Topic: 1975 cb550 Project SENCHA - bike has found new home

[goldarrow]

So what's next since you have another project now?

More likely than not I'm going to save the bike. When it's gonna happen? No idea yet. Not sure if it's a good idea to start working on it while the 550 is still in progress.

Today put the o-rings that came with the gaskets kit


The new o-rings are a bit smaller than the old ones would this cause problems?

[CBGhia]

Were there 8 of those in the kit?  They look like the o-rings for the tappet covers.

[goldarrow]

Were there 8 of those in the kit?  They look like the o-rings for the tappet covers.

The kit came with 12 total.  I'm thinking 8 for rapport and 4 for intake...but that's how they look on intake ports

[dave500]

the old ones wouldve been flattened into the groove fully,its the same o ring for the tappet covers and the inlet manifolds.

[goldarrow]

Head is tightened down.  Used pick tool and laced the washer then bolt, helped guided them into the holes.

Tightened down the nuts in steps. First few rounds by hand. Then more rounds using torque wrench. I only have lbs/in type.

1st round 100 lbs/in = 8.3 lbs/ft.
2nd round 120 lbs/in = 10 lbs/ft
3rd round 140 lbs/in = 11.7 lbs/ft
4th round  160 lbs/in = 13.3 lbs/ft
Then last round 170 lbs/in = 14.2 lbs/ft. just shy of 14.46 minimum spec per manual. Realizing that these bolts are old and may be a bit rusty, so I stop there

Also did a couple of kick by hand at the kick start to feel how pistons move. I could hear some compressions noise from the holes. So I think that is a good sign, right?

[dave500]

go a little higher final torque,like 16-18,you wont need to retorque,yeah turn the engine over a few times to make sure theres no binding or valve to piston smash,plenty of oil down the bores.

double check your cam timing marks,and make sure the ignition is set up correctly,it must fire up first time and dont let it idle,blip the throttle untill its warm enough to ride,youll have to vacuum sync the carbs once its run for a little while,change the oil after the first tank of fuel.

[dave500]

have a look here goldy.
http://forums.sohc4.net/index.php?topic=103432.0

[goldarrow]

Thanks Dave. I'll make sure I do those.  The bike is far from running still.

Here's how motor look like at the moment.

[Stev-o]

Motor looks great

[goldarrow]

Thanks Steve, I'm trying.

[goldarrow]

Spent my late afternoon finish up torquing the head.

Increments of 10 Lbs/in, went up all the way to 200 lbs/in = 16.67 lbs/ft which is right at the upper end of manual spec.

Dropping in the 650 cam without any mod to the casting.

My stock cam was pitted badly on several lobes so I had no choice but change it out. Since I'm changing it, might as well go with the performance upgrade. Thank you Onepieceatatime for letting me have your 650 cam.  Also remembered from reading Twotired post about later 77 or 78 550 cam cover will keep the 650 cam at longevity. Something I might do down the road.

Here are some pics

On the left is my set of cam, the right is the 650


This pic 650 cam is on the right.  The cam marked R10 L. The 550 cam marked R10 J. No clue what these means.


Sprocket in comparison, again 650 is on the right


Tach drive gear. Notice that the gears are just slightly more slanted than the 550. This is why you will need the 650 tach drive


Lobe measurement in comparison. 650 cam obviously has longer lobes.




Tach drive side by side


A different view


Installing the cam is fairly straight forward, make sure to follow the manual. Ch.4 no.12, figure no.84. Make sure position chain, sprocket, and cam as pictured

Set valve timing as shown in no.13 and figure 85



Now that you followed the manual, chain and sprocket still won't go on the cam right? Well here's the trick. Not sure if this has ever been covered already but I don't recall seeing from reading.

What you want to do is tighten up the tensioner so that no tensions apply to the chain. Loosen the nut, turn adjusting bolt to the right (don't do too hard or you'll break it) then tighten up the nut.

