Topic: Clutch slipping.

[Korven]

So to describe the problem, Clutch is slipping in to gear while being a little more Throttle friendly. Its a cb500 with slight increase in hp. Using a Q8 SBK RACING 10W-50 Oil. Its marked API SM, JASO MA2, ACEA A3. Same oil as they are using while racing the 350s

So saw that there were some other threads about this mostly where it was suggested to go with the oem clutch plates. Hondaman prescribing  "plates are available with square-cut cork faces."
Where do i find those? So i got myself a spare clutch basket to try out the oil hole mod thats. Anyone have any opinions about this one, perhaps done it yourself? does it provide any better gripping?
Hondaman also describes that the plates (the steel plates?) are warping after 10000 miles. Do i inspect them for warping or just go for new ones right away.

[dave500]

have a close look at the adjustment first,take the left cover off that houses that cork screw release mechanism,be sure its not worn so much you get as much vertical movement before its begins the lateral movement,be sure the rod isn't broken,youll never be able to adjust it correctly if that mechanism is worn out,the oil hole mods wont do #$%*.

[PeWe]

CB750 related that might be similar on CB500:
I have that oil in my CB750 K6 (1000cc 90+ hp) without slipping, mixed with Red Line 20W-50. I had slip before that was caused by the adjustment as Dave mention, but on the CB750.
The adjustment on a CB750 is easy to do wrong. The screw should be tightened until stop and opened 1/4-1/2 turn.

I have noticed that it will first stop at a soft stop possible to tighten harder.
When the screw is really bottomed, it must be opened 1/2 turn.
If stopped at the first resistance, OK to open 1/4 turn.

The clutch package and play change when engine is really warm. If you adjust when warm, the clutch lever at handle bar will be very tight when cold, no play. Thats is how both my CB750's are. I adjust at every ride. Have to stop doing that....

My CB750K2 have Spectro HD 20W-50 mineral oil. It got real dragging clutch, not enough to rock bike with clutch lever pressed, forward-backward to release. I start ENGINE and it will creep forward Until engine is warm.
Much better now after it has got 2L replaced with the Q8 SBK 10W-50 racing and Red Line 20W-50. I'll contiune to mix Spectro with SBK racing that is very cheap (at swedish Swedol) for a Synth oil or for a good oil in general.

[dave500]

forget about the #$%*ing cb750 adjustment procedure it don't matter here!forget about the #$%*ing oil also don't confuse Korven its not applicable!forget about #$%*ing racing oil who gives a #$%*?if that cork screw is worn out itll need to be replaced youll never get it happy to use if its worn,the later 550 had a totally redesigned clutch and release mechanism to fix the problem.

[Deltarider]

Depends on the model. I see Korven is in Sweden. The European K2 had the modified and ever lasting corkscrew. Wouldn't it be nice if all posters would name their bikes by their proper name, the name Honda gave them and Honda did not talk years... The 'year' is an American marketing invention.

[flatlander]

korven, check the adjustment first as dave says.
do you have the honda shop manual for your bike? it's described there how to adjust the clutch. try that, and let us know what the effect is?

[evinrude7]

did the clutch hub mod on my 750.  happy with it. 

[Korven]

I have the K1 model with the pushrod. I will try to adjust first. The pushing rod is in one piece. EVerything been cleaned and used alot of grease both while mounting and in the nipple.To describe the problem further. Its like when im im shifting at 8000 rpm or so it takes 2 seconds after letting the clutch out before it engages 100% and the rpm drops to 6000. I cant remember right now how much play i have in the handle but around 10-15mm i think. Wire is new.

[Henning]

forget about the #$%*ing cb750 adjustment procedure it don't matter here!forget about the #$%*ing oil also don't confuse Korven its not applicable!forget about #$%*ing racing oil who gives a #$%*?if that cork screw is worn out itll need to be replaced youll never get it happy to use if its worn,the later 550 had a totally redesigned clutch and release mechanism to fix the problem.

