clutch not engaging and dragging !!

[bluemouse1006]

 
Hi

I've got my 750K started now and rode it yesterday !!  only thing that's a problem is the clutch no matter how I adjust the cable or plunger in the casing the clutch doesn't seem to disengage fully,all I seem to do when adjusting the cable etc is move the bite point , when you pull the clutch it feels ok but when you select 1st it clunks forwards and starts to move the bike,then of course changing up or down when riding gets tricky, and of course when you stop you cant get it back into neutral.
When I bought the bike from a A*se on ebay I stripped the clutch only to find it was missing (the plates basket and everything) I bought another on Ebay.

When I came to fit it I had to take out the black splined washer as it pushed the whole clutch assembly too close too the casing and the engine wouldn't turn over. Once the washer was removed it was fine and there was a clearance.
Is there a way the plates fit a direction of rotation etc as I cant remember looking for that do they have to sling oil off to work ?

I also remember that between the clutch plates where thin metal plates and one thinker metal plate all I did was put it where it was in the clutch when I got it in the box from the seller ,I couldn't find a picture of a clutch with this extra thick plate although without it Im sue the plates would be too slack in the cage.
should I try and slip the clutch when riding to free it up or has anyone any ideas


Thanks again 

Amos 

[mick]

Glad to hear you have got your bike up and running again  , i have a F1 engine in bits at the moment if you need any photos of the clutch etc,

also found this for you it might help  , cheers Mick.

http://www.cmsnl.com/honda-cb750-four-k5-usa_model483/partslist/E++09.html

[bluemouse1006]

Mick

Thanks for the link the photo doesnt show the one think plate (metal) if you have one in bits photos would be great of it in the right order

Thanks Amos

[Bryanj]

The thick plate was a later modification, if i can find the bulletin about it i will scan it and put it up BUT having said that ALL the bulletins are on the US board somewhere

[bluemouse1006]

Hi
Been in the garage again this morning !!! stripped the clutch again and found that the clutch centre had been catching on the outer shaft centre. this is because I had to remove the splined washer to get the clutch to fit in the casing other wise the casing when tightened down pushes against the clutch centre body stopping the engine turning !!
Ive attempted to down load some photos hope they shed some light. if anyone has a clutch out of their SOHC 750 can you measure the clutch centre from top to end of splines (50mm on mine see photo) the boss at the end of the clutch centre (10mm on mine)

The whole problem seems to be the splined washer pushing the clutch assembly to far out but this washer has a job to do so has to be there ! I did buy the clutch off Ebay so cant be 100% sure its the correct one for my bike ? cant be right if its too big or is it ? with the washer in place the centre locking washer and nut doesn't tighten the shaft flush if you know what I mean (surprise about the same thickness as the splined washer)

 

would appreciate some advise

Thanks Amos

[Bryanj]

All i can suggest is go to the motogrid site mentioned elswhere and look uo the F1 clutch, which i seem to remember was the first with the thicker plate, then compare part numbers tp earlier bikes, if different chances are they won't be a direct fit UNLESS the earlier number "Superceeds" to the later one

[bluemouse1006]

Thanks for the info

Ive looked on the web site (motogrid)  and it seems that there are different clutch centres and outers depending on the engine number etc although I have no idea how to tell if mine is correct for my bike .. anyone know if there are size differences if there is then it might be my prob
if anyone can measure their clutch inners as in my photo then I might be closer to the answer

thanks Amos

[mick]

Hi Amos, as promised heres some photos of the clutch out of a F1 engine i cant vouch that its not been messed with it, these are in the order i took them out,

there are 5 single steel plates ,1 double steel plate & 7 friction plates, hope these help if you need any more just ask  , cheers Mick.

[bluemouse1006]

Mick

Thanks for the fab photos !!!! by the looks of it I have a F1 clutch as the measurements are the same as yours?
My engine number is CB750E 2560081 . is there anyway of telling what age bike that is from ? as the engine number on my V5 isn't the same as this ! so wondering what age is the engine is and if its actually from a CB750K ? if it is then im assuming the clutch is different on a K to a F1 ?
Anyone out there got a K clutch they can measure for me to defiantly rule out or confirm the wrong clutch theory..

