Save and salvage, or humanely put down... TBD

[VinceNStuff]

Good day all. I've either rescued or slightly prolonged the suffering of a 1981 R65 currently sitting in my garage. Going to go over what I know and hopefully get an idea if this one is (reasonably) salvageable 

BLUF, I have time and tools and a garage and money, but don't want to waste much more than time. Can a good gasket kit and forks+shocks+brake bits+tires save this bike?

55k on the odo, but likely parked since '91. Scope in the spark plug bores showed some carbon but no scoring or discoloration. Leak down test was great somehow so it may have got rings at some point. Clutch engaged well enough to turn it over with the rear wheel and the starter actually does good as well. No noise from the shaft in neutral and every gear engages. I want to drop the sump and see if the con rods have any play, though not sure if that's telling for this engine. No corrosion visible through the dipstick or timing openings and there was somehow enough oil to still reach the dipstick. Oil drained clean so no obvious bearing damage yet.

Whatever was in the tank is of course rancid, though it came out without any flakes and the red coating is solid. Only superficial rust on the bottom of gas cap that I can see. Will likely strip and etch the tank. Petcock even moved smoothly but will need seals like everything else.

Haven't pulled the carb bowls yet but assuming they're bad. Both carb slides are free but a bit stiff...

Forks are pitted so would need new. Rear shocks are just ugly, aftermarket, and the only really rusty thing on the bike. No brake fluid left so the master cylinder is likely pitted as well and I'm planning on replacing everything north of the calipers. Dual calipers in unknown shape but they aren't dragging and I was able to push one in. Fingers crossed.

Weeping from the oil pressure switch and gear oil from the shifter bushing. Should I expect to have to split the transmission and case or can they get seals once separated?

Not looking for showroom or cafe butcher... just to keep on old bike running a few more years. My daily bike is an F800GT, so this one, if salvageable, would basically replace the SR400 Sunday rambler I let go.

Sorry for being so long winded, just looking for an honest take on this tired old steed.

Cheers,
Vince

[Tony Smith]

I would take it on. It is all there, just suffering neglect and the most expensive thing, cosmetics, are sort of OK.

I would drop the sump, the oil tends to come out clean when it has sat for a decade, it is what it leaves behind that is the problem.

After the oil change I would to valve lash which segues nicely into pulling the plugs and after refilling the oilturning it over on the starter to check oil feed to the rockers - you should have a good puddle in less than 10secs.

If you have oil pressure the next step is to pop the carb bases off. Red "dust" inside is good as that indicates last run on leaded petrol. Horrid green goo, you are cleaning carbs before fist start.

The reason I would go this way is to do the work needed to safely start the engine, as it warms up ghastly noises, oil leaks etc. You know the drill.

Best of luck.

[Bob_Roller]

The '81 model year bikes were known for early valve recession .
I have an '81 and needed a top end overhaul, valves and seats at 44,000 miles .
Without removing the cylinder heads, the only way to inspect the exhaust valves, is to remove the exhaust system .
Which brings on having to cut the finned exhaust nuts to remove them, if they have never been removed before and anti-seize compound applied, they are most likely seized onto the threads on the cylinder head .
The threads on the head are softer than the exhaust nut, usually they get damaged upon trying to remove the nuts .

[VinceNStuff]

Thanks all, good to know. I've torn deep into a few Japanese bikes but nothing this agricultural. I'll have to find some videos to get familiar with "normal" running sounds. Will pull the sump and get the carbs into the ultrasonic cleaner for now.

[VinceNStuff]

The '81 model year bikes were known for early valve recession.

Read up on that a bit, I'll see if I can get my scope bent over enough to look at that valve. Are the valve seats a press fit or a fiddly heat/dry ice affair? Valve clearance was plenty loose and the leak down+compression were good so I'll pocket that for down the road. I don't have an exhaust nut wrench but will need to invest in one eventually...

I'm hoping there nothing too scary on the crank, will try to come back with pictures soon.

[dogshome]

Hiya, story of my bike. Mine was a bit cleaner, but basically the same things to do.

