Author Topic: Re-installing Stock Airbox? Parts?  (Read 1034 times)

0 Members and 1 Guest are viewing this topic.

Offline neurotoxin312

  • Hot Shot
  • ***
  • Posts: 278
Re-installing Stock Airbox? Parts?
« on: April 09, 2015, 09:43:12 AM »
I'm trying to get a stock air box system back on my bike after I purchased it with pods. Bike idles fine and runs great IMO but I'm trying to see if things will actually be better with the stock system. I currently have a 4-1 exhaust and the carbs are jetted. Where will I see the biggest improvement with using the stock airbox over the pods if correctly jetted?

More importantly, how many parts do I need to get everything back to stock? (1) Airbox (2) filter

Offline Davez134

  • Expert
  • ****
  • Posts: 1,485
Re: Re-installing Stock Airbox? Parts?
« Reply #1 on: April 09, 2015, 09:47:36 AM »
What bike and year?

I go to cmsnl.com, pull up the bike/year, then look at the parts fiche to see what is needed.
« Last Edit: April 09, 2015, 09:55:37 AM by Davez134 »

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,546
  • Bike almost back to the 70's 2015
« Last Edit: April 09, 2015, 10:46:17 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline evanphi

  • Apparently I'm an
  • Old Timer
  • ******
  • Posts: 3,107
  • Rhonda the Basket Case
Re: Re-installing Stock Airbox? Parts?
« Reply #3 on: April 09, 2015, 10:05:40 AM »
Regardless of bike and year... if the bike was running properly (proper mixture at all throttle positions) with the pods, you jetting is likely to be overly rich now with the airbox on due to restricted airflow. If it was running with lean symptoms, putting the airbox on may help. :D
--Evan

1975 CB750K "Rhonda"
Delkevic Stainless 4-1 Header, Cone Engineering 18" Quiet Core Reverse Cone, K&N Filter in Drilled Airbox
K5 Crankcase/Frame, K4 Head and Cylinders, K1 Carbs (42;120;1 Turn)

She's a mix-matched (former) basket case, but she's mine.

CB750 Shop Manual (all years), searchable text PDF
Calculating the correct input circumference for digital speedometers connected to the original speedometer drive

Offline Toolmaker

  • Full Member
  • *
  • Posts: 29
Re: Re-installing Stock Airbox? Parts?
« Reply #4 on: April 09, 2015, 12:40:30 PM »
I saw a few people installing aftermarket filters on the back of their air boxes by making a special bracket to mount on the plenum. I've read a whole lot about it but nobody is saying how well it works. Or at least hours of searching hasn't found anything.

Offline Old Scrambler

  • My CB750K3 has been in 39 States & 5 Provinces
  • Old Timer
  • ******
  • Posts: 3,808
Re: Re-installing Stock Airbox? Parts?
« Reply #5 on: April 09, 2015, 02:23:34 PM »
The late-model units from K8 and F2-3 models are best for air-flow. On my K3 the stock box with a K&N filter liked 120 mains with a 4-1 exhaust. When I switched to stock exhaust it was a bit rich so now running 115s.
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
CB750 Classic Bonneville Racer thread - http://forums.sohc4.net/index.php/topic,135473.0.html
'63 CL72 Project(s)
'66 CL77 Red
'67 Triumph T100C
'73 750K3 Owned since New
'77 750F2 Cafe Project
2020 ROYAL ENFIELD Himalayan