Author Topic: Hydraulic clutch conversion for the mono shock dragbike. Will it work??  (Read 3684 times)

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Offline dragracer

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I've decided to try something a little different fir the clutch set up on the mono shock dragbike. I saw something on a SOHC group post on Facebook regarding the use of a universal type hydraulic clutch kit on a 750. While the poster wasn't detailed on his installation there were a few pictures that graphically showed the basics.  Mind you i have not searched our forum yet to see if   someone here has already done the conversion. I searched Ebay and Amazon for a complete kit and found one for less than  $50. It included the handlebar mounted clutch master cylinder, a slave unit with fittings and a plastic covered braided steel hydraulic line. There was also a matching brake master cylinder.  Both had adjustable positions for the levers along with appropriate switches. I grabbed a stock clutch cover to see how the slave cylinder could be positioned to pull the stock Honda lever on the cover.  The slave unit is threaded on the end with the pull rod which is also threaded for a ball type clevis. The clevis slipped right into place of the cable end perfected but the thread diameter of the slave unit was small than the opening on the clutch cover housing. I decided to try putting a stock adjuster from an old cable onto the slave unit and i was pleasantly surprised that the thread pitch was the same, allowing the identical adjustments we'd utilize with a stock cable. Wow!!! At the moment i have not put the cover on an engine with the full stock clutch and springs inside. I  plan to mock everything up when i get time and add fluid to the system to do a bench test. My main concern is will the little slave cylinder have sufficient pulling capacity to move the stock lever with heavy duty clutch springs. To be on the safe side, i researched Amazon for a slave cylinder that has a larger piston. This one is 14mm. I bought a larger one for $25 that has a 19mm piston. I'll swap the bigger one as I'm setting everything up and hope for the best. My main purpose here is to reduce lever effort and eliminate moving parts. My brother is having some issues with the current lever so I'm trying to make itveasuer for him without compromising the use of the heavier clutch springs.  I'll let you know how it goes

Offline scottly

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #1 on: September 19, 2024, 10:18:13 PM »
There are posts here regarding hydraulic clutch conversions, Frank. ;)
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Offline scottly

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Don't fix it if it ain't broke!
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Offline dragracer

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #3 on: September 19, 2024, 10:24:31 PM »
There are posts here regarding hydraulic clutch conversions, Frank. ;)

I figured it had already been done at some point. I'll probably delete my post then since likely won't be contributing anything to help the group. I should have searched first. 😅🤣

Offline dusterdude

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #4 on: September 19, 2024, 11:36:35 PM »
Keep posting frank,we are interested

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Offline newday777

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #5 on: September 20, 2024, 04:01:21 AM »
There are posts here regarding hydraulic clutch conversions, Frank. ;)

I figured it had already been done at some point. I'll probably delete my post then since likely won't be contributing anything to help the group. I should have searched first. 😅🤣
Oh don't delete it! It can be helpful to anyone thinking of doing it to their bike, besides you are using a pull slave without major modifications to the original clutch cover working design as apposed to the push slave of the link. I'm interested in this style to be able to make clutch adjustments as necessary.
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline RAFster122s

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #6 on: September 20, 2024, 09:51:54 AM »
Hasn't Godfrey's Garage done one or two hydraulic clutches, seem to recall photos... Maybe reach out to Mark...if he has experience with them he could be of help guiding you if you encounter an issue he has overcame with one...
David- back in the desert SW!

Offline Leino

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #7 on: September 20, 2024, 01:51:52 PM »
TLR has a hydraulic clutch and when it comes to launching a bike it's absolutely useless compared to a cable operated clutch. If hydraulic clutch was better I think guys at Speedway GP would have one as they are the second hardest launching motorcycle racers I can think of. No feedback at all at the lever.

Offline Leino

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #8 on: September 20, 2024, 02:07:01 PM »
My opinion, yours may be different  ;D

Offline MRieck

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #9 on: September 20, 2024, 04:33:39 PM »
My opinion, yours may be different  ;D
Haven't you gone the 1/4 mile a couple of times? I can't remember. ;)
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Offline dragracer

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #10 on: September 20, 2024, 09:53:38 PM »
90% of the weekend warriors that drag race modern bikes are factory equipped with hydraulic clutches. They even use them with mallet magnet releases off  a button and a 2 step. Many are set up with Gen 2 MTC multistage clutches. I'm not certain this style slave systems will release quick enough but i want to give it a shot since it requires no machining thus far and it was cheap. Nothing ventured, nothing gained. I'll report back as this progresses. Its not a must do project at the moment so I'll pick at it when nothing else is important. I'm hopefully it will work as intended.

Offline Tracksnblades1

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #11 on: September 21, 2024, 08:28:13 AM »
90% of the weekend warriors that drag race modern bikes are factory equipped with hydraulic clutches. They even use them with mallet magnet releases off  a button and a 2 step. Many are set up with Gen 2 MTC multistage clutches. I'm not certain this style slave systems will release quick enough but i want to give it a shot since it requires no machining thus far and it was cheap. Nothing ventured, nothing gained. I'll report back as this progresses. Its not a must do project at the moment so I'll pick at it when nothing else is important. I'm hopefully it will work as intended.

