Author Topic: Need a cam card for a Megacycle 125-75 cam  (Read 1091 times)

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Offline gschuld

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Need a cam card for a Megacycle 125-75 cam
« on: June 05, 2021, 06:02:45 AM »
Anyone have specs and or recommendations for proper set up.

1025cc
10.5:1 compression
Ported head
29 carbs

Thanks,

George

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Need a cam card for a Megacycle 125-75 cam
« Reply #1 on: June 05, 2021, 09:33:35 AM »
Well of course. PM your phone number and I will text it to you.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline gschuld

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Re: Need a cam card for a Megacycle 125-75 cam
« Reply #2 on: June 05, 2021, 09:57:12 AM »
Thanks man👍

George

Offline PeWe

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Re: Need a cam card for a Megacycle 125-75 cam
« Reply #3 on: June 05, 2021, 11:58:21 AM »
Satanicmechanic.org spec
125-75 (125-70)
lift/dur/LC
IN  .400     262   105   
op/close @0 lash / rec lash
26/56    .005

EX .375      257   104.5
53/24   .005

My timing last year with a 125-75 ( billet cam)
Note! I hade to file cam holders, lobe contact.  I made sure at least 0.25mm clearance.

Ported K2 head 34/28mm valves. 101whp setup on dyno Sept/Oct -2020
Lift In/Ex: 10.0/9.4mm
Open close at 0 lash, 1mm lift:
26/55      dur: 261
55.5/23  dur: 258.5

This year a 392 head 33.5/28.5mm valves.
A little bit later to wish for HP to continue after 9000 rpm ;)
@ 0 lash
IN: 24.5/56.5*
EX: 54/24*

It runs really fine, idle as a stock bike except for it ponds harder due to higher compression.
+195PSI with a cheap tester.
(stock fresh 736 145-150PSI with same tester)

I set valve lash to:
In:  0.1mm
Ex: 0.15mm
« Last Edit: June 05, 2021, 12:10:14 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 gschuld

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Re: Need a cam card for a Megacycle 125-75 cam
« Reply #4 on: June 05, 2021, 04:03:05 PM »
Awesome. 

Thanks Per.

George

Offline PeWe

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Re: Need a cam card for a Megacycle 125-75 cam
« Reply #5 on: June 06, 2021, 12:03:01 AM »
Mike must have timing experiences of this cam for various needs?

It will be very interesting to hear how this history will continue! ;D
Dyno chart in blue (101 whp) with 125-75 last year. In open at 26* 1mm (0.04") lift,  0 lash.



« Last Edit: June 06, 2021, 07:46:53 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