Author Topic: CB750...So, is this how it is supposed to run?  (Read 21146 times)

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Offline mlinder

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Re: CB750...So, is this how it is supposed to run?
« Reply #25 on: October 10, 2007, 10:32:05 am »
MrBreeze, what intake and exhaust are you running?
Again, I'm about perfect at 125 mains with (slightly opened up) hm341's and pods... Also at sea level, more or less.
No.


Offline mrbreeze

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Re: CB750...So, is this how it is supposed to run?
« Reply #26 on: October 10, 2007, 07:45:28 pm »
138.5 mains and your lean  :o
You misunderstand......My needles are set to the 2nd to leanest position.
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Offline mrbreeze

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Re: CB750...So, is this how it is supposed to run?
« Reply #27 on: October 10, 2007, 07:48:32 pm »
MrBreeze, what intake and exhaust are you running?
Again, I'm about perfect at 125 mains with (slightly opened up) hm341's and pods... Also at sea level, more or less.
K&N pods and 4to 1 Kerker with cone piece but no baffle. I bought 130's but haven't tried them yet. It does fine with the 138.5's
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Offline motomotard

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Re: CB750...So, is this how it is supposed to run?
« Reply #28 on: October 10, 2007, 07:58:55 pm »
how can you tell what size your jets are? i cant tell just by looking at mine.

Offline seaweb11

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Re: CB750...So, is this how it is supposed to run?
« Reply #29 on: October 10, 2007, 08:22:17 pm »
When you pull them, they have numbers on them ;D

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Re: CB750...So, is this how it is supposed to run?
« Reply #30 on: October 13, 2007, 05:20:52 pm »
Alright...first I want to say thanks to those who contributed to my thread.  A wealth of knowledge is on this board and I am glad I now visit here.

Anyway...

I swapped the plug and it didn't change much, but then I pulled the bowls off the carbs again and the first one only had a few dribbles of fuel in there.  Turns out much of my problem was float levels. 

I reset the float as close as I could with a digital veriner caliper and now it runs completely different.  I popped in some new plugs too and gapped them at .027" 

Then I hit the TON in 3rd gear and fast.  Bike is awesome to ride now and only needs a few other items to make it all good.  I'll be putting on the pointless ignition and new wires soon too.  Now I need to figure out my sticky brake situation and get a new battery and we'll be ready for the open road.

Offline HondaMan

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Re: CB750...So, is this how it is supposed to run?
« Reply #31 on: October 14, 2007, 08:52:46 am »
Great info Hondaman(as usual). My 75 K as far as I know is internally butt stock. I have done alot of work on it since I bought it in 2000 and moved it from 5000 ft. to sea level. I bought it in Wyoming April 2000 with 14K miles. Here it is getting on to 8 years later and I just cracked 20K last week!!!! I would entertain your comments on newer electronic ignition and also CR carbs. I have the Dyna 2000 but still runnin stock carbs (138.5 mains-needle at 2nd from top.....almost lean). I guess I'm starting to feel a little envious after the surge of bookoo buck overhauls recently (Sean,Sparty, Gordon,Sam,etc.).My overall plan at this time is to keep this one running as much as possible and find me one to tear apart and put back. I don't care if it takes a few years to do but I want it to be powerful,clean,and of course....very carefully thought out....

That jetting seems strange to me.  ???

At this altitude, I'm running 100 mains with the needles at 2nd from bottom notch. This setting works very well on 85-87 octane with X24 plugs, slowly fouls D8 plugs. Running in the middle notch makes it just barely lean at 3/4 throttle, and the acceleration is less, noticeably. At 2nd notch from top, it hesitates on acceleration and 3/4-to-full throttle comes on like a shot when the needle clears the jet. (Fun, but not quite right, feels like a Kaw Blue Streak coming "on pipe" when it's that way  ;)  ).

How did it come to this jetting?
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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