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Slipping clutch...Replace as a amateur or pay to have it done?

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snakemantim

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So I have a 1978 cb750k and I notice the clutch doesn't fully engage ( is what it feels like), and when I shift it, I have to almost kick it into gear because if I just lift normally it just grinds. This seems like a clutch issue to me and I saw that the friction plate kits are not crazy expensive so I had to wonder if it was worth having a go at it myself. I watched a couple videos and it looks straight forward but I did notice a couple things.
1. No one lists where they get their parts.
2. No one mentions whether you need to replace the springs as well as the disks.
3. Do you drain the oil when you replace it? One guy shows draining a fluid but he didn't say what it was or anything about it he just replaces the plates closes it up and says he is done.

I don't know a whole lot about how bikes run and I am wanting to learn, I understand the basics of how the transmission and clutch works I just am unsure about the details.

I know you need to replace the gasket but I don't know where to get it.

Basically I want to know if this is something I can figure out with guidance or if I should take it back to the mechanic and spend another who knows how many dollars having it done.

Thanks in advance
 
That's not slipping at all if described correctly, it's not fully DISengaging.

'...when I shift it, I have to almost kick it into gear because if I just lift normally it just grinds.'

Adjust it a bit more, that should come right out. You have to kick it in gear (how you bend shift forks to have to tear engine apart) because the clutch has not fully released. Slipping clutches (not fully engaging) are the opposite, they never grab fully anymore. A new clutch will only make that worse, you adjust it to get rid of that.

A slipping clutch is one that lets the engine rpm come up in gear while bike goes no faster with the clutch lever all the way out.

The clutch must fully release to break the engine to transmission connection, that is what allows the gears to switch from one to another. When the connection is not broken then the gears are loaded in such a way as to not be able to come apart to make the shift.

Oops, I forgot.................I'M the -sshole.

I didn't need you to tell me what I already know. But like with the electrics, I know how the clutches work too.
 
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The 750's need a firm push and pull on the shifter or they will "grind" if you push or pull to lightly. The clutches do have a little bit of drag to them. There is actually a mod you do to the inner clutch basket to help control the oil going to the clutch. But you still could have an adjustment issue. As far as parts go, APE, Dynoman have more of performance type clutches. Cycle X also has high performance clutches but have a good streetable clutch as well. CB750supply.com has a cheap clutch kit...not sure of quality as I have never used it, they also have cheap gaskets which will work fine if you just use a little high tac or hondabond. Stock springs are usually fine in stock motors. You dont need to drain oil to change the clutch, if it that high you have issues with the check valve in the oil pump.
 
On a side note, like I have had to say many times before and seem to keep having to say...we are here to help one another. The internet makes it hard to express feelings and how you intended to express your words. This causes people to take things said the wrong way many times. We need to not take things so personal and we need to try hard to just write what will help the people posting rather then trying to belittle them...whether you mean to or not. Just answer the question and move on. I try to keep this board a good source of information and not try to let it get to a point where people get mad and leave because someone says something that pisses someone else off. I know not always avoidable but if everyone leaves there wont be a forum to help each other out will there? So I AGAIN ask please just answer the questions with helpfull and pertinent information, this is supposed to be a fun hobby and we have to recognize that not everyone is mechanically inclined and we arent born with this knowledge, it is learn from others it is all a learning experience so lets justs help each other out. End of rant...until the next time.
 
You know I just wanted the advice, like "oh you need to adjust it! its not slipping its this other thing! Cheers" Not "I know stuff so stfu peon!"
 
I appreciate the info and your "rant" is very applicable. amc does not seem to understand that this forum is not here just for him to feel high and mighty about all his knowledge.
 
So to clarify, since you would rather lecture than give a straight answer. I need to loosen the clutch cable? Since it would not be fully DISengaging even when the lever is all the way out correct?
 
Hi, Again! Just reading your clutch problems. 1st I don't have a SOHC CB. Mine is DOHC so I'm not on intimate terms with the ins &
outs of your bike. However clutches all do the same job, to disconnect the engine from the driving wheels be it car or bike. This takes the load off the gears thus enabling you to shift from one to another.
On our bikes the clutch is cable operated, so that cable needs to be correctly adjusted in order for the clutch to work correctly.
Now, if the clutch lever has too much free play, i.e. There is no or little resistance to pulling the leaver back, that lever movement is lost and the clutch will not disengage fully or not at all thus leaving the load on the gears, making the gears difficult or impossible to shift.
Now, if there is not enough free play, the clutch will not fully re-engage leading to clutch slip, the give away is the engine will rev up but there will be no increase in speed. In general there should be about 1/4 inch free play at the END of the lever then you should be able to feel the weight of the clutch springs being compressed and the clutch should fully disengage.
If the cable is correctly adjusted then if there is clutch slip then you will need to look into the clutch. The plates may be worn and or the springs are tired and have become too weak to hold engagement. Either way new plates and springs are called for. New springs and plates can also cause a tired and worn cable to snap under the new load.
If the cable is correctly adjusted and the gears still clash then again look to the springs and plates. Hope this helps. By the way, have you got a Honda workshop manual for you bike, if not, best you get one.
 
