Topic: cb750f clutch slip: inspect, replace? brand suggestions? general clutch talk

[catsoup]

1978 CB750F, 26k miles, stock air/carb/exhaust, electronic ignition with martek coils

So I've been doing what I think are fairly intelligent/conservative updates to my bike lately. In the past few months I have had Hondaman update my swingarm, new Hagons in the rear, progressives in the front, and Tarozzi fork brace. I execute fairly good (I think) periodic maintenance, and the bike runs very well. I have two known issues, one of which I feel prepared to tackle now (despite it being riding season in TX/AZ).

The bike occassionally slips in 4th gear, sometimes it will fail to engage while up shifting - sometimes it will 'fall out' soon after engaging 4th gear. also sometimes neutral takes a second to find but this doesnt seem abnormal I have not done any clutch adjustment, so obviously I will start there, checking the cable and checking the adjustment screw. I will probably pull the clutch to add the extra oil holes as recommended by Hondaman. While I'm in there, my question: having never pulled the clutch, should I just go ahead and order plates and springs? or should I open it up and maybe deglaze/reinstall (depending on what I find).

Within this question, if I replace, what should I replace with? I don't have any particular issues with the engagement, though I'm always up for improvement. I noticed Cycle X has their standard plates on sale right now ~50$ for the plates, gasket, and kickstart rubber ring. Seems affordable. Other options seem to be Honda Genuine (expensive) versah/barnett (mixed reviews), or generic "oem" from the internet (mystery???) And then springs... same caveats apply.

Am I going about this in the right way - I suppose this could be a transmission issue, which scares me a bit. not excited about cracking the case yet. maybe next time Im deployed I can have someone do that. I do plan on replacing some of the o rings in the oil pump/shifting mechanism next oil change.

these are the clutch inspection steps I plan on using... http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html

The other issue is minor oil leaks from the top end gaskets... not ready for that.

[flybox1]

The easy stuff to check/replace: Cable tension, metal plates, cork discs, oil.
The hard(er) stuff: Worn/bent - shift drum, shift forks, transmission gears/dogs.

If you replace cork plates, choose HONDA brand straight cut corks.  The aftermarket angle cut ones, as Hondaman has mentioned in the past, are less than idea when it comes to oiling.

[madmtnmotors]

If you replace cork plates, choose HONDA brand straight cut corks.  The aftermarket angle cut ones, as Hondaman has mentioned in the past, are less than idea when it comes to oiling.

I just purchased original Honda friction disks from Honda Parts Nation and can make the following observations:

>Friction disk "A" Honda part #22201-371-000 has been updated from the original design and now has angled cuts (six required)
>Friction disk "B" Honda part #22202-392-000 originally was the only slant cut disk in the pack (one required) is no longer available from Honda  . This is the outermost disk and would have wider tabs to properly fit the later model clutch basket.

[flybox1]

If you replace cork plates, choose HONDA brand straight cut corks.  The aftermarket angle cut ones, as Hondaman has mentioned in the past, are less than idea when it comes to oiling.

I just purchased original Honda friction disks from Honda Parts Nation and can make the following observations:

>Friction disk "A" Honda part #22201-371-000 has been updated from the original design and now has angled cuts (six required)
>Friction disk "B" Honda part #22202-392-000 originally was the only slant cut disk in the pack (one required) is no longer available from Honda  . This is the outermost disk and would have wider tabs to properly fit the later model clutch basket.

I wonder if they are just packaging these in HONDA bags? 
Keep us posted on how they treat you.

[Don R]

 Adjust the clutch lifter and cable before you get too excited. Sometimes an oil change will make a difference too.

[madmtnmotors]

If you replace cork plates, choose HONDA brand straight cut corks.  The aftermarket angle cut ones, as Hondaman has mentioned in the past, are less than idea when it comes to oiling.

I just purchased original Honda friction disks from Honda Parts Nation and can make the following observations:

>Friction disk "A" Honda part #22201-371-000 has been updated from the original design and now has angled cuts (six required)
>Friction disk "B" Honda part #22202-392-000 originally was the only slant cut disk in the pack (one required) is no longer available from Honda  . This is the outermost disk and would have wider tabs to properly fit the later model clutch basket.

I wonder if they are just packaging these in HONDA bags? 
Keep us posted on how they treat you.

They look pretty legit. I've had good parts results from them after numerous orders. We have a member here that lives near them and has dealt with them personally with good results as well. I have no reason to believe that they are "repackaging" aftermarket parts into Honda bags...

[catsoup]

Adjust the clutch lifter and cable before you get too excited. Sometimes an oil change will make a difference too.

This is my approach in general, though the issue has persisted through oil changes - and I have adjusted the clutch in the past, just probably not in a few thousand miles. Also Im planning on drilling the hondaman oil holes anyway, so I'll be in there.

Is there another source for genuine honda parts that people prefer? If Im going to end up getting the slanted blocks from honda whats the next best option for square blocks

[PeWe]

I had clutch slip for many years ago due to the oil. I used car motor oil that has friction modifiers like moly....When I slammed in the 5:th gear in around 170-190 kmh followed by WOT, I could release throttle a lttle and WOT again and it sounded like shifting to 6:th gear. Beginning of 80's no problem with the car oils I used, worse after 1985.... Castrol GTX2 rather OK followed by GTX3 and worse with Mobil 1 that is a good oil for cars.

Use motorcycle oil made for wet clutch. If using add-ins with zinc etc, check for anti friction stuff, MoS2...not good for clutch.

[catsoup]

Probably should have put this in the original post, I use conventional motorcycle oil without detergents etc, and change oil within recommended intervals. I have never run a zinc add-in through it.

[ekpent]

 If it is gently popping completely out of 4th gear all by itself,especially under a load then you probably have more problems than just your clutch. Could be a worn transmission, gear dogs etc. if that is the case. 2nd gear is more common but have heard of problems with 4th also. Hopefully I just misinterpreted your initial post.