I hoping to go down to Donnington Park on Saturday to the vintage jap bike show, I will look around for a K clutch assembly there 
and take my verner calipers to measure up and if smaller buy there ..

Thanks again from a very confused 750 owner 

Sorry if this doesn't make sense but just come in from a night shift !!!!

Amos

[kettle738]

According to this very informative posting       http://www.sohc4.net/?p=111

If I'm reading it correctly you have a CB750F1 engine.

Mick...........kettle738

[mick]

Have to agree with the other Mick according to your engine number its a F1 , if you need anymore info or photos just ask my engines going to be in bits for a while yet  , cheers Mick.

[bluemouse1006]

Mick

Thanks could it be I've thought I had a K engine and bought a K clutch from ebay not realising I have a F1 engine in my bike
The first photo on this post is the width of the splined outer clutch section. Mick on your F1 clutch it seems that yours is 40mm mine measures 43mm
The second one is the depth of the splined section this measurement is 23mm, the splined section on the gearbox  (third photo) with the splined washer fitted is 19mm which the difference is about the thickness of the washer !! which is where my problem is as when I fit the washer it pushes the whole clutch too close to the casing causing it to catch.
all the measurements of the clutch bits seems to suggest that it is too big to fit in the hole !
Mick I know its a pain could you take the measurements re my photos on this post and let me know what you get. if yours ends up to be smaller than mine which I would hope to be about 3mm then that's my answer and ill look out for a F1 clutch assembly if not then it a gallon of petrol and a match wafting it with the insurance documents ha ha

cheers Amos

[Bryanj]

Sorry folks, according to the HondaMotorcycle Identification Guide 1959-2000 (part number 2GMAS00-AH should you want one) The F1 engine starts CB750FE-2515094 onwards and the CB750K'76 starts CB750E-2428762 onwards So as its missing the second F it ought to be a K6.

Now Honda are not perfect with there publications and it is a US guide so its a guess here.

When you go to motogrid and get the part number , put it into the part look up side on the right then click the modles link and it will tell you all the bikes the part is used on. Having done that for the clutch centre you get

CB750F A MOTORCYCLE, JPN, VIN# CB750F-1000002 TO CB750F-1015054
CB750F A (76) MOTORCYCLE, JPN, VIN# CB750F-2000003 TO CB750F-2022317
CB750K A (76) MOTORCYCLE, JPN, VIN# CB750-2540001 TO CB750-2575894
CB750K0 A MOTORCYCLE, JPN, VIN# CB750-1000001
CB750K1 A MOTORCYCLE, JPN, VIN# CB750-1044650
CB750K2 A MOTORCYCLE, JPN, VIN# CB750-2000001
CB750K3 A MOTORCYCLE, JPN, VIN# CB750-2200001
CB750K4 A MOTORCYCLE, JPN, VIN# CB750-2300001
CB750K5 A MOTORCYCLE, JPN, VIN# CB750-2500001


So it would seem they are all the same till you get to the F2 in 77

[bluemouse1006]

Good bit of research there

Im told that I have a F1 engine and the frame number of my bike is CB750-2106706 does this still make sense as the engine number is as you say CB750E-2560081 ? a K
still cant understand why the Bl**dy thing doesn't fit !!!!! everything is there as in the manual and how the photos posted on this site show.
any measurements of the centre boss and the shaft in the box (the only two things that would determine the position of the clutch ) would be much appreciated

Thanks again

If mine is too big then Ill either file the few mm off or when at Donnington this weekend look for another

look forward to you comments again


Amos

[mick]

Hi Amos i managed to get some more detailed photos i hope you can understand them and they are of some help  .




2 measurements from the centre  1st one is on the shoulder & the 2nd is dropping into the splined middle (hope you get that part).