Author Topic: Delkevic & K6, pilot jets?  (Read 271 times)

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Offline Magpie

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Delkevic & K6, pilot jets?
« on: January 03, 2025, 08:19:14 AM »
I recently installed a Delkevic 4 into 1 on my K6, a friend suggested I go to 42's for pilot jets. Not good.
I'm curious what size of pilot jets other Delkevic owners are using.
Thanks,
Cliff.

Online newday777

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Re: Delkevic & K6, pilot jets?
« Reply #1 on: January 03, 2025, 08:39:06 AM »
Bone stock K6 or???
Stu
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My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
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Offline Nurse Julie

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Re: Delkevic & K6, pilot jets?
« Reply #2 on: January 03, 2025, 09:16:53 AM »
Jetting doesn't need to be changed when fitting the Delkevic systems as long as standard airbox etc is still being used. .
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Offline beemerbum

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Re: Delkevic & K6, pilot jets?
« Reply #3 on: January 03, 2025, 09:41:20 AM »
Jetting doesn't need to be changed when fitting the Delkevic systems as long as standard airbox etc is still being used. .
+ I found that to be true on my K7. It runs perfectly with the Delkevic that replaced the original system. Plugs showed ideal mixture with stock airbox
« Last Edit: January 03, 2025, 09:42:59 AM by beemerbum »

Offline BenelliSEI

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Re: Delkevic & K6, pilot jets?
« Reply #4 on: January 03, 2025, 09:44:14 AM »
Cliff…. When I had a Hindle pipe on the ‘75 750F (standard airbox/filter) it ran really well with stock jets. I doubt the Delkevic is any different…..

Offline PeWe

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Re: Delkevic & K6, pilot jets?
« Reply #5 on: January 03, 2025, 10:16:57 AM »
My K6 wirh 836, ported head, cam, a loud 4-1 and stock carbs with pods had stock pilot jets, 40.

Needles at 4th notch from top, 3rd was stock. Plus pods.
So pilot jet is fine stock.
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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: Delkevic & K6, pilot jets?
« Reply #6 on: January 03, 2025, 10:30:22 AM »
Cliff…. When I had a Hindle pipe on the ‘75 750F (standard airbox/filter) it ran really well with stock jets. I doubt the Delkevic is any different…..
That model has good carbs. 064A.
My K2 got a set 2023. Work better than my old 086A (K6).
I think it is the 064A's needle taper that differ, a little richer.

My K2 has K&N filter in K6 stock airbox and good flowing Yamiya no number 4-4.

The K6 carbs must have needles at 4th notch, 064A at 3rd.
Main jet 115.
I updated the 064A last summer with 120 for better high speed response.
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 HondaMan

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Re: Delkevic & K6, pilot jets?
« Reply #7 on: January 03, 2025, 10:56:29 AM »
Cliff…. When I had a Hindle pipe on the ‘75 750F (standard airbox/filter) it ran really well with stock jets. I doubt the Delkevic is any different…..
That model has good carbs. 064A.
My K2 got a set 2023. Work better than my old 086A (K6).
I think it is the 064A's needle taper that differ, a little richer.

My K2 has K&N filter in K6 stock airbox and good flowing Yamiya no number 4-4.

The K6 carbs must have needles at 4th notch, 064A at 3rd.
Main jet 115.
I updated the 064A last summer with 120 for better high speed response.

Your comment about the 086a matches my experience with them, too. I wrestled with a set of them on a 750F1 some 10-12 years ago. What I found was interesting and unexpected: several of the idle-air passageways between the idle air inlet jet (at the back of the carb, in the bell) were corroded partway closed and those 3 carbs ran dead lean, well past even what a #45 idle jet could wet down: there just wasn't any airflow coming in those ports to the idle-mix screws. The bike came from [salty] Florida where it was parked in a garage, but near the beach, for 4 years, and had been running during the years of MTBE gasolines here in Colorado before then. In the end it became a tricky exercise of removing the tiny brass idle-mix-air orifices at the back of the carbs, cleaning the passages up to the air screws, then restaking those tiny brass holes back into place. Then the stock #40 idle jets worked fine in all 4 carbs, for the years since. Without airflow in those air ports thru the idle-mix screws, there is no fuel flow, either.
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Offline Magpie

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Re: Delkevic & K6, pilot jets?
« Reply #8 on: January 03, 2025, 04:43:42 PM »
Thanks guys!
It's a stock K6, standard air box.
When the 1100F comes on the lift the K6 will get the love, back to 40's, needles to 4'th notch from top, another clean  and balance.
God I love this forum!  :D
Cliff.