Now there should be just enough slack in the chain to slide the sprocket onto the cam and bolt on. Make sure valve timing is still spot on. Chain will go on to the sprocket with ease

Once done tighen up the bolt, spin the motor few time and done!


Cover up the rest tomorrow

Edit: forgot to mention to keep using 550 cam sprocket.

[onepieceatatime]

That engine is looking really nice. Glad to see it all coming back together, and looking forward to seeing that you have it on the road.

[goldarrow]

thanks onepiece for your contribution, still have a few things to sort out but sure is coming along.

[goldarrow]

today, buttoning up the top of the engine.

securing the rocker arms using the famous, very well sought after trick for installing the cam cover! THE RUBBER BAND TRICK!  i went extra mile using the colorful rubber bands...lol

here's pic of top of cover


bottom side of cover, all ready to go


applying yamabond semi drying #4 to the rubber seals pucks, it was a bit messy, so later i applied the sealant to the head instead.


and here's the engine buttoned up.  just need to get hex bits so that i can torque the cover down per manual


finishing up the rest of the engine paint, the swing arms next

[dave500]

once the cover is on and tappets set remove the plugs and turn the engine over a few times,make sure the valves dont hit the pistons.

[goldarrow]

One question Dave, how do I make sure oil pump is active and doing its job supplying the oil to the top end?

When does the oil pump actually pumping up the oil? I just want to make sure that oil is feeding it's way up so that I don't have to go back to square 1 and spend money on rebuilding it again because of no oil.

I will probably remove the oil pump for inspection also.

Thanks

[dave500]

good precautions goldy,with the left cover off youll see the oil pump pressure switch,this turns the dash light on and off,remove it and with the ignition off and the spark plugs out spin the engine on the starter and up to about 3 or 4 seconds or instantly oil should spurt out of that hole,refit the sender,then again with plugs out and ignition off spin it again and the oil light should go out.normaly the oil light goes out pretty much straight away when starting,if youve done an oil and filter change it takes a few seconds to fill the filter housing and build pressure.

[goldarrow]

once the cover is on and tappets set remove the plugs and turn the engine over a few times,make sure the valves dont hit the pistons.

I think I have a serious problems!?!?!?! But I hope not. Set timing T mark spot in at the point BUT I have no play at the rockers to adjust!  Intake #3, Exhaust #1,2

Looking at the manual


Reading it over and over like 10 times, I think I'm doing it in reverse than the manual. Basically, i was trying to do the "x" instead of "o" and that's why no play in the rockers? If so, could I simply turn the crank another 360* to free up the rockers?

Here's my 0.05mm feeler now


I hope I'm right, will give another go tomorrow

[dave500]

turn it 360 back to the same mark and try again,or do it the way i always do,ignore the notion of setting a few tappets at a time and do one cylinder at a time in sequence,rotate the engine in its running direction and watch as the valves for #1 move,keep turning and watch as the inlet valve goes down then starts to come up,when its almost closed look at your 1/4 mark and stop it at "T",set both valves on cylinder 1 now,do all the valves like this remembering to stop the mark on 2/3 for those cylinders,,this way you cannot be wrong,no valve will be set with the cam of its base circle.

i have a feeler set where you can remove each blade from the holder,it makes it a little easier to do then,i cut them off blunt and sharpen the blunt end down a little,itll insert a bit easier then.

[goldarrow]

finally, i was able seal up the engine top-end today. 

- valves tappets checked
        well, previously i was having small trouble adjusting the tappets.  trying to do several "o" and "x" at a time was not successful for me as i found out that one of the tappet screws won't go all the way through the rocker arm screw hole like it normally should, it kinda stuck half way.  may be this is something to check before doing installing the cover on the head.  i went ahead adjusting the tappets 1 cylinder at a time both inlet and exhaust. 

