Partially Restored 74 CB550

[davidcumbria]

All together with a pleasingly small ammont of hondabond external squidge. I  used a paintbrush to put it on as thinly as possible [ Guests cannot view attachments ]

[Oddjob]

Did you remember the spacer inside the starter gear as you inserted the shaft?

[davidcumbria]

I put the bearing spacer and thrust washer on the shaft as I pushed it through the starter gear. Tried the levering trick but couldn't really see enough through the oil pump aperture to do this effectively. In the end despite the new chain and rubbers I got lucky just by wiggling and pushing the primary shaft and it seemed to engage before some light malleting got it home. Does it look ok? [ Guests cannot view attachments ]

Going back  to our first discussion on this subject as you said Ken absolutely not necessary to heat the  rh bearing surround as in the high octane Matthew bochnack video I’ve bought. All this does is make more likely you’ll burn your hand and find the job more difficult.

[McCabe-Thiele (Ted)]

I'm almost  at the same point as you with my 500 cases - just checked the con rod cap nuts again to make sure they are properly Torqued up.
Next step for me is to clean the mating surfaces again with Meths  then get the Hondabond out. I too have new chain, primary drive rubbers and bearings.

TBH I will be pleased when I am at your stage with the primary drive shaft in place - you must be chuffed with how it has gone.👍👍👍

[davidcumbria]

Thanks Ted. It’s been a good day. my tips

Check and recheck bearing pins are properly located. One of mine got displaced after running through the gears before bolting cases together.

Put the crankshaft seals on before fitting to upper case

Use a fine paintbrush to lightly apply the Hondabond squeezed into cap. Less risk of overdoing the area round the bearing caps.

Don’t forget the casing dowels

Try wiggling and pushing the end of the primary shaft into the rh bearing. As soon as it catches light persuasion with a rubber mallet did the trick for me

Make sure surface is soft and contact surfaces of engine are protected. They’re a lot of turning this heavy lump over.

Good luck Ted.

[davidcumbria]

[ Guests cannot view attachments ]

[Bryanj]

Nice pic of the knackered primary chain.
The 550 is a slightly different casting where the main oil gallery is compared to 500, on 500 the chain can cut a big groove into the ally and, reportedly, has even worn through!

[McCabe-Thiele (Ted)]

Good point about having a soft surface for when the case is turned over etc - when I put the Hondabond on my 400 cases I wore disposable blue rubber type gloves - squeezed it out like toothpaste onto my left fore finger then dipped my finger into the worm cast then smeared it on with my right forefinger - it seemed to work for me. Not sure if I have the right sort of brush to get it on thin enough.
NJ gave me this tip - I had plenty of trials with my Groundhog phase.

[davidcumbria]

I’ve been busy assembling the front end to get the frame ready for the partially assembled engine. Here are some tips and experience to share. Old news to some but more info than I could find when searching.

A steering  head  bearing seems to have dematerialised between counting them out and counting them in soo had to order one from DS. Bet they were cheering when they got that order! Good tip about tightening the bearing by turning the steering head with spanner held in place so the bearings are rolling. Had to remove some of the powder coating so the top yoke would fit properly.

Had three progressively better attempts to fit the fork seals. First attempt rubbish when my too small socket damaged one of the seal springs trying to straighten tilted bearing. Majorly pissed off as I  had done this job ok loads of times before. Dug out some 1.5 inch abs pipe and with a bit it grinding it made a perfect sized drift which worked  ok on second attempt but more hammering than I would have preferred to get seal perfectly lined up below circlip groove. At least one was done and I could stop fuming. Final fork I heated the top with my heat gun and then was able to have a couple of attempts to get the seal started straight and fairly well in just with fingers. Couple of taps with old bearing on top and it was in straight in a jiffy. Old seal  is great drift because it’s easy to see the alignment between the top of the fork and the top of the old seal a few mm above it, not so  easy with a drift sticking up a couple of inches. It’s all about getting the final push started with the seal square and the heating and use of old seal as drift really helped with this.

Bought some lovely new fork tops and protected the chrome with tape. With the stanchion in a vice my first efforts to push down the spring and engage the threads were frustrating. Even engaged her indoors to stand on my work mate where the vice us mounted. Was running out of strength and really worried that pushing and turning so hard was going to risk thread damage. Finally on about the the tenth attempt it worked and I could leave the garage happy but determined to find an easier way for the other one.