Eloquent as always, Dave 

If all else is in order could be that the clutch springs are shagged. You can fix that on the cheap by putting a washer behind each spring. I've done that on - dare I say it - a 750 

[Korven]

Would you consider this worn out or is it normal? Manual does not cover any specs or service on this.

forget about the #$%*ing cb750 adjustment procedure it don't matter here!forget about the #$%*ing oil also don't confuse Korven its not applicable!forget about #$%*ing racing oil who gives a #$%*?if that cork screw is worn out itll need to be replaced youll never get it happy to use if its worn,the later 550 had a totally redesigned clutch and release mechanism to fix the problem.

[flatlander]

dunno, this bit is 500 specific.
you'll need to fire up the batlight to call dave 

[bryanj]

Yes thats excessively worn and the centre mod is 750 only. 500's are notorious for slipping clutch on takeoff or gearchange as long as it dont slip when you just open the throttle live with it

[HondaMan]

This sounds to me like the clutch plates just need to be changed to the square-cut variety. Measure the thickness of your plates first: most of the 500/550 plates are 0.128" thick when new. This is important, because many that have been sold in the last 8 years or so have been too thin. on the order of 0.108" because they look similar, but are for modern superbikes with more plates. That said, is you want to spend the time and money to experiment a little bit, you can fit an extra plate into the stack if you get the right ones: I have done this on the 550 several times. You must also get the thinner steel plates to go with the thinner cork plates in order to make this happen, but it works great when you make 605cc engines of the 550.

[dave500]

be sure to use old fashioned basic engine oil,the 500 clutch was much improved in the 550 and in fact totally new and different,roughen up the steel plates,new friction discs and perhaps heavier springs is the the best that can be done for the 500,if the problematic cork screw release is in good order,be sure the cable is slick and not binding,routed correctly?the later 550 bottom end really sorted and addressed some ongoing issuses over the 500.

[Korven]

Thanks for all the replies. I think also that the corkscrew might need a change. While pulling the clutch you can feel a few "stops" on the way its like its gettings catch just slightly on the way out. that might be imperfections in the cork screw tracks due to it being worn? the wire looked fine but changed to a new one just incase. I will pull the clutch pack out and measure wear, thickness and warping of the plates. As for the correct friction discs, does anyone have a link for the ones that hondaman is specifying or am i fine with getting from david silver? Im going with a new standard clutch with the standard amount of discs for this bike. if it wont work i can always use them in my other stock 500. I have a new cork screw laying around but do i need the adjuster piece aswell?

 https://www.davidsilverspares.co.uk/CB500K0-FOUR-1971/part_4236/   - discs

This sounds to me like the clutch plates just need to be changed to the square-cut variety. Measure the thickness of your plates first: most of the 500/550 plates are 0.128" thick when new. This is important, because many that have been sold in the last 8 years or so have been too thin. on the order of 0.108" because they look similar, but are for modern superbikes with more plates. That said, is you want to spend the time and money to experiment a little bit, you can fit an extra plate into the stack if you get the right ones: I have done this on the 550 several times. You must also get the thinner steel plates to go with the thinner cork plates in order to make this happen, but it works great when you make 605cc engines of the 550.

[flatlander]

i would recommend getting the oem honda plates. check the serial number of your engine, then look up in the parts list what parts numbers for the plates and discs match it, and get those.
that is your safest bet. with aftermarket clutch parts you never know if they fit well because these clutches went through slight modifications over the production period of the engines.
of course if the exact parts for your engine number are no longer obtainable then we need to start looking at alternatives but try that first.

[HondaMan]

Honda's plate number is: 22201-KY2-000 . This is a 0.122" thick friction plate, which the 550 also used. Many aftermarket parts are either 0.138" thick (CB750) or 0.108" thick (not for these bikes), but both of these 'other' plates frequently get sold to this bike. Don't let that happen: if the 0.108" plates are installed, the clutch will slip, almost immediately. If the 0.138' plates are installed, it will not go back together, the stack will be too tall, and overtightening the bolts can then break the pressure plate(!). Don't do that...