starting with
-No.1, turn crank until T mark 1-4 lined up with the case mark, check to see if rocker arms moves up and down a lot or very loose, this is TDC (top dead center) at cylinder 1, then it is ok to adjust the INLET 0.05mm and EXHAUST .08mm.   
-if you check the rocker arms and they are tight, or move up/down very little, then TDC (top dead center is at cylinder 4).  turn crank 360 degrees and make sure T mark 1-4 lined up with the case mark again, this should be TDC of cylinder 1.  then adjust tappets for cylinder 1.
-turn crank case once more 360 degrees, with the T mark 1-4 lined up, this should be TDC of cylinder 4, adjust the tappets
- turn crank case again but this time make sure T mark 2-3 lined up with the case mark.  feel the play on the rocker arms, if the rocker arms on cylinder 2 feels way loose, then TDC is at this cylinder, adjust the tappets.  if rocker arms are tight, TDC is at cylinder 3.  turn crank case 360 degrees and adjust tappets on cylinder 2.
- turn crank case again 360 degrees and this should be TDC of cylinder 3, adjust tappets and you're done.

this is probably not the best write ups, but i was only trying to be a little more precise that what i have read here on the forum and the manual.  hope this helps someone in the future.

- cam chains checked
                 once done with the tappets, adjust cam chain with to its sweet spot.  very straight forward from the manual.  loosen the cam adjuster nut, turn the crank to just past the T 1-4 mark, spring peg just to the right of the case mark.  this is 15 degrees ATDC (AFTER Top Dead Center) sweet spot.  tighened up the cam adjuster nut and you're done.

- points checked
               here following the manual is simple, but trying to see when the crank turns until the point contact opens widest could be tricky to the eyes.  after several turns, i notice that when the points open up the most, the crank is at 15 degrees ATDC.  so i used that as a reference to adjusting the point. someone please correct me if i'm wrong. manual spec is 0.3mm - 0.4mm.  do the same procedure for point 2-3. 

[goldarrow]

droped oil filter, oil pan and clutch cover. 

-changed 3 o-rings on the oil pumps.  of course the screws holding oil pump to the engine won't come off without a fight.  had to use screw extractors on 2 of the 3 screws, and replaced with slightly shorter screws, hope this will be okay.

-removed starter and replaced one o-ring there, no difficulty here

oil filter cover - same paint as the engine
-little of fighting to get it off, but it came off with not much buggered head.  i call that lucky.  removed the oil filter, and the famous washer that like to go missing is still intact, i call that lucky #2!

oil pan cover - autozone changed out their paint inventory!  i have been using rustoleum brand and just happen to short a can of engine primer and cast coat iron!  had to get VHT brand instead and paint came out different, oh well, minor differences in color but i don't think it's much noticable as it will be on bottom of engine
- removed the bolt without much difficulties either.  pan dropped right down.  plenty of crud in the pan, but did not notice any metal specks, i call that lucky #3!


clutch cover - painted black.  i didn't want to use the VHT paint of slightly different tone than the engine, so i went with black, hopefully this will match with the cylinder and tappet covers

will put in oil and seal the engine tomorrow.  i already have new mobil 1 racing 4t 10w-40 on hand that i bought a while back, so i will use this instead of go out and buy different oil.    the engine is still far from getting fired up, and i just wanna make sure i have some oil in it while it sits.

[goldarrow]

Well, I'm buttoning up the rest of my engine covers  and everything was going along very well until I peep into the oil filter hole. Looks like something was eating the metal of bottom case right at the tip of oil filter bolt? 

Anyone ever seen this? Experience it? Please chime in.




And wait, is that a crack? Will my engine be ok to running like this?

[rb550four]

Looks like PO cranked the crap out of the oil filter bolt , stress crack... If I saw that at this stage... I would complete the engine and run it . Measure the size of the crack now, remeasure each oil change to see if it remained the same or not. Could run forever or break next week , fortunately it isn't a moving part and would not be subject to the pressures of most moving parts. I'd run it. Just remind yourself of it's condition while tightening the filter bolt. 
    Anyone else?

[Mcwilliams570]

Like rb500four said I would run it like it is (I am a cheap bastard) and keep a close eye on it.

Matt

[Stev-o]

Run it!