Teds new project a CB500 K1 mostly version 0.5 circa 1972.

[Bryanj]

The front, static, blade goes INSIDE the chain with the rib facing forwards.
If you dont you wont get the cam sprocket on.
I find it easier to fit the tensioner mechanism with the barrells not all the way down to make sure the bottom goes into the pocket its supposed to

[Oddjob]

Second that. Leave the barrels about 1" from the crankcase, fit the tensioner bolt through the barrels, don't fit the nut. As you drop the barrels watch to ensure the tensioner goes into the slot in the lower crankcase. When it does, fit the oring, the washer and the nut. Push in the tensioner blade all the way and then lock the nut off. Don't release it until the cams in place and setup correctly.

Same for the front guide, fit when the barrels are standing slightly proud of the cases. It has an arrow which faces up, also says UP IIRC and as Bryan points out it goes behind then chain so that the chain goes between the guide and the front of the barrels.

[McCabe-Thiele (Ted)]

Thanks for the pointers both of you:-

So the cam chain adjuster screw is on the rear of the engine,  the fixed blade being fitted so the chain is between it & the front of the block.

For the fixed blade I can see it has the word UP on it with a two pairs of arms  - I can see the side arms that sit in the engine casing recess at the bottom - so it sort of hangs from the slots in the top of the block until it fully engaged at the bottom - sounds fun.

[McCabe-Thiele (Ted)]

Block fitted today:-

Lower block gasket & O rings & restrictors  in place - the four larger block seals fitted to cylinder block - part lowered block to fit cam chain through tunnel.
Block fitted onto studs lowered down to a small wooden support block on rear edge of chain tunnel  - pistons fed into bores 2 & 3 then 1 & 4 with cam chain through tunnel - cam tensioner & guide fitted into place - adjuster locked back once block fully lower into place.

All feels good - plenty of exercise walking round the bike ramp whilst feeding piston rings into block.

[Johnny4428]

Making good progress Ted! Looking forward to some pics.

[Oddjob]

Check the tensioner has located in the slot in the lower crankcase, then check again just to be safe.

Should also have said to check the tensioner itself, after speaking to another member recently it's apparent a number of these tensioners are actually bent like a banana, caused by fitting the tensioner into the lower slot and then trying to fit the bolt through the barrels, doing it this way can bend the lower part of the tensioner as it's only pressed steel with little structural strength. This causes the blade to bend ever so slightly thus putting more pressure onto the chain than it should and if the chains new that means it's harder to get the chain onto the sprocket and the sprocket onto the cam.

I have 6 or 7 tensioners all restored and bagged, one showed signs of not being in the slot, the bottom edge gets chewed by the primary chain, 4 others showed bends in the lower half of the tensioner, when new the tensioner is straight, if yours looks bent it's because it is. Another way it could be bent is in how it's removed, you remove the nut etc and then try and remove the bolt from the barrels, this can do the damage in reverse. Always lift the barrels slightly before removing the tensioner, just to disengage the tensioner from the locating slot.

[McCabe-Thiele (Ted)]

Thanks Ken,
The long tensioner blade was nice & straight I positioned it vertical with a gap of around an inch at the bottom. Fitted the fixed guide so it was pivoting at the top - I could see the lower section engage in the recess. I knew the rear blade was in position at the bottom as it did not move sideways when block down- after locking the nut in place with the adjuster screw in the fully back position - top part looks nice & vertical.

[Oddjob]

Always pays to check Ted. Saves gaskets if nothing else 

[McCabe-Thiele (Ted)]

As well as the tips here I found the Honda Workshop manual in the download section a handy reminder.👍👍👍

[McCabe-Thiele (Ted)]

A little more progress all cling filmed up to keep out the dog hairs!


.PXL_20230726_134925498 by Macabe Thiele, on Flickr

[Sesman]

Coming on nicely, Ted.

I was wondering, did you get round to having the tank and panels painted?

[davidcumbria]

Getting there Ted. Forks look shiny ! Some of the bolts around the headstock and fork tops look comparatively less so. I have bought a couple of new fork tops from DS and will put an order in with Kay fasteners for some stainless nuts and bolts. Not expensive and I always think stuff around the instruments handlebars  and forks that you see when riding is the most satisfying to restore.

Going backwards today taking my swingarm in for a second go at powder coating….
After all that work on the engine best to keep dog hairs etc well away….

[McCabe-Thiele (Ted)]

Headstock bolts are stainless - I haven't buffed them before use.

[Oddjob]

Middletons are already polished Ted, cost a little more but none of that appalling writing on the surface of them.

I've also polished some stainless bolts not from Middletons and they look chromed if you do them right.

[McCabe-Thiele (Ted)]

Clutch unit now assembled and shimmed up behind the new SS circlip.
Now back to more polishing work on the clutch cover/ case just done a number of 30 minute sessions on the buffing wheel in the last couple of days using  coarse then medium soap.

Keeping the deep scuff marks for now just aiming for a nice shiny overall finish when I move to the fine & very fine soap over the weekend - trying to do stuff whilst Wendy is at work during the middle of the day in her new part time summer job.