I’m betting your the guy that’ll definitely get her (hydraulic clutch) dialed in…
Age Quod Agis

Offline Leino

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #12 on: September 21, 2024, 08:49:09 AM »
90% of the weekend warriors that drag race modern bikes are factory equipped with hydraulic clutches. They even use them with mallet magnet releases off  a button and a 2 step. Many are set up with Gen 2 MTC multistage clutches. I'm not certain this style slave systems will release quick enough but i want to give it a shot since it requires no machining thus far and it was cheap. Nothing ventured, nothing gained. I'll report back as this progresses. Its not a must do project at the moment so I'll pick at it when nothing else is important. I'm hopefully it will work as intended.
You are absolutely right, I'm oldskool  ;D
To me a modern bike is not early 80's  ;D

Offline Leino

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #13 on: September 21, 2024, 08:50:04 AM »
My opinion, yours may be different  ;D
Haven't you gone the 1/4 mile a couple of times? I can't remember. ;)
I tried it a couple of times without much success but yes, you have a good memory  ;D

Offline dragracer

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #14 on: October 02, 2024, 12:44:59 AM »
My opinion, yours may be different  ;D
Haven't you gone the 1/4 mile a couple of times? I can't remember. ;)
I tried it a couple of times without much success but yes, you have a good memory  ;D

I've been trying it for years and I'm still not worth a damn at the sport!!!

Offline MRieck

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #15 on: October 02, 2024, 03:09:57 PM »
My opinion, yours may be different  ;D
Haven't you gone the 1/4 mile a couple of times? I can't remember. ;)
I tried it a couple of times without much success but yes, you have a good memory  ;D

I've been trying it for years and I'm still not worth a damn at the sport!!!
When I look at somebody drag racing a bike I look to see how comfortable ( which is a product of experience) on that bike. Frank.....you look like you've been riding that F since you were 10 years old. You look loose but ready to pounce. I used to see that in Stetson.....you could tell he has thrown a leg over his bike a million times. ;) ;)
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Offline spotty

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #16 on: October 02, 2024, 07:27:55 PM »
ive got all the same parts to do mine, but i'm using a vmax m/c. i shall be following along to see how it goes. good luck
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #17 on: October 03, 2024, 07:51:45 AM »
My opinion, yours may be different  ;D
Haven't you gone the 1/4 mile a couple of times? I can't remember. ;)
I tried it a couple of times without much success but yes, you have a good memory  ;D

Frank is just a little modest
I've been trying it for years and I'm still not worth a damn at the sport!!!
When I look at somebody drag racing a bike I look to see how comfortable ( which is a product of experience) on that bike. Frank.....you look like you've been riding that F since you were 10 years old. You look loose but ready to pounce. I used to see that in Stetson.....you could tell he has thrown a leg over his bike a million times. ;) ;)
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Online PeWe

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #18 on: October 03, 2024, 11:45:12 PM »



To me a modern bike is not early 80's  ;D
Ha, ha, ha.... ;) ;)
I am still in the 80's as modern bikes.
When I saw the beautiful CB1100F -83 with round headlight and no fairing, a newer bike, almost modern. ;) ;)

Maybe the real "modern" bikes have fuel injection and well working brakes, ABS. No wires at all, "throttle by wire" means no wire... Same with clutch.
Next step, ride modes.....

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 MisterKnife

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #19 on: October 04, 2024, 08:14:52 AM »
I'm using a hayabusa master clutch and a slave cylinder for my CB550, works like a charm!

Offline MRieck

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #20 on: October 04, 2024, 06:13:48 PM »
I'd love to have a hydraulic clutch on my bike....I need a lot of spring for my engine. It's getting hard to work the older I get.
Owner of the "Million Dollar CB"

Offline dragracer

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #21 on: October 05, 2024, 11:11:58 PM »
The one potential draw back for me as a dragracer is the release speed, and full engagement of the clutch. I'm still trying to utilize the stock cover with components as factory designed. Basically I'm only  eliminating the stock mechanical clutch lever and cable. Using the pull type slave cylinder in this kit,  there could be a mechanical disadvantage versus a slave cylinder pushing directly against the lifter plate. I'm also trying to make this as simple as possible without having one off components by utilization of an easily attainable kit from either Amazon or ebay. I may get lucky and it works out perfectly for me and other home mechanics interested in an easier clutch lever pull when using medium to heavy duty springs for larger than stock engines.

Offline dragracer

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #22 on: October 05, 2024, 11:22:41 PM »
I think i mentioned this in my opening post, but the kit has adjustable levers. This can become an important factor for me when racing because i can taylor my lever release position with the actual initial clutch engagement/movement of the  bike to help with rider reaction times.  There's no advantage to having that lever against the bars if the release point is at the end of travel.

Online PeWe

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #23 on: October 06, 2024, 12:59:57 AM »
I'd love to have a hydraulic clutch on my bike....I need a lot of spring for my engine. It's getting hard to work the older I get.
My K6 has the harder Barnett springs. Middle number -66-. Slips with -56-.
Dog leg style lever helped. The finger torturing clutch. Teflon spray in cable.

Much nicer feel for brake too. Nicer shape/profile.
My K2 got also a set. Vintagecb750 has.
Here stock clutch lever under to show  the difference.
« Last Edit: October 06, 2024, 01:04:25 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 Don R

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Re: Hydraulic clutch conversion for the mono shock dragbike. Will it work??
« Reply #24 on: October 06, 2024, 06:17:25 PM »
 I'm thinking I accidentally put valve springs in the late clutch in my Rat Race bike. L0L! Dang they're hard on an old worn out hand.
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