Hi, Again! Just reading your clutch problems. 1st I don't have a SOHC CB. Mine is DOHC so I'm not on intimate terms with the ins &
outs of your bike. However clutches all do the same job, to disconnect the engine from the driving wheels be it car or bike. This takes the load off the gears thus enabling you to shift from one to another.
On our bikes the clutch is cable operated, so that cable needs to be correctly adjusted in order for the clutch to work correctly.
Now, if the clutch lever has too much free play, i.e. There is no or little resistance to pulling the leaver back, that lever movement is lost and the clutch will not disengage fully or not at all thus leaving the load on the gears, making the gears difficult or impossible to shift.
Now, if there is not enough free play, the clutch will not fully re-engage leading to clutch slip, the give away is the engine will rev up but there will be no increase in speed. In general there should be about 1/4 inch free play at the END of the lever then you should be able to feel the weight of the clutch springs being compressed and the clutch should fully disengage.
If the cable is correctly adjusted then if there is clutch slip then you will need to look into the clutch. The plates may be worn and or the springs are tired and have become too weak to hold engagement. Either way new plates and springs are called for. New springs and plates can also cause a tired and worn cable to snap under the new load.
If the cable is correctly adjusted and the gears still clash then again look to the springs and plates. Hope this helps. By the way, have you got a Honda workshop manual for you bike, if not, best you get one.


Thanks for the info, No I do not have the manual. I will look on ebay for one asap.
 
If you loosen the cable you will be making the problem worse. Not fully disengaging means the clutch plates arent releasing all the way when the clutch lever is pulled in. If you loosen the cable you wont be disengaging the clutch plates and the clutch will drag. Another thing that causes clutch drag is grooves in the inner and outer clutch drum they wear in all of them with enough miles. The grooves dont let the disks to move far enough and cause the to drag. Weak clutch springs wont cause clutch drag only slippage. You should have just a little bit of free play in clutch lever.
 
I will leave this poster alone as his problem is not solvable, the REAL problem anyway. You guys can enjoy your little dance around that, I don't dance.
 
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MY rant. I do not feel 'obliged' to help anyone who goes out of the way to call me names and why I posted what I did. I like to help people but I have no use for those that quite literally want to be coddled like a baby. That's beyond simple helping of people and others can do it if they want, I choose not to.

I tried to stop OP from wasting money on a new clutch not needed, where is the thanks for that? He made sure he called me a name though, how childlike. And I also pointed out the error in clutch adjusting. In the past this same person has shown us a bundle of loose wires and asked what one only did and no indication of the 50 wires there which one it was, he then got mad when I pointed that out.

Very helpful in trying to save me money, however you did not actually propose a solution to the problem you basically just said, no its not that its this other thing. Useful but not actually helpful because now I have to ask, How do you adjust it to be fully disengaged? So you weren't actually helpful.
 
MY rant. I do not feel 'obliged' to help anyone who goes out of the way to call me names and why I posted what I did. I like to help people but I have no use for those that quite literally want to be coddled like a baby. That's beyond simple helping of people and others can do it if they want, I choose not to.

I tried to stop OP from wasting money on a new clutch not needed, where is the thanks for that? He made sure he called me a name though, how childlike. And I also pointed out the error in needing clutch adjusting. In the past this same person has shown us a bundle of loose wires and asked what one only did and no indication of the 50 wires there which one it was, he then got mad when I pointed that out. Got mad when he found out the new battery had to be charged, got mad when told the old one needed to be checked, and simply bought another and maybe again for nothing. Claimed he knew 'all about electricity', or the same bragging that he accuses me of except he obviously DOESN'T know. Reading his posts is an exercise in realizing how bad people can do things like leaving bike open to the rain and then things quit working. The biggest common problem there is the bike OWNER. Yes, the bike has THAT problem and playing the game like suggested in rant above does NOTHING but waste peoples' time, because the owners NEVER fix themselves. (Actually, a very few do.)

