Topic: New clutch, can't get it adjusted. 74 550k.

[Dimitri13]

So I'm finally assembling the bike after about 7 years being apart. I have the clutch basket assembled, pivot arm installed, clutch actuator installed. I put the cable on and it seems to be nearly an inch away from being able to grab.

I disassembled it twice, matched with the niche and service manual. I even matched my new cable to my old one in case they were different and they're not.

I can almost get the notch on the actuator arm matched up to the mark on the cover by backing the screw all the way out, but it's still not lined up.

I have a barnett heavy duty clutch +1 plate kit going into the original basket.

Attached are pictures of everything in the order they're assembled. I do have the thrusts washer there, it's on the bike side.

[bryanj]

If the clutch is not a standard Honda one you will not get the marks to line up

[Dimitri13]

That makes sense. But I still can't get the clutch cable to grab. The entire travel of the clutch lever is loose.

[Dimitri13]

Got the clutch kit from Dynoman Performance, checked the part numbers on the box and the application and they're correct. 74 550 appears to have all the same size fiber plates, unlike the later clutches that use one big plate.

Following the manual's clutch adjustment procedure.
Undo the lock nut, back out the adjuster all the way til it stops then go a tiny turn in so it's not bottomed out. At that adjustment the lifter arm is at the lowest adjustment and any adjustment the other way makes it worse.

That's where I'm stuck and what I mean by the cable doesn't grab. The adjustment at the lever won't make any noticeable difference.

I triple checked the assembly. Thrust washer, clutch basket, collar, pressure plate, alternation fiber and steel plates so that fiber plates are on the outsides of the stack, outer clutch basket hub thingy, thin spacer, circlip, springs, lifter plate, then lifter rod.

Everything seems to be there and not broken. I can roll the bike an inch in gear and the clutch pack will spin. But when I get the cover on I can't get the clutch cable to catch (compared it to my old clutch cable that worked and it matches).

[dave500]

the stack is too thick,also how have you assemble the cable onto the bracket it should be done like this.

[steeldoncb550]

Remove a plate. I thought the +1 kits were only to cover all year bikes.

[Dimitri13]

After removing a set of plates it just looks too thin to me. I'll try it anyway because I'm all out of ideas.

I was under the impression that the +1 kit was to somehow make it more heavy duty. A greater quantity of thinner plates for more surface area or something?  Unsure.

[bryanj]

Make sure you havent adjusted the screw too far and let the lever "pop" to the wrong side of the cam

[Dimitri13]

Removing a plate let me get the correct adjustment,  but it maybe feels like it's too loose now? I can see the clutch pack through the oil cap hole and it never fully closes. I don't know what it's supposed to look like but it doesn't look or feel right. I can definitely get into gear but the rear tire moves too easily.

[dave500]

so you mean the clutch slips?

[flatlander]

you need to get the stack height right, which can be tricky with aftermarket parts that are made to some generic spec. if the full pack that you have is too tall and removing a plat makes it too low, then you can look for another, thinner plate and add it.

i made an 8-plate clutch from mixing stock parts of different models. this thread might help: http://forums.sohc4.net/index.php/topic,145565.0.html

[Dimitri13]

Yes, sorry, in my frustration I couldn't even remember what clutch slippage was. But yes, the clutch is slipping. With the 8-plate clutch, it was perpetually engaged. With the 7-plate clutch, it never fully engages. When in gear I can feel a bit of resistance when spinning the tire but the clutch is slipping badly.

I look at that thread and my solution might be replace some of the kit's steel plates with some of my old stock steel plates.

My question is why is this clutch giving me so many issues? I don't think every 74 550k owner that bought this kit had this issue?

[flatlander]

the clutch design went through several iterations, and changed not only between the 550 model types but per serial number range. you can see this in the parts list. as a result one aftermarket clutch pack does not fit all 550s. aftermarket manufacturers mostly ignore this, i guess it's because too complex and costly for them to track and offer separate parts per engine serial number range.

meaning, the easiest thing is to get the correct OEM parts for your engine serial number or you might need to mix and match parts until you get the pack height that you need.

[seanbarney41]

Why do you think you need new clutch?  Even drag racers have found the stock parts most satisfactory.

[flatlander]

i agree, the stock parts are the way to go. especially those heavy duty aftermarket springs don't do anything except make it harder to operate.
but now he has that complete pack - would be cheaper to adjust it with some extra parts than ditch it completely.

