primary Shaft

[robsgreen]

Hi everyone,
I've recently joined and own a 1979 red italian import CBX1000 which Ive stripped down to rebuild. SEP are looking after the crank and head but just wondered if someone could clarify something for me. The bearing on the alternator side of the shaft is not an interference fit on the shaft as per the bearing on the clutch side. it will slide up and down the shaft with a bit of help. i cannot find a shaft dimension in the manual to check this against. The shaft has no nasty scores or steps in it etc. I'm replacing the bearing anyway but is this normal?

cheers
martin

[EMS]

Welcome to the ICOA forum, Martin!
I really cannot answer your specific question, but from an engineering design point of view, you should no have two fixed bearings on one shaft, if their outer races are seated fixed in the housing.

[robsgreen]

Hi
Thanks for your answer and your warm welcome. i agree but i just though that as the clutch side bearing is fitted into a carrier and bolted in position I'm not sure.
Regards
martin

[daves79x]

Martin: Your bearing is perfectly normal. Just be sure that the opposite side bearing (the one in the carrier with 3 bolts holding it) is in good shape. It is prone to failing under duress from the alternator. I know it's on the opposite side, but the hollow oil-carrying shaft is know to plug up with sludge if the alternator has seized or gotten hot. This compromises the oil flow to that bearing and it fails. I've seen 3 or 4 of them fail and that seems to have been the cause.

Dave

[robsgreen]

Hi Dave
thanks for the info and putting my mind at rest. When i stripped the engine, there was loads of muck and debri in the oil pan and filter strainer. i have to say the worst Ive ever seen on any bike. One of the bearings in the alternator (larger one) had broken up. there was also blueing on the drive plates. i read your thread on a previous post so I think I will strip the bearing off and clean out the oil ways in the shaft as a precaution. the bearing in the carrier runs very smoothly. the one on the alternator side of the shaft is not so good so I will replace.
Thanks for your help
Best regards
Martin

[daves79x]

You should also see a small aluminum button pressed into the end of the shaft on the alt side. This is an oil metering orifice. Many are missing and one can be made, but it needs to be there. You can punch it out from the other side with a long drift.

Dave

[robsgreen]

Hi Dave
I haven't got one of those and cant see them on any pictures of the primary shaft. what do you mean when you say "punch it out from the other side? Is this just to remove one that is there? I presume it is a cap pressed in from the alternator end? sorry for my ignorance on this! can you clarify please
Cheers
martin

[Kool_Biker]

This (pointed to by pink arrow) is the aluminium 'button' Dave's referring to.
Mine had popped out, but was luckily entrapped between the two alternator clutch plates and I caught it almost by luck.
It is too easy to lose down the alternator opening oil return hole (green arrow), so be careful.
It is soft aluminium, can easily be replicated and can be tapped in situ easily enough with a light hammer.

P1110173.jpg

[EMS]

So, here is the million dollar question: If you have converted to a dry drive Kawasaki alternator, which does not need oil, can you plug the hole completely? And if so, what happens?

[daves79x]

I've pondered this also, but have always assumed that the oil feed out of the orifice was essentially 'plugged' anyway by the new coupler attached to the shaft.

Dave

[daves79x]

Martin:

The reason I mentioned punching out the button (if you have one), is to clean out the hollow primary shaft of any debris.

Dave

[robsgreen]

Hi Guys
Thanks for all your help. it seems you start with one problem and end up with another. My big question is now this: I presume this aluminium mushroom presses into the shaft hole, but has a smaller hole to restrict oil flow? if so, what diameter is this hole? if anyone can tell me i'd really appreciate it and can get one made.
Best Regards
martin

[daves79x]

The hole is 2mm or 5/64 inch.

Dave

[robsgreen]

Dave
Your an absolute star,
Cheers
Martin