Topic: 500/550 clutch tips.

[HondaMan]

First word: GREASE! The clutch lifters on these bikes wear more because there is much more shifting going on. Grease those lifters!

We tried all kinds of clutch mods. The stock clutch would wear because of the slanted cork block faces, which were designed to let the oiled plates squish out the oil slowly and ease the engagement (part of the "smooth 4 effort" of the 500). Heavy-handed throttles then caused plate heating and warpage, making the faces engage less, then they wore quickly.

Barnett jumped in with their superior friction plates, but they were thicker, so their sets had 1 less plate pair than the Honda set. Result: same grip, less life. Even worse: the Barnett cork bits wear the oil pumps, causing low oil pressure after a while.

Solution: today, the plates are available with square-cut cork faces. Find these and use them. And, replace the steel ones, too. They're warped if you have 10,000 miles on them, believe it. Also, DON'T run Valvoline or Havoline oil. These excellent oils overlube the plates and make them slip. Instead, use Castrol (best) or Torco (next best) oils. Castrol and Honda worked together in the 1970s to get the right blend: trust 'em.

If you're drag-racing: get the Honda slanted-cork plates and put them in backwards. Put the steel ones in backwards, too. They'll grab like a spline clutch and break that rear wheel free at the green light!

[Benjamin]

Hello HondaMan,
I'm a newbee -- tryin' to soak up all I can. You seem to know a lot about the 500 clutch -- I have a real clunky one. I'm wondering a couple things, maybe you can clue me in to a couple of basics:
1) Can I swap out the plates for any other size cycle -- will a 400's plates (or a 550's) work in the 500? Is there a brand you recommend?
2) I'm not sure how to use the grease nipples on the bike -- are they inlets or outlets? How do I lube the tranny, and how do I grease up the lifter bar as you recommend?
3) What kind of grease do I use?
3) What indicates when I need a whole new clutch, or new clutch plates, or a new lifter rod, as opposed to just when I need new clutch springs? And how do I know when I need a new clutch cable?
I'm writing because I have three symptoms: the clutch handle is hard to pull - it works, but it hurts to squeeze; also I'm getting some false neutrals, usually between 1st and 2nd; and finally the clutch makes a BIG clunk whenever I downshift.

Thank for spreading the knowledge!

-Scott B.
Portland, OR

[SteveD CB500F]

Benj - I can write on some of these.

Grease nipples are for squirting grease into - use a grease gun.

The transmission is in the wet sump. As long as there is oil in your engine, the tranny is lubed!

Hard clutch pull - check cable for wear and replace if necessary

False neutrals could be a sign of wear but most have them somewhere

Downshift cluncks - sorry mate, they all do that!

[csendker]

This is my first bike, and I bought it late last summer. Newbie, but nevertheless, here's my 550 experiences:

I had old, crappy oil, and too much of it.  All sorts of weirdness and ghosts dissappeared when I changed it out.  Oil drips slowed down or stopped, tranny smoothed out a bit, engine ran cooler & better, oil light stays off.

I had a real hard clutch pull until I changed out the clutch cable with a new one, and now it works just fine.  I bought a cable lube thingy, and it just came in.  I plan on keeping all of my cableslube'd up from now on.

I rarely get a false neutral, and then it's more likely to be pilot error than equipment failure.

My down shifts aren't too clunky except when I drop into first, then there's a noticable 'clunk'.  It actually helps me to know if I've dropped one too far when I'm looking for 2nd.

