Author Topic: CB 750A --torque converter adjustments????  (Read 983 times)

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vulture7

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CB 750A --torque converter adjustments????
« on: July 23, 2009, 12:53:20 PM »
I fianlly took my cb750a for a ride today (to work) first since i bought it a few months ago. I have noticed when starting it on center stand even in neutral that the rear tire is moving pretty fast --- After warming up the bike it does not creep much at a stop sign -- just keeep the front brake on at a stop. There any adjustments that can be made? Or is this normal?

Bought this with fresh carb clean, new tires, chain, sprockets, winsdshield, and cables. Does need paint and seat covered.

Wayne (Wisconsin)

75 cb400F
78 CB750K
77 CB750F
74 CB550
78 GL1000
77KZ1000
74 CL360
73 CB350F


Offline Sam Green Racing

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Re: CB 750A --torque converter adjustments????
« Reply #1 on: July 23, 2009, 01:14:43 PM »
Welcome to the forum Wayne. There are a few A owners in here who will no doubt be able to help.
I have one but as yet have not seen it so can't offer any advise.

Sam. ;)
C95 sprint bike.
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Offline JLeather

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Re: CB 750A --torque converter adjustments????
« Reply #2 on: July 23, 2009, 02:49:20 PM »
It may be that your idle speed is too high.  The A is supposed to have a pretty slow idle speed, and then when you drop it in gear the dash-pot on the carbs kick the throttle up a hair so it doesn't stall.

There aren't any adjustments for the concerter without taking it out and apart.  I know guys who've dragraced A's and you can have the fins inside the converter machined down some to raise the stall speed (to like 4500 if need be) but that's extreme.  I suspect the idle isn't set correctly on your bike.

Also, it will always be worse when the bike's cold for two reasons.  First, when the choke is on your bike will idle faster (so it doesn't stall when cold) and second the oil is more viscous when cold so it will engage the converter at a slower speed.

CBdave76

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Re: CB 750A --torque converter adjustments????
« Reply #3 on: July 27, 2009, 02:35:00 PM »
Hello I have a 76 CB750A.
I am posting a reply late because I just got back from the AMA Vintage Days in Ohio. 
If you go to Hondamatic.net you can download the Service Manual in about 6 sections.  I have use this manual to help me with my bike.  I also added a tach to mine to see what the RPMs are at idle and in gear idle.  My wheel does the same thing while on the center stand.  I set the parking brake to adjust the in gear idle screw.  I then had to re-adjust it once the bike was "really" warmed up.  The automatic is the coldest Honda I've owned.  I have also replaced the 48 tooth rear sprocket with a 38 tooth.  This really lowers the RPMs at highway speeds, but it does take off slow.  I use "L" to start moving and then shift up to "D" around 40 mph.  I have only owned this bike for 3 months and just started riding it in July.  It had a frozen carb, frozen front brake, and broken coil wire connection when I got it.
David

Offline Spanner 1

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Re: CB 750A --torque converter adjustments????
« Reply #4 on: July 27, 2009, 09:07:36 PM »
+1 with Dave....I also just got back from AMA Vintage Bike Days!!
The 750A has 2 idle settings as described, set-up right there is no stumble or ' creeping' in Drive....manual explains it all........welcome to the Forum and good luck with your A.
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

vulture7

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Re: CB 750A --torque converter adjustments????
« Reply #5 on: August 04, 2009, 02:02:18 PM »
THANK-YOU!!!!

Just downloaded the manual from the hondamatic.net site --- will read it tonight and check some adjustments this week. Fortunately I have a partial parts bike and a complete one for parts if needed. Not sure of the years as it looks like the solenoid is different from 76 and the 77-78 models. Like the idea of a smaller sprocket --- if the ones on there were not new I would do that -- maybe i will anyway.

Wayne (wisconsin)