[steeldoncb550]

I’m still going to say you need to use 7 plates. The +1 kits are designed to accommodate all years. I did a full Barnett clutch install on mine. Discs, plates and springs. My guess is either you are yet to soak your plates in oil and they are dry which is why they’re slipping or you have too many steel plates. Should only be 5 steel plates.

[Dimitri13]

Since I already have this kit and don't have enough time to wait for a new kit (plus the cost) I'm going to try to mix and match to get the correct height.

My old clutch was either worn out as I was getting a bit of slippage. Plus an engine failure scattered metal confetti everywhere.

I soaked my plates in oil for about an hour while I was assembling other things. When you say that I should have 7 plates and 5 plates, you mean 7 fiber and 5 steel? How does that work? They're all the same style and that would mean two fiber plates are next to each other.

I am a bit confused about the diagram though:

[steeldoncb550]

Since I already have this kit and don't have enough time to wait for a new kit (plus the cost) I'm going to try to mix and match to get the correct height.

My old clutch was either worn out as I was getting a bit of slippage. Plus an engine failure scattered metal confetti everywhere.

I soaked my plates in oil for about an hour while I was assembling other things. When you say that I should have 7 plates and 5 plates, you mean 7 fiber and 5 steel? How does that work? They're all the same style and that would mean two fiber plates are next to each other.

I am a bit confused about the diagram though:

That diagram is confusing lol. Sandwich it like this: F/S/F/S/F/S/F/S/F/S/F/S/F
F for fibre and S for steel. I missed quoted you on the steel plates.

[flatlander]

also you may need to soak the fibers longer than 1hr. just leave them over night.

[dave500]

you can put steel to steel if it makes the pack correct,they dont slip against each other.

[Dimitri13]

Interesting suggestions. I'll disassemble the pack tonight, put it back to soak and work on other stuff. Tomorrow I'll rebuild the pack and see what works. Is there anything I should be looking for?

When I assembled the pack with -1 fiber and -1 steel I could spin the clutch pack by hand when the lifter plate was fully tightened down. When I had the 8 and 7 plates in, as soon as I started tightening the lifter plate down, I basically couldn't spin the clutch pack at all.

[flatlander]

yeah so you need something in-between. take off 1 fibre and add 1 of the steels next to another one (fssf), then give it a try.

[Dimitri13]

Thanks for all the advice y'all. I didn't get out to the garage tonight, it might have to wait til Friday

On paper it seems like having 7 fibers and 7 steels (two next to each other) is the solution, so hopefully it's as simple as that.

In the meantime I also emailed the shop (not just a big parts vendor but an actual performance shop) I got the kit from to see if they had any advice as well.

[HondaMan]

I've posted about this many times....

The vendors are NOT helping the 500/550 owners out, here.

The 550 plates are supposed to be 0.121" thick. The vendors are selling other thicknesses, some thinner
(0.107 from superbike clutches) or thicker (Barnett) with no regard for the incorrect stack height you must have. The lifter in the 550 can only tolerate +/- 0.5 thickness of 1 plate (i.e., 0.0605") of total mis-height sizes, any more than that will either make the whole stack taller than the lifter can even touch, or so short that the lifter cannot reach under the lip of the lift finger.

So...to get the height you need, start with this: there are 7 plates of 0.121" thick cork plates in the OEM clutch, with the steel plates added to this height. If you use other plates' thicknesses, you must either make the height come out right by using different counts of the cork plates, or by mixing thicknesses of cork plates. For example, I have use 2 of the 0.107" (superbike) and 5 of the 0.138" (CB750 size) cork plates with the stock steel plates, which yields a stack height of almost identical thickness to the OEM 0.121" plates. setup.

The lifter has only 3mm of "reach" total adjustment, so you don't get to alter the clutch much. That's OK, because the stock clutch can handle more than 70 HP, which your 550 will never attain.

[Dimitri13]

I've posted about this many times....

The vendors are NOT helping the 500/550 owners out, here.

The 550 plates are supposed to be 0.121" thick. The vendors are selling other thicknesses, some thinner
(0.107 from superbike clutches) or thicker (Barnett) with no regard for the incorrect stack height you must have. The lifter in the 550 can only tolerate +/- 0.5 thickness of 1 plate (i.e., 0.0605") of total mis-height sizes, any more than that will either make the whole stack taller than the lifter can even touch, or so short that the lifter cannot reach under the lip of the lift finger.

So...to get the height you need, start with this: there are 7 plates of 0.121" thick cork plates in the OEM clutch, with the steel plates added to this height. If you use other plates' thicknesses, you must either make the height come out right by using different counts of the cork plates, or by mixing thicknesses of cork plates. For example, I have use 2 of the 0.107" (superbike) and 5 of the 0.138" (CB750 size) cork plates with the stock steel plates, which yields a stack height of almost identical thickness to the OEM 0.121" plates. setup.