[crazypj]

550 and 500 use different methods of clutch adjustment (and its usually done wrong!) Start by slackening the cable all the way, not just the handle bar end (you can check cable moves freely at the same time) On 550, right side lower clutch cover,  a 10mm locknut and a flat screw sticking through. This moves operating arm inside cover. Unscrewing screw moves internal lever closer to clutch. Wind it backwards(unscrew, counter clock) til it touches and turn back in about1/4 to 1/2 turn, lock up locknut and adjust cable at the cover end. 500 has pushrod through engine and adjusts on left side. Slacken cable and turn the big screw.You should use a special tool with a radiused (SP?) end but a piece of flat steel with a radius filed on it works ok. (loosen lockbolt first, 500's always seem to have chewed up adjusters)
Best thing I've found is to fit heavy duty clutch springs, you can easily get 100,000 miles out of plates. If the adjustment is done correctly the clutch pull is not significantly greater than stock.
550 also has a second oil pump which very few people seem to know about. Its built into the output shaft bearing on the right side, thats the reason for the small oil line from the oil pickup screen.
PJ

[HondaMan]

Hello HondaMan,
I'm a newbee -- tryin' to soak up all I can. You seem to know a lot about the 500 clutch -- I have a real clunky one. I'm wondering a couple things, maybe you can clue me in to a couple of basics:
1) Can I swap out the plates for any other size cycle -- will a 400's plates (or a 550's) work in the 500? Is there a brand you recommend?
2) I'm not sure how to use the grease nipples on the bike -- are they inlets or outlets? How do I lube the tranny, and how do I grease up the lifter bar as you recommend?
3) What kind of grease do I use?
3) What indicates when I need a whole new clutch, or new clutch plates, or a new lifter rod, as opposed to just when I need new clutch springs? And how do I know when I need a new clutch cable?
I'm writing because I have three symptoms: the clutch handle is hard to pull - it works, but it hurts to squeeze; also I'm getting some false neutrals, usually between 1st and 2nd; and finally the clutch makes a BIG clunk whenever I downshift.

Thank for spreading the knowledge!

-Scott B.
Portland, OR

Sorry for the long lag: been on the (business) road.
About the clunking: this comes from the tranny, not usually from the clutch. If the clutch plates are a bit warped, it can also happen, but here's the symptoms:
1. Cold: all of them clunk.
2. Warmed up: the neutral-to-first shift will usually clunk. This is because the plates don't really slip across one another until the countershaft is held still. When entering the shift, the shaft is still spinning, and the clunk is that inertia dropping away.
3. If it clunks, or is "sticky" about going into gears 3, 4 or 5, then the plates are warped a little, or the bike has been sitting a long time. This squeezes the oil out of the friction material, making the plates grab each other too much until the oil re-spreads and soaks in some more.
4. If you park it for long periods of time, don't go for stronger clutch springs: this makes it worse. Instead, get clutch plates that are "square-cut" on the friction surfaces instead of the original "slant-cut" style. Both are widely available.
5. Try changing the oil at 500-mile intervals for 3 changes. This will recondition the clutch you have and make it smoother.

I am not a big fan of the Barnett "hi-friction" plates in the CB500 (or the "big four", for that matter), because the plates are slightly thicker and aggravate the already slim adjustment range situation. This is a little better in the CB550, but the square-cut plates fix all issues without the extra expense. Unless, of course, you're a drag racer, then get heavy springs, Barnett clutch and thin down the steel plates - oh, and add about 20 HP or they'll kill you at the track...

 

[ErikP]

thanks for the info!

Curious - are you saying the honda friction plates are square, or some aftermarket parts are?

Is something like this what you mean by square cut vs slanted:

http://www.oldbikebarn.com/part.php?id=615&subcategory=Clutch%20Kits&bike=CB500&DisplayPerPage=10

?

Just trying to figure out what to actually buy based on the info

Thanks!

-Erik

[crazypj]

 They're warped if you have 10,000 miles on them, believe it.

On 550, I have well over 100,000 on the stock clutch and I've done an awful lot of dumb stuff over the years. 
The ONLY modification was to fit heavy duty clutch springs. I fitted 400F handlebars as I prefered the sligtly lower riding position and re routed the cable slightly. Apart from that, make sure its properly adjusted. Undo the lock nut on right cover and UNSCREW the slotted adjuster until you feel contact with release mechanism ( your backing the adjuster into the pressure plate)
The 500 uses a different type of mainshaft in transmission and so adjusts differently, but its possible to make them operate very smooth and easy.
(unless we had different stuff in Britain compared to USA?)
PJ

[Mule Train]

Thanks for all the info guys!!
   My clutch works great for the first 30 or so miles and then goes straight to hell. As soon as the bike warms up it becomes really difficult to get it going. Clutch chatters and it is very difficult to find the "sweet spot" on the clutch as i  release it.  Some friends thought the springs need to be replaced. Any suggestions. this is for a 72 Honda cb 500. Should i just replace the whole clutch? part numbers or kits? thanks !

