strange fibre on 77 cb 750k6 oil pump filter

[shiny-2-3]

Hello i am a new membe to the forum,i have a couple of questions regarding my 1977 cb 750 k6,i have had the bike about six months,have just changed the oil and filter,and thought i would clean the oil pump filter at the same time,i discovered a strange fibre type substance on the oil pump filter mesh,any idea what that could be,also,in the sump pan were some small black pieces,any ideas what they could be,would not think it could be the chain tensioner as the engine was totaly rebuilt by the previous owner,the engine runs as sweet as nut,with no strange rattles,apart fron the usual clutch rattle,should i be worried as i dont want take the engine out and strip her down,i have also noticed that the oil return pipe has a kink in it near the tank and has flattened,as have herd that the oil pipes can break up internally,coud this be the cause of the black bits,any help would be greatly appreciated.
many thanks
Dave.

[Re-run]

Well dave sorry to say your bike is going to blow up. You should send it to me and I will dispose of it properly!

Anyways, the bike is a 1976 as that is when the k6 was out. A 77 has a different tank and seat and longer wheelbase along with a number of cosmetic differences. As for the fibers, if you can post a pic, that might help. they could be clutch fibers. the black chunks are hard to say. Are they soft like rubber or very hard?

[shiny-2-3]

Hi mate
Thanks for the kind offer to take my honda,but i am afraid i must decline,i promised to love and care for her till death do us part.and i plan to be around for a few more years,the black bits are soft,and were only on the bottom of the sump,nothing in the oil filter,also with the sump off i could feel around and no black bits stuck on the sides of the crankcases,the primary tensioner is as new,the bike was registered on the 17th of january 1977 so i guess it is 76 model.have not got any pictures of the fibre,it was almost like oil soaked cotton wool,not a vast amount.
thanks
Dave.

[Re-run]

I had something like that happen once with the fibers and never again. It kinda looked like cotton from a cottonwood tree, just soaked in oil. The rubber bits maybe came from the old tensioner? I am guessing you just got this bike?

[CB750Winger]

  The black pcs could be from the oil filter seal. Make sure when you take the filter off, there is a flat washer between the spring and the seal. If not, the spring will dig into the seal. When I took mine off, there was no washer and the previous owner had the spring on the wrong side of the filter. The other stuff floating around could be a little gasket sealer peeling off from the inside.    Paul