The International CBX Owners Association

Thanks Dave, and please note, the spring in the background is NOT new as I reported, but AS NEW.
My engine has done about 35,000 miles and have noticed, some springs are as new in this department and some, 'worn' as in the pic above.
Must have something to do with the springs rotating slightly under compression ...
I do have quite a few NOS springs but hate to throw away perfectly good parts; so much more satisfying to make an informed decision.
Cheers, Aris

Aris:
Of the 12 exhaust valve springs, with 38,000 miles on them, only 2 had very minor scuff marks on the head side. The others were as new. I'm sure you confirmed the presence of all of your seat washers. Can't think of why many of yours look as they do. I suppose I'd replace those if you have new ones.

Dave

Dave, my fault, thought it was evident from my photo.
The wear shown is on the cam side, NOT the head / seat washer side of the outer springs.
Head / washer side for all outer springs is OK, with few and minor scuffs like yours.
Aris

LET THE REAL FUN BEGIN!

OK chaps, after almost 2 months of detective work, dismantling, assessing, heartbreaks, cleaning, discarding, 100's of pics and mostly your huge support, I am now ready to start putting my engine back together.

Everything is assessed, everything is super clean and measured for tolerances, some parts replaced, my crank is on the way home from England, and I have everything I need to start and (hopefully) finish a rebuild which will lead to a good engine and a markedly more worn out if wiser owner.

MOST OF ALL, I NOW KNOW WHAT WENT WRONG.

So we begin with the head ... But ... not so fast.
I have just decided to take a holiday so will stop right here and restart the project when back, around July 12.

Stay tuned, and once more THANKS EVERYONE for your outstanding support.
Aris

Aris on holidays?
I hope this does mean i have to start working on my own bike instead of watching you. I know my work will not be nearly as productive.
Happy Holidays.

Aris,
Thank you for one of the best and most enlightening threads I have ever had the pleasure to read.
Very Best,
Phil

Kool_Biker wrote:

daves79x wrote: As for installing new seals - find a Phillips screwdriver that will easily pass through the guide. This will be your mandrel. Then take an appropriate 1/4 drive socket and slip it on the screwdriver shaft, followed be a greased or oiled seal. The socket is just a spacer. Now insert the shaft into the valve guide and gently push and twist and the seal will pop right on. You can do them all in about 5 minutes this way. I know, a photo would be nice, but it is agony for me to what you do with the photos, Aris! Probably a poor description, but that's it.

Dave

Back to rebuilding my engine and here's a pictorial amendment to your description, Dave, on how to install valve seals.
All of mine went in with a most satisfying 'thud'. Cheers, Aris

Hi all!

I have disappeared, as various commitments and of course summer have interfered with rebuilding my ailing engine.
But I have managed to do a bit of work lately:
My clutch is now fully refurbished and assembled - hopefully no more rattles at idle, and ...
I have just finished the valve train. I've also just received my fully reconditioned crank & conrods from the UK and I am currently cleaning them - that is removing the tons of moly assembly lube on them - to do my OWN measurements , before I begin assembling .. Hope you all keep well.
Aris

... and typically, the very first measurement I did was hiding another disaster.
Although careful measurements of my 6 original rods had indicated a matching between them within +/- 2gm, upon return from the UK together with my refurbished crank (I had sent them along so they big ends could be matched), one of them, no 5 was a full 11 gm less than the lightest one!!! On close photographic inspection it became evident that this particular rod was different to the one I sent. An 'S11' instead of an 'S6'. Following a frantic telephone conversation with the proprietor, I was told that the no 5 rod ' .. was found slightly bent and was replaced by another one ..', inadvertently lighter .. I was never told.

In any case another rod, within my specified weight range is in the post and can't wait to get it ... let's see.

This latest experience of mine only shows how careful one must be with EVERYTHING - never take anything for granted; in fact both my crank and rods arrived packed with moly assembly lube and it would be all too easy for me to go ahead and assemble.

Question: Utube has many interesting videos on how to match rods, e.g. http://youtu.be/QLpiF0E0EJU .Has anyone attempted anything similar on a CBX? Would love to know.

Cheers, Aris

Kool_Biker wrote:
Question to all CBX cognoscenti:

Utube has many interesting videos on how to match rods, e.g. http://youtu.be/QLpiF0E0EJU.

Has anyone attempted anything similar on a CBX? Would love to know.

Cheers, Aris

Aris,

Any progress on this in August?

Barry

Hi Barry

Yes some. Not as much as I would like though... Unfortunately I was delayed by the to-ing and fro-ing of my crank and rods to the UK for refurbishment which involved having to send back a bad (very light) rod which did not match with the rest and had to be exchanged.
But always trying to turn a problem into an opportunity, I was given the time to look, and look again, and finally find, surely and unequivocally, EXACTLY what went wrong with my engine (as reported earlier), giving me the confidence to proceed with my rebuild!
Since last time I posted:
1. The refurbished crank was plastigauge tested in the engine cases.
2. The 6 rods were trimmed and lightly matched for weight 3. They were then plastigauge tested for oil clearance on their corresponding crank webs
4. With everything checking, they were correctly mounted and torqued on to the crank using plenty of assembly lube.
5. The populated crank was offered to the cleaned and appropriately lubed inverted upper case 6. All ancillaries were inserted, and I decided to use a new main chain as mine 'looked' a bit loose as documented aerlier
7. Gear clusters were inserted 8. All important seals were put in place, refurbished oil pump, gear selectors, etc 9. Finally, the cases were closed properly. And this is where I am today.
Assessing pistons, rings and the cylinder comes next! Cheers, Aris

I'm posting this info from Forum member 'bobcat' to Aris, and all:

"I would agree that it is most likely a rod bearing problem (spun) . The reason the noise is most prominent in the top end is because when a bearing spins, the clearance increases
rapidly but there's enough oil pressure and low load at idle that you won't hear it at idle. But when you put a load on the cyl. / increased RPM
what you are probably hearing is the piston hitting the head , thus the top end noise and not a deep "rod knock". If he has the motor apart ,
he should check the perimeter of the piston and combustion chamber for contact or carbon knock off . I wish him well ! He should also have the
crank checked for "flat spotting". Hope this is useful !"

Larry
What you say makes a lot of sense, but:

Regardless of my very extended inspections in all areas you mentioned, I failed to find any tel-tale signs of piston - head - valve contact, around pistons 1 or 2, whatsoever. Small end clearances were within spec too.

Indeed, and despite by now having answered most of 'what exactly happened' questions, this remains perplexing for me; the ding noise was much louder at the top rather than low in the crankcase.

The crank has now been refurbished and I am reasonably progressed in reassembling my engine. We will soon enough know
Best, Aris

Hi Aris,

I've been away for a while and just coming back up to speed on your engine.

From what I've been able to understand the mysterious media injestion into your oil system was via crankcase bearing holder pockets of media in to #1 & #2 connecting rod big ends where glass beads could hide........as shown in this picture. download/file.php?id=477

Am I correct in all this ?

Also, like Jeff Bennets said, I've never seen anyone glass bead the inside of a engine and while I am very impressed with your willingness to do this, it seems it was the start and root cause of your grief. I feel your pain and I hope to see your engine running alive a well very soon.

My best....... Mike