[dr. destructo]

whats this talk of grease fittings for the clutch lifter?  I cant find a grease fitting anywhere, and my clymer manual never mentions anything about zerk fittings either.  If my bike has zerk fittings, I'd love the use them!

i have a  76 550, and my clutch has issues too.

[TwoTired]

It's only the 500 that has the clutch actuator grease fitting.

[HondaMan]

Thanks for all the info guys!!
   My clutch works great for the first 30 or so miles and then goes straight to hell. As soon as the bike warms up it becomes really difficult to get it going. Clutch chatters and it is very difficult to find the "sweet spot" on the clutch as i  release it.  Some friends thought the springs need to be replaced. Any suggestions. this is for a 72 Honda cb 500. Should i just replace the whole clutch? part numbers or kits? thanks !

Sounds like you've got warped plates. This could be either the steel ones or really severely worn cork ones, but the 500/550 doesn't usually wear the cork ones all that much. However, if a PO had a sticky clutch cable and used it that way for a long time, it could have caused the steel plates to warp. Take them all out and check for flatness, them buy new ones as needed.

[m00ntan]

Thank you Hondaman,

It took me twenty years to find a burned up clutch to play with.  I don't know inside from outside.  I put the friction plates in any which way, and you know what I got.

CB750K4

The Barnett kit I bought has slanted friction cork.  When I pull the basket again, I think I need to stack all of them with the outer slant against the oil sump and the inner slant to the shaft, unless I want to drag race.  At the bottom of the basket, the outer slit would be to the rear
and the inner would be to the font.

The old plates are the type you recommend, but they look like toast.

Can you help?

[bryanj]

"square" cut plates are those from a CB450 twin just so you know and the oly "jerk" grease fitting on a 76 550 is underneathe the swing arm and real fun to get grease into!

[HondaMan]

On 750 thru K6, the normal Honda ones were square-cut corks. I have heard rumors that the later K7-K8 models had slanted corks, but can't verify this, as I haven't been inside one of these later ones' clutches.

Does anyone know if the K7-K8 plates are the same physical size as the K0-K6? If so, I suspect Honda was applying the 500/550 trick to the plates to reduce the suddeness of the 750 clutch when they got to the last "K" series.

I do remember how much the Honda dealers urged Honda to "return to the voluptuous look" of the 750, citing the runaway Kaw and Suzi sales of similar-looking bikes. I think that mostly it was Cycle magazine that didn't like the "F" models, because the owners sure did like them! Then, the later "K" was touted as being "the culmination of the 750 engineering", a blending of the increased "F" power with the "ride" of the original "K" (whatever that meant.     ). One of those things was "a smoother feel", which to me, intimated an improved clutch action....but you know Wall Street.

[Mark M]

The 750K7 clutch is much smoother as is most of the rest of the bike - longer and heavier all round. It's not a bike to be rushed arround as it just feels nice in 'cruise mode'. So the extra power it has on paper is lost on me.

[jph550]

Benj - I can write on some of these.

 . . . False neutrals could be a sign of wear but most have them somewhere

Downshift cluncks - sorry mate, they all do that!

