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let the games begin - R69s engine rebuild

Posted: Thu Mar 12, 2020 9:02 am
by malmac
Well after several years of working on other projects, The R69s is finally under the spanner.

As you all know working on the bikes is often made a lot more pleasant by having the right tool.

So here is tool number one that I built today. A piston pin pusher. Yes I could have bought one at the auto store for $10 but I like to make stuff.

So next step is to pop the engine out.

I see Jtaylor is also working on his R69s, so I will be checking out his thread as I poke along with my rebuild.


Mal
Australia


Suggest using some heat

Posted: Thu Mar 12, 2020 12:25 pm
by schrader7032
Suggest using some heat around the piston bosses to help the pin come out easier.

Thank you for the suggestion

Posted: Thu Mar 12, 2020 4:06 pm
by malmac
Kurt

Thank you for the suggestion.

The pins came out OK but the heat would have made it easier.

Thank you.


Mal

out with the clutch

Posted: Fri Mar 13, 2020 4:22 am
by malmac
Day two and the engine is out and the clutch is removed.

Also checked the big ends as an initial check.
I believe there is slight perceptable movement in the right big end and no obvious movement in the left bigend.
But it will need a rebuild for that right bigend anyway.

I have not measured up the pistons but I have new ones to go in anyway, so that part can wait.

Good to start this project and have not found anything unexpected at this point in the disassembly.


Mal

Day three, measuring the flywheel runout

Posted: Sat Mar 14, 2020 5:17 am
by malmac
I set up the magnetic dial gauge stand and dial gauge. Was happy with the result so I knocked up, well nearly got it finished, custom bracket to secure the dial gauge so it is 100% repeatable results. Runout was .06mm for face runout.
Dial gauge on right of pic below.
Finger gauge will measure the axial runout when it is set up.

Tomorrow I should be ready to measure the axial runout.

Mal


Some days are diamons, some days are stone

Posted: Sun Mar 15, 2020 6:33 pm
by malmac
Well the flywheel came off with enough pop to be be reassuring.
However it seems pretty obvious this is a flywheel which has spun in the past. Here is a couple of photos which show the way the flywheel had to be relieved on the front face (flywheel on left) and a second photo that shows how the crankshaft has less gap to the flywheel.

Well the really unpleasant news came when I put the puller on the front gear cover and it just fell off once the sealant on the gasket let go.
So the front nose bearing has been spinning in the gear cover......... mmmmm now there is a problem for a young man.

The pins in the breather plate dont seem to be lose, but I do have a new breather plate to fit.

So I suspect lots more surprises to come. So far Crank repair, front gear cover repair, rebore........ I can see the dollars adding up.

Mal


Pulling that front bearing from the crankshaft.

Posted: Sun Mar 22, 2020 1:28 am
by malmac
Well I wanted to be able to pull the bearing that sits at the front of the crankshaft without resorting to screwdrivers. Here is the new custom puller. Worked like a treat.

mmmmm well what is next?



Mal

after a lot of measuring

Posted: Thu Apr 02, 2020 1:49 am
by malmac
I had a lot of work sorting out which timing gears I would order.
Have decided to order the same as the crankcase is stamped with.

All the tools I have built to disassemble the engine worked flawlessly, so happy about that.

The crank came out today, what a drama.
The previous owner had tried to stop the rear bearing rotating on the rear journal by using some bearing mounting liquid (maybe loctite but maybe not).
The stresses are way to great and it failed.
However if he used the same liquid on the screws that hold on the oil slingers, well man that worked.
He had also used the countersunk screws with the hex for a 4mm allan key. Well tried the MAPP gas and those babies were not budging.
Eventually I destroyed the front oil slinger so I could get the crank out.
Then tried more mapp gas, but no go.
Eventually I braised the allan key into place and the concentrated heat from the TIG was really what sorted out the problem.
But because I had so badly stressed the screw heads I was obliged to braise the keys into place to get the critters out.

Experience.......

Mal

Building a crankshaft trueing stand

Posted: Sun Apr 05, 2020 3:05 pm
by malmac
Each time I work on the old bikes I try and add to our arsenal of special tools.

Today I started to build a crankshaft trueing stand.

Step one was machining off the base that will hold the arms etc. Lots of decisions to make as I want to build this out of materials I have on site. Partly because of the travel restrictions with the virus and partly for economic reasons.

I would be interested in seeing any of your designs as my design is still quite flexible.
For instance to use or not to use roller bearing at the top?????


Mal


so I have to wait for some stuff

Posted: Tue Apr 14, 2020 2:34 am
by malmac
So while I am waiting I decide to give my rear brake linkages a little TLC.

Will it make a difference, well probably not but it feels good to renovate things and breathe new life into old parts, rather than just throwing them away and replacing the parts with a reproduction part/s.

I think the picture pretty much say it all.


Mal