to remove, no flat head on top, just smooth barrel.  I broke out the manual (which I was lucky to get) and says main jet should be 100.  I just removed the old air box, (ugly and bulky) for...yes, air pods.  Love them or not I like the appearance. 
....so, what main jet would you recommend?  I read on jetsrus.com and they said increase 2 sizes from stock after their math.  No exhaust upgrade yet, still stock 4 separate pipes.  I live at 3500 ft elevation.  stock should be 100.  Two up is 105.  ??
thoughts on OEM vs OEM equivalent on jetsrus.com???

[Scott S]

 Don't throw away the air box parts.

[jonda500]

Don't throw away the 4 into 4 exhaust system or any other oem parts either and look into cafe racer designs that don't involve cutting up the frame unless you're ok with upsetting those of us who highly value the oem stock parts,
John

[TwoTired]

Doesn't matter what the stock jetting is if you aren't using the stock mufflers and air filter.  The carbs were tuned for those component's breathing characteristics.

The pilot jets ARE remove-able.  Grab them and pull them out of their press fit bores. If it has issues idling without choke, some pilot jets are likely plugged up.

Pods are not a specification.  They are a style description.  Pity that the bike doesn't run on a style description.  The air flow and pressure drop of "pods" are undefined and vary among offerings.  Predicting specifics of carb retuning is impossible.  Either try and test or pay for dyno time to correct your meddling with the bikes breathing characteristics.

Not that it matters much, but the manual you have is wrong if it says stock main is 100.  The PD style carbs for the 78 550 use 90 mains.  Honda provided a supplement to their manual covering the K3 version of the 550. Best to get a copy of that as you will be inside those carbs a lot while sorting out your pod modifications.

Oh, and do save all those original parts you loathe.  Restorers need them to convert cafe racers back to stock.

Cheers,

[tooth slayer]

I'm keeping all the originals.  my wife frequently tells me I'm a pack rat

[tooth slayer]

will do.  thanks for info on pilots. 
the input from people will be very helpful and much appreciated.

Cheers

[BomberMann650]

Later years had smaller mains

[Deltarider]

Go to http://forums.sohc4.net/index.php?topic=17788.0 : and scroll down to: Honda CB500 CB550 CB 500 550 Workshop Service Repair Manual 1971 - 1978 Part 10 p.175. See pics below for carb identification and how to remove pilot jet.

[Killer Canary]

Quick question; are the press in pilots available in different sizes, and who carries them if so?