 Searching found a post by K2 where he mentioned turning  backwards first to find the thread lead in point. I tried this but couldn’t detect it. Problem is you have very little capacity to turn much and maintain gorilla pressure on the socket T bar. Solution was to take out spring and fit the cap then mark with permanent marker stanchion and fork top so you can see where to position so both lead ins engage. Obviously would have been better to do this before filling with oil. Anyhow it worked and got the blessed thing started on next attempt. A triumph of thinking over brute force. I don’t do enough of the former and haven’t got much of the latter!

On to the swingarm which I’m now having to have re powder coated since my freebie foreigner job at local factory was obviously rushed and the finish is rubbish. Pay peanuts get monkeys !

[davidcumbria]

Bit of an update. New swingarm powder coating , bearings  and fitted. Forks rebuilt with new seals and front end fitted. Once bike on its wheels fitted the engine single-handed with pipe lagging to protect shiny frame.

Barrrell Bores checked out fine with bore micrometer with just 0.05mm of barrelling vs .12 mm max spec. So I was surprised that the ‘new’ rings I thought had been put in were out of spec on ring gap in the cylinder. Got a good deal on piston kit from imd pistons and now have shiny new pistons and ring gap bang within spec. Piston clips stayed out of the crankcase !

Do I need to hone the bores to bed in the new rings ? Would a rub down with emery paoer suffice ? What grade ?

On the same theme the ‘ new’ cam chain tensioner blade didn’t stand up to close examination and had fatigue cracks in it that ran to about 3/4 of the blade thickness. See photo. CMSNl have a new aftermarket replacement for £33 , third the price of oem.

So barrels on next when the blade arrives with some great tips already logged from Teds thread on how to fit the tensioners.( protective cover taken off engine for photo)

[davidcumbria]

Continuing my conversation with myself ( nothing new there 😊)  Valve lapping yesterday. I had splashed out £10 on one of those drill attachments that produce a side to side motion. Going by the reviews like others felt I had wasted my money because nothing would get the sucker to stay on the valve. Finally cut out some high strength Velcro and stuck it to valve and sucker and halleluha it worked. But even though I kept turning the device and restarting it still produced the dreaded ring scores that you are trying to avoid by using a drill conventionally. So my conclusion is useless !

Found my old lapping stick purchased in 1976 to do my mums mini at the bottom of a tool chest. That was satisfying. It struggled a bit too with suction on the small diameter exhaust valves ( I’ll forgive it after50 years ) but Velcro did the trick. Good to know there’s been some progress in ideas over 50 years.

Another new bit of kit used were the polishing discs/ brushes  recommended by Ken which did a great job removing the baked on combustion residues.

QUESTION - is there a correct orientation for the valve springs on a 550 in terms of the windings like there is apparently on a 400 ?

[McCabe-Thiele (Ted)]

On my 400 the inner springs iirc are clearly a sort of tapered coiled design. The springs on my 500 were completely symmetrical they might not be original though.

[davidcumbria]

Thanks Ted, yes my 550 springs look symmetrical so seems not an issue 👍

[davidcumbria]

So reading a few threads about starter clutch screws loosening I lost faith in my prior efforts to stake them and to avoid the niggling worry decided to redo them. This meant taking the engine out again ( not a problem since no block and only 3 mounts loosely in place). Reasonably straightforward to get the clutch out using this method.

http://forums.sohc4.net/index.php?topic=122084.0

Although I had used blue loctite it was imho still too easy to loosen them so I was gratified that this whole reversal hadn’t been a waste of time. New screws on order, decent staking tool obtained and red loctite at the ready. No need for these screws ever to come out again and ear worm dealt with !

[davidcumbria]

Health warning !

I found refitting the starter clutch very tricky with engine out and sump cover off upside down on the bench. Could not imagine how difficult this would be trying to work under the bike with engine in frame. Very hard to retrieve the small starter gear and correctly align it so the pin will go back in when access is so limited by the starter clutch and Mainshaft gears. Did manage eventually with help from missus as three hands needed. ( lift / wiggle starter clutch , retrieve/ manoeuvre starter  gear with long screwdriver, insert pin. ) key breakthrough was using a screwdriver in place of the pin to hold/ manoeuvre the starter gear into alignment before removing carefully and trying the pin. 2 hours of frustration but got there in the end.