I fix countless computer controlled cars over the web and this owner issue is by far the biggest problem to get over to fix the cars. They generally have faulty ideas of how the cars work or even how basic physics work to shoot themselves in the face over and over, then they get mad at others next. Try to help them to think that one little thing they think is wrong and their brains simply explode and there is no fix for that, only more bi-ching. I bring a lot of that on myself but it crystallizes who the losers are quicker than spit and why I do it. I don't waste my time with losers. Well, maybe sometimes hoping they will clue in. My mistake there in this case.

I trained people who didn't know anything on a lot of things and to have them commonly go on to do much better, but beyond a certain point it becomes obvious which ones will make it and which are lost to the cause and you are wasting time with those as they will have every excuse for failing over and over. Getting mad at you is what they do when they cannot think of anything else, the box of tricks is sadly empty. You certainly don't expect them to look hard at themselves, nope, they choose to stay stupid forever, it's easier to bug other people for their daily problems than it is to look at oneself in the mirror.

I still like to help people but that will not happen under duress at all. The rest of you can pansy out if you want to help just with the 'problem' but when the problem is the owner you have no recourse to curing problems do you? Work in repair for awhile, you WILL change your viewpoint on that or you will be bankrupt.



Dude...I did not ask for your condescension. I asked a simple question. I want to learn about how these bikes work and the best way I know to learn is to ask those with more experience. However, my lack of experience does not mean I am an idiot. There are three major points in your narcissistic dialog I will address not because your idiocy actually warrants a response but because I enjoy putting stuck up old men back into their place as slightly more experienced yet still normal people.

1. Bringing up another post here is a waste of time and confusing to people who are ACTUALLY trying to help me understand and solve my problem. I am trying to cultivate the tradition of classic bike upkeep and enjoyment into my life because it appeals to me and the community is by and large accepting and welcoming, everyone accept you that is.

2. You are not God, your word is not law and you are not always right. No one is infallible. You were wrong about the wiring and that irks you. You may be accustomed because of your age and experience to having people defer to you. Although it is far more likely that people simply submit to you to prevent your immature outbursts about how amazing you are and how they are all idiots for needing help. If you think that a post is not deserving of your input or if you think that the OP will not appreciate or heed what you have to say, then don't post on that thread. You are not required to do so. I found dirtdigger's reply to be more helpful than yours because instead of insulting me and my progress towards honda 750 proficiency he answered my question with a short explanation to help me understand.

3. My experience with electricity does affect my ability to work on my bike. I can calculate how the current through the starter solenoid produces induction in the wire 3 feet away because I have taken multiple physics classes including Quantum Physics and Thermodynamics. However while the laws and properties that govern electricity are universal, the practical application of the different parts, their names, and placement, the correct values for input, output, voltage changes and current outputs are not. I have built my own electric bicycle from parts and wired the whole thing with little difficulty because I knew the names and uses of all the parts involved. It took time and research but I figured it out. But a large amount of my knowledge on how to do that came from others who had done it first. This is actually how all knowledge of any kind is acquired and distributed. Someone smarter than you or I figured it out first and then shared it with others who shared it with us. (Its called your academic pedigree look it up). Doing something for a long time does not make you an expert and being a dick about it does not make you more right. You can quote the amount of work you have done or the number of people you raised from ignorance but in reality the measure of your accomplishment in a field or expertise is how well you can communicate that knowledge to someone who knows less than you and how well you can perform the work yourself. I see you are still working on the first of those two and can only imagine how you do on the second.

You aren't being helpful so please don't answer my posts in the future unless you can answer the actual question being asked without insulting my intelligence or going on a tangent.
 
You realize of course that I removed that post (#11, look at it now) after self-consideration to try to stay in the spirit of post #4 and dirtdigger being right, yet you willfully brought it back JUST to start trouble. That tells me gallons about the quality of person you are, you are not happy unless scorching all earth around you and stupidly even under your own feet at times.

I already told you I will not be responding further to your posts, you cannot handle anything approaching reality. But again you are not happy unless you can backbite, you've done it twice now. Now you are actually throwing a fit because somebody won't lead you around like a child adjusting the most simple of things, a cable.

You talk like an adult (part of the time anyway) but you certainly don't act like one.
 
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I am going to close this thread as nothing useful is no longer coming from it. If at some point a useful discussion can come about I will reopen. I will close any threads that lead down this path. This has no place on this forum.
 
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