The lifter has only 3mm of "reach" total adjustment, so you don't get to alter the clutch much. That's OK, because the stock clutch can handle more than 70 HP, which your 550 will never attain.

Thanks for this. I did see some of your other posts while googling, but couldn't figure out The numbers helped me understand that such a small difference can make it inoperable.

I miced the steel and fiber plates in my kit and found they were 2.7mm and 1.4mm respectively. That comes out to 31.4mm, which is 1mm (.0393") taller than the 30.4mm I was told the stack was supposed to be. That doesn't seem to be so much out of spec from the .0605" you mentioned.

Maybe 30.4mm isn't the correct stack height either? This is all according to just adding the thicknesses together so I don't know if there's any squish room or anything to take into account.

[HondaMan]

Here's another 'metric' that you can use: the top edge of the top pressure plate of the clutch should be even height with the ends of the clutch basket fingers. The lifter can reach it if it is within +/-0.5mm from dead-equal height, leaving you some adjustment afterward.

his all came about because Honda was sensitive to the magazines of the 1970s complaining about the shifting clutch engagement point of the clutch lever on the CB500-4. the long clutch rod that went thru that engine was steel, while the cases were aluminum alloy: the cases spread about 1mm in width as the engine heats up, while the clutch rod only extended 0.2mm (at 200 degrees F). The result was that the lever had to be adjusted to 0 clearance when cold to get 0.5" (6mm) slack at full temperature. In the CB550, the clutch lifter was grafted into the existing cases and the top pressure plate thickened a little bit, and the disengagement direction was changed to push from the right side instead of from the left, so the total change-for-heat difference at the lever became less than 2mm after warmup. But...this also reduced the available lift distance to less than 5mm total travel because of the shape of the little lifter cam and the lack of space to make it bigger without redesigning major parts of the engine. While it was a clever fix at the time, it does leave the stack height of the clutch as a critical dimension.

All this info is lost to modern vendors, though, as they just sell stuff without doing research on whether it will actually WORK in the bikes. This is much, much different from the Honda community of the last century! We're really fortunate to have this SOHC4 forum so we can get this info out to those who love these bikes as much as we who rode them since 1969.

[Dimitri13]

Lots of great information there. I'm about to head down to the garage to get this assembled. Will report back with results.

[Dimitri13]

I have 7 fibers and 7 steels (steel to steel on one set).

I have proper engagement and disengagement but when in gear and the clutch disengaged it drags a bit. Not enough to catch the engine but definitely enough that the tire spins less than a quarter rotation when spun by hand.

I can't remember if that's how it is because it's been many years since I've had a complete bike.

[steeldoncb550]

I have 7 fibers and 7 steels (steel to steel on one set).

I have proper engagement and disengagement but when in gear and the clutch disengaged it drags a bit. Not enough to catch the engine but definitely enough that the tire spins less than a quarter rotation when spun by hand.

I can't remember if that's how it is because it's been many years since I've had a complete bike.

Still too thick. Try what I said from the beginning fibres on outsides and no steel to steel.

[Dimitri13]

I have 7 fibers and 7 steels (steel to steel on one set).

I have proper engagement and disengagement but when in gear and the clutch disengaged it drags a bit. Not enough to catch the engine but definitely enough that the tire spins less than a quarter rotation when spun by hand.

I can't remember if that's how it is because it's been many years since I've had a complete bike.

Still too thick. Try what I said from the beginning fibres on outsides and no steel to steel.

7 fiber 6 steel right? I did try that one but it was too loose.

[steeldoncb550]

I have 7 fibers and 7 steels (steel to steel on one set).

I have proper engagement and disengagement but when in gear and the clutch disengaged it drags a bit. Not enough to catch the engine but definitely enough that the tire spins less than a quarter rotation when spun by hand.

I can't remember if that's how it is because it's been many years since I've had a complete bike.

Still too thick. Try what I said from the beginning fibres on outsides and no steel to steel.

7 fiber 6 steel right? I did try that one but it was too loose.

Watch this and skip to 10:20 mark.

[Dimitri13]

Yeah my clutch pack is very nearly that height but with 7 of each plate. 8 fiber 7 steel is way too thick, 7 fiber 6 steel is a bit too thin.

[dave500]

too bad hes got the cable at the bracket wrong though!the sleeve nut goes from above into the holder and its locked from above with the nut