Author Topic: RS34 Tuning and General Information  (Read 15118 times)

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Offline PeWe

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Re: RS34 Tuning and General Information
« Reply #25 on: August 08, 2023, 01:31:50 AM »
Seems to be as my TMR, under side inlet side of throttle.
But these are more visible.

You have to adjust by feel.
1/8 turn make big difference on my Mikuni TMR32.

I seated all lightly. Photo of all with telephone.

Later fine tuned all after final photos when I knew that open 3/4 turn was the best setting. Compared photos and saw that one was 1/32 turn wrong despite my very careful adjustment.

Easy they could differ 1/16. Sometimes even 1/8.

I used a small screwdriver I have cut down the plastic handle on.

I have another short one for main jet.

A 3rd one for pilot jet.
They cannot be long when changing or adjustin with carbs on

Fuel screw and pilot jet screwdrivers trimmed on a bench grinder to fit the screws as good as possible.

From a kit of small screwdrivers with one bigger handle to mount. All in a small box.


My adjusted screwdrivers.
Main jet - black
Fuel screw - yellow
Pilot jet - red
« Last Edit: August 08, 2023, 01:49:21 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

Offline Ellz10

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Re: RS34 Tuning and General Information
« Reply #26 on: August 08, 2023, 08:52:17 AM »
Seems to be as my TMR, under side inlet side of throttle.
But these are more visible.

You have to adjust by feel.
1/8 turn make big difference on my Mikuni TMR32.

I seated all lightly. Photo of all with telephone.

Later fine tuned all after final photos when I knew that open 3/4 turn was the best setting. Compared photos and saw that one was 1/32 turn wrong despite my very careful adjustment.

Easy they could differ 1/16. Sometimes even 1/8.

I used a small screwdriver I have cut down the plastic handle on.

I have another short one for main jet.

A 3rd one for pilot jet.
They cannot be long when changing or adjustin with carbs on

Fuel screw and pilot jet screwdrivers trimmed on a bench grinder to fit the screws as good as possible.

From a kit of small screwdrivers with one bigger handle to mount. All in a small box.


My adjusted screwdrivers.
Main jet - black
Fuel screw - yellow
Pilot jet - red


Perfect, thanks Pete!

Is there a set standard for where they should be placed to start adjustments or no?

Because my air/fuel mixture is WAY off and I don't understand which way to turn the screws or what needs to be adjusted after those screws are turned, ect.

It's all very complicated and I'm trying to understand it - I want and need to understand it.
Thankful for everyone on this forum. Grateful to continue to learn so much.



'77 K7 - http://forums.sohc4.net/index.php/topic,193043.msg2251436/topicseen.html#new

Offline PeWe

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Re: RS34 Tuning and General Information
« Reply #27 on: August 08, 2023, 09:04:51 AM »
See Mikes reply #14
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 Ellz10

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Re: RS34 Tuning and General Information
« Reply #28 on: August 08, 2023, 07:21:25 PM »
See Mikes reply #14

Oh so he was referring to the air/fuel mixture screws when he talked about turning them starting at 1 turn out?

I didn't realize that's what he meant!
Thankful for everyone on this forum. Grateful to continue to learn so much.



'77 K7 - http://forums.sohc4.net/index.php/topic,193043.msg2251436/topicseen.html#new

Offline Ellz10

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Re: RS34 Tuning and General Information
« Reply #29 on: October 05, 2023, 07:54:07 AM »
See Mikes reply #14

Oh so he was referring to the air/fuel mixture screws when he talked about turning them starting at 1 turn out?

I didn't realize that's what he meant!

Just to reiterate, I should turn those screws all the way in til they stop and then turn them out 1 full turn as a starting point?

Should all 4 screws always be turned out the same amount when making adjustments?
Thankful for everyone on this forum. Grateful to continue to learn so much.



'77 K7 - http://forums.sohc4.net/index.php/topic,193043.msg2251436/topicseen.html#new

Offline PeWe

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Re: RS34 Tuning and General Information
« Reply #30 on: October 05, 2023, 09:02:34 AM »
See Mikes reply #14

Oh so he was referring to the air/fuel mixture screws when he talked about turning them starting at 1 turn out?

I didn't realize that's what he meant!

Just to reiterate, I should turn those screws all the way in til they stop and then turn them out 1 full turn as a starting point?

Should all 4 screws always be turned out the same amount when making adjustments?
Yes, all same.
My TMR32's are very sensitive in this matter.
They are located at the bottom pointing downwards.

All softly closed.

I finally took photos on all 4. Phone selfie camera. Blurry when too close but possible to see.

Adjusted to what I had found work. Photos again and saw that one carb was slightly different. Adjusted.

This was the final adjustment when everything ran fine. A kind of carb sync.
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 Ellz10

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Re: RS34 Tuning and General Information
« Reply #31 on: October 06, 2023, 06:06:23 PM »
When turning these screws to make adjustments, which way equals what?

If I start them all out at one full turn, what would turning them out further do - make it run more rich or more lean?
Thankful for everyone on this forum. Grateful to continue to learn so much.



'77 K7 - http://forums.sohc4.net/index.php/topic,193043.msg2251436/topicseen.html#new

Offline PeWe

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Re: RS34 Tuning and General Information
« Reply #32 on: October 06, 2023, 09:12:47 PM »
Fuel screws, more fuel when out.
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 CB750R

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Re: RS34 Tuning and General Information
« Reply #33 on: July 06, 2024, 11:52:55 PM »
I’m still working on my RS34 but wanted to share that I found a flexible extended “rack” or main idle adjustment screw on eBay. I find having the rack idle screw extremely useful while still sorting out your jetting