* Shifter oil seal easy by removing the shifter shaft. Nothing falls off, goes out of alignmrnt etc. This is a standard metric seal (like most on the bike) and can be had for pennies. polish the shft where the old seal made a mark on it.
* Gearbox oils switch fiddly to get to, it will be the switch itself leaking not the seal I expect. They are not too expensive. Be very careful tightening it.

* My brake pipes were OK, but I replaced all the seals and the pipes. Dragging calipers due to old and gunked caliper seals is a thing. This can add up. So if pipes are good, leave them.
* Valves perfect on mine, bores within wear limits and good compression. Wear limits are very low being a plated bore and you will not see the wear like you would with an old Austin Mini or similar Iron bores.
* FD inner seal can leak, but is a standard size and easy to fit. Other seals and bearings in there more difficult. Any noise from that unit probably means it's shot. Not just bearings. Brake pivot leaks onto shoes, get next size up O rings and 4 ring shaft if you only have 2 ring. Easy fix.
* Fork seals easy and reasonably priced. Fork legs not cheap in the UK, either knockoff or replating the originals.
* Wheel bearings seals etc all cheap and reasonaby easy to do.

Would i get back what I've put in? (ignoring 860 upgrade) proobably not, but I have a bike that will last for several years like my lawn mower!


P.S. Why do you think crank may be bad? This part seems to be very well built

[VinceNStuff]

Hey, thanks for all the info. Shifter seal will be here tomorrow and I got a full engine gasket kit already. Not seeing any other leaks but will get it running first then see what needs attention.

I don't really know how the crank is, just worried about why this bike was parked. 55k in maybe 10 years (based on the non op registration) makes it look well loved so I'm optimistic.

The only known loss right now is the pitted forks (and 1980s tires n brake lines). Hadn't considered replating the forks, will shop around. Still need to get a look in that master cylinder.

[VinceNStuff]

Sidebar: the carb bowls are pretty tidy inside, plenty of good signs so far.

[dogshome]

No tears and goodbye just yet then 

[VinceNStuff]

Finally a little time for progress, dropped the sump in very happy with the condition of everything. Valve check showed slightly tight left exhaust but otherwise great. Current issue before I proceed is no oil flow for the right exhaust rocker... Topped up with some fresh oil and the other three rockers started dripping oil within 15 seconds of cranking. 30 seconds later and barely any weeping on the right exhaust rocker... It is getting a little oil but not not even enough to start dripping. Only difference I can see is that the rocker clamps that the cylinder head bolts go through have the notch facing outward. All other rocker clamps have the notches facing inward.

My (1984) Haynes manual shows the clamp notches facing outward but I'm not sure if that's a possible cause or not.

Any info on that one is greatly appreciated.

Will button it up for tonight, but hope to have the carbs sorted tomorrow... More to come as I find a free moment.

[Bob_Roller]

The rocker arm shafts have a drilled passageway for oil to flow from the cylinder studs through the rocker arm assembly .
I believe they only work one way .
Been a long time since I've had them off ,
You may want to compare a functioning rocker arm assembly, to the one that appears not to be flowing much oil .

[VinceNStuff]

Took some time to read up and the rocker shaft on this side is installed upside-down... There should be a dimple on top to indicate correct orientation and this side is on the bottom.

Not ready to refresh the cylinder to block or the head gaskets yet so just going to flip this rocker and get it flowing.

Baby steps...

[georgesgiralt]

I think you have found the reason while there is oil starvation. While you remove the axe, check the needles bearing and the state of the axe itself. I found that two of them where more than pitted.
Beware because you have opened a big can of worms. You know how and when you started. When will you finish ?

[VinceNStuff]

I lucked out and the shaft, needles and their cages were smooth. Reinstalled per a guide I found (not the Haynes manual) and all 4 rockers are now getting plenty of oil. As an aside, the oil that initially bubbled out that passage was so dark...

Carbs came apart one at a time and went into the ultrasonic bath. Only the idle jets were crusty but they opened up well with a soak and some untwisted copper wire.  Everything went together easy but tuning will take a few tries up here at 4500 ft vs it's original LA home.