Author Topic: Big intake heads from Cycle X  (Read 7077 times)

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Offline dragracer

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Re: Big intake heads from Cycle X
« Reply #50 on: January 08, 2021, 06:38:40 pm »
I think I'm going to contact Kenny soon to ask about the I.D. and O. D. of the spigots on his modified head. At this point, I don't feel I can break into the 9's without more airflow. I'm trying to avoid installing a stroker crank to achieve this goal.
How big is your motor now, Frank?
we q
I think I'm going to contact Kenny soon to ask about the I.D. and O. D. of the spigots on his modified head. At this point, I don't feel I can break into the 9's without more airflow. I'm trying to avoid installing a stroker crank to achieve this goal.
How big is your motor now, Frank?

It a 1030cc K headed engine with high compression pistons.

Offline scottly

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Re: Big intake heads from Cycle X
« Reply #51 on: January 08, 2021, 06:47:53 pm »
Yeah, some good head might put a smile on your face. ;)
Don't fix it if it ain't broke!
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Offline Medyo Bastos

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Re: Big intake heads from Cycle X
« Reply #52 on: January 09, 2021, 05:43:37 am »
Yeah, some good head might put a smile on your face. ;)
Or several others, too


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Offline dragracer

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Re: Big intake heads from Cycle X
« Reply #53 on: January 09, 2021, 10:36:08 am »

How many good heads are you storing under the bed Medyos. Lol
Yeah, some good head might put a smile on your face. ;)
Or several others, too


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Offline dragracer

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Re: Big intake heads from Cycle X
« Reply #54 on: January 10, 2021, 04:08:58 pm »
Looking for a 9 second pass and trying to eclipse 125mph.

Offline scottly

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Re: Big intake heads from Cycle X
« Reply #55 on: January 10, 2021, 09:48:32 pm »
How much work has been done on your K head, Frank? Have you had the bike on a dyno recently?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline dragracer

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Re: Big intake heads from Cycle X
« Reply #56 on: January 10, 2021, 11:50:39 pm »
How much work has been done on your K head, Frank? Have you had the bike on a dyno recently?

Head has been ported. New  33.5/28.5 SS valves with HD strings.  Rc 327 cam. Large intake boots with 34mm Mikuni flatslides.

Bikes not been dyno'd yet. I do plan to install a Wego so I can data log my AFR in real time. I  need to be certain my jetting is correct. 

I can easily get this bike into the mid 9's if I decide to spray it. It just a major putting a fresh nitrous bottle in the bike and programming my nitrous tuneup. 

Offline PeWe

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Re: Big intake heads from Cycle X
« Reply #57 on: January 11, 2021, 12:43:51 am »
Other cam that can improve?
CB750 K6-76 1005cc JMR Billet block.
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 dragracer

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Re: Big intake heads from Cycle X
« Reply #58 on: January 11, 2021, 10:19:36 pm »
Other cam that can improve?

PeWe. I haven't given much thought to a cam change because this is a drag only engine. The cam is for mid to high rpm range for larger cc motors. Lift and duration should be perfect for my setup.  I do have a larger RC 454 cam I could try but its doubtful I would gain anything with the size intake valve and ports I've got now.

Offline PeWe

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Re: Big intake heads from Cycle X
« Reply #59 on: January 12, 2021, 12:43:07 am »
Kenny Harmon Super F
Megacycle has alternatives too as CycleX has.
You or friends of yours might have tested before what these cams can do vs RC327?

Sam's Auto ran nice on the DP295 with good IN lift. ;)
CB750 K6-76 1005cc JMR Billet block.
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