When I end up in a false neutrral, either by rider error or the occasional slip out when riding under low load,  there will be a clink, grate sound when I put it back in gear at speed.
Is this a sign off the clutch being out of adjustment? I try to letting the engine come down a little in revs before putting it back in gear. Should I do the opposite, or something different?
I worry about ripping up the gears.

any help is appreciated,

Jason

[HondaMan]

When I end up in a false neutrral, either by rider error or the occasional slip out when riding under low load,  there will be a clink, grate sound when I put it back in gear at speed.
Is this a sign off the clutch being out of adjustment? I try to letting the engine come down a little in revs before putting it back in gear. Should I do the opposite, or something different?
I worry about ripping up the gears.

any help is appreciated,

Jason

The gears will be OK. It's the gear dogs you are hearing.
Usually, some wear on the shift forks, plus a slight bit of clutch plate warpage, make the combination that creates false neutrals. While not serious, it can be annoying. If you take it apart, get new clutch plates and new shift forks (and maybe a shift drum, if you can find one) and install them for a brand-new feeling again.

[jph550]

honda man,
thanks for the response. its good to know its not something i have to take care of right away. it doesn't fall out too often.

I tried adjusting the clutch before and it was not very inuitive to me. Lining the mark on the lever arm was difficult and there didn't seem to be much travel on the adjuster screw ('76cb550) on the side. I don't have trouble shifting, (except out of neutral when the bike is on the hot side)

It's mentioned you can back out the adjuster screw till it bottoms out then turn back 1/2 to 3/4 turns?? like I said, there doesn't feel like there's much play in that adjustment screw is there something I'm missing.

550 and 500 use different methods of clutch adjustment (and its usually done wrong!) Start by slackening the cable all the way, not just the handle bar end (you can check cable moves freely at the same time) On 550, right side lower clutch cover,  a 10mm locknut and a flat screw sticking through. This moves operating arm inside cover. Unscrewing screw moves internal lever closer to clutch. Wind it backwards(unscrew, counter clock) til it touches and turn back in about1/4 to 1/2 turn, lock up locknut and adjust cable at the cover end.

since i'm still new to this game I don't intend on tearing too far into a good working bike. Though, I would like to get the clutch adjusted the best I can though. Maybe I'll replace the clutch plates and assorted elements in the HOT 2 or 3 weeks of the summer.

my next tasks are to check the point gaps and set the timing, replace fork oil (twice 2-3 weeks apart to flush it, I don't know when it was last done), get a 7/8" master cyclinder for dual disks hooked up and maybe stainless lines (depending on my budget), polish clean and arrest any small rust spots and maybe take care of cleaning and arresting any rust on the bottoms of fenders.

Last spring I did tappet adjustments for the first time and replaced the breaker plate and set the timing. put on a set of new dunlops, ( great recomendation HondaMan), tubes, and a new rubber tire strip to replace the strips of duct tape inside the rim, (with tire irons even.) bought a grease gun and greased my nipple for the swing-arm, replaced the clutch and throttle cables, had the carbs synched by a friendly mechanic , ( one of the adjustment screws had become loose and it was all out of wack), oil change, oil screen replacement, snapped my first bolt on the oil pan and order a complete replacemen bolts set from Western Hills Honda, new air filter, of course spark plugs, rebuilt dual disk calipers, new pads from honda (came with the needed anti squeak nylon waser), new bleeder screws for calipers, replace the oil seal on gear shift, learned to pay attention to how things come off when I removed the front sprocket, (thanks for the help on getting it back on guys), clean a faulty solenoid switch for electric start, cleaned some wiring with waiting for a new plenum box i needed before the carb synchronization. I had to take so much stuff off to get in out and the on again anyhow.

i can't wait tll its a lttle warmer and i can get into my unheated garage more often and tear into it before the spring is in full force.

peace,
jason

[HondaMan]

If the gearbox is sticky when hot, try either a heavier oil, like 20-40 or 20-50, and forget the 10-40. I am a big fan of Castrol GTX oils in the 750/500 engines, because their mineral base holds up well in the transmissions, better than many other oils. The clutches like the mineral-based oils, too, but it will take at least 2 changes at full intervals to wash out the stuff you might have been using before (from the clutch corks).

[straat-toe]

Hi Guys.

Sorry to jump in on this topic so many years later. I was just wondering what the ideal groove depth is on the the clutch plates. And the recommended length of the clutch springs?

Thanks.