Author Topic: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65  (Read 6734 times)

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Offline brandEn

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #25 on: September 27, 2013, 07:53:01 AM »
found em
http://www.knfilters.com/search/product.aspx?prod=rc-2314

I can get a set of 4 from Amazon for under $100

Offline Medyo Bastos

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #26 on: September 27, 2013, 08:52:20 AM »
the first thing i noticed was no more goofy sucking sound you hear with cheap pods!

Offline Retro Rocket

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #27 on: September 27, 2013, 04:05:54 PM »
the first thing i noticed was no more goofy sucking sound you hear with cheap pods!

I hate that sound, sounds like  4 cylinder blow job..... :o 8)
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline PeWe

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #28 on: September 28, 2013, 06:17:55 AM »
Nice sound :-) If you hear the inlet that much your 4-1 must be too silent :-)
All years with 4-1 made me to miss the 4-4 pipes and the wonderful sound during deceleration.
Well made 4-4 set would be fine. Shorter ones with racing look and good breathing, maybe stainless steel.....

EDIT: I had to visit my garage and open my old dirty carbs to check.
A little bit more than I thought.
Mains 147.5! 
pilot 40
Air screws  1/2 turn out.
I remember that I checked the mains at full speed and reduced throttle just a little bit. If the bike accelerated by reducing the throttle I changed mains to bigger. Also checked the plugs, kill switch at full speed.... The bike went well, mostly long touring vacations to north Italy, Spain with 2 much younger and slimmer persons + bags with luggage + tent_sleeping bags.
3 holidays. High speed all days long, mostly 150-200km/h according to the speedometer. I have blurry memories when driving in heavy rain passing trucks on Autobahn in Germany, could not see that much, reduced speed and saw the needle at 160-170km/h :o

If I should use the carbs today, I should upgrade the pilots and test the mains again.With gasoline of today with extra ethanol it might be OK and not too rich.

I hope my VM29's are not too lean, only 127.5, pilots 25, otherwise as CB750 spec.  Maybe I'll upgrade to 130.
« Last Edit: September 28, 2013, 02:09:28 PM 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 PeWe

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #29 on: September 28, 2013, 09:01:04 AM »
Oval KN filters today. Maybe better flow when they are bigger?
These fits the VM29's
http://www.knfilters.com/search/product.aspx?prod=rc-2454
« Last Edit: September 28, 2013, 02:07:52 PM 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 wiskey

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Re: CB750 stock carbs with headwork, Wiseco 836, and Megacycle 125-65
« Reply #30 on: October 03, 2013, 06:34:53 AM »
I believe they are the same ones i used. I have stock '77 carbs and similar engine build.
Without a dyno or A/F meter I have no idea how close my tuning is, with that said  I think I'm pretty close.

One tip I can give is how much of a difference a re-oil with K & N filter oil made to my bike. I'm sure many will point this out as a lean condition but carb #1 and #4 do seem to dry out much quicker. A quick spray and the bike just runs and sounds much better.

Also get the Morgan Carbtune. It's expensive (~$100usd) but a very nice kit and I contribute a lot of how my bike runs to having the carbs properly synced.