Suzuki sells a plug for the cylinder head...  still available and not very expensive...  less than $3.  Part # 09247-14025

(The ones I bought a few years ago looked just like OEM Yamaha...  the pic on Partzilla looks a little different now.)

I used that Suzuki plug on my head . The Yamaha one is NLA .
Skydancer , send me your email and I'll send scans of the brochure .
I thought the 69 Range booklet had a pictorial shot of the bike .
It did , but was shot from above and in shade , so of next to no use for your purposes .

Swoop,

I sent you a message with e-mail,  thanks . I took a look at the Suzuki part number. Great price but i wonder what style plug you will get if you buy from Suzuki? I see both old and new styles on e-bay but of coarse they want big money for them there.
I see vintagemt1 has a Yamaha reproduction plug for $15.00 plus shipping. Nice looking but still rather expensive!

I'll see if I can take a photo of mine tomorrow . Hopefully I'm able to get a clear shot .

I found a blind plug for the head. I had one in my miscellaneous bolt box. I think i removed it from the RT3 i restored many years ago. Took the bike for a ride today. Runs great down the road. Has plenty of power, revs easy up thru 8 grand. Carburetor spot on.
However like i mentioned earlier it has some piston slap noise when revving it and letting off the gas. I took the cylinder off, To much clearance in the piston to cylinder and ring gaps are way out of specs. Surprise it runs as good as it does. Crank and rod are in perfect condition. Will need a cylinder bore and oversize piston set. To bad because the piston and cylinder look great but has to much wear! More money.

Black paint on the cylinder looks original but i highly doubt it. Doesn't look like this cylinder has ever been off? Still deciding what way to go on it. Bare metal vapor blasted or painted with polished edges. 

After using some paint stripper to remove the black paint off the cylinder i could easily see the original black paint under it. The paint stripper removed the rattle can paint right off but really wouldn't touch the factory black paint. So this cylinder was painted black with bare metal edges (not polished) when new.

That answers the question did the 69 DT1's come with painted cylinder's or bare metal cylinder's. At least i know this bike came with a painted cylinder. 

After sand blasting the factory black paint off the cylinder, I had it and the head plus the carburetor vapor blasted. Came out nice so i decided to leave it bare metal like the 68 DT1's. I think it looks better bare metal with the 68-69 painted lower engine cases.

Here is a link to the picture of it. 



  

Skydancer looks great in my opinion 

Little bit of a update on this 69 DT1.  Cleaning up pretty nice. Top end and left side of engine completed. New NOS Yamaha piston, rings, wrist pin, upper bearing, new gaskets. New points, engine timing set while head was off, timing pointer lined up, all new seals, new counter shaft sprocket, shifter re-chromed, new side cover gasket.

I went with a sealed battery on this bike. Made some wire connectors. Can resort back to STD battery quickly if needed. 

Front end is also done. New hard chrome on fork tubes, new K&L fork seals, Nos O-rings in outer nuts, Nos fork dust boots, new oil, new painted lowers. New front wheel bearings, new Yamaha brake shoes, new tire, tube and rubber rim protector.

Going with Duro Tires on this bike for the 1st time. Usually i use Heidenau's but after checking to see if Duro had the correct size tires and were DOT rated i decided to try them out. From what i see so far there a good looking tire. 4 ply directional tire and have a great tread pattern. Cost almost 1/2 what Heidenau cost.  I don't think this bike will be rode much so these should work well while keeping the price of the bike down. 

Still have a ways to go, Only thing slowing me down is the weather. Winter doesn't want to give up here in Michigan! I do most my cleaning and all my painting outdoors.








 

After 7 weeks and $3100 dollars later she's pretty much done and this was only a preservation, not a full restoration! That would have cost another $3000 dollars. I think it turn out nice especially since this bike will be a rider. Not going to be sitting in some ones collection. Only have 2 small things left to do and then i will put about 25 miles on it in the next month or so. Make sure nothing arises up before she is shipped out to it's new home out west. 

I must admit i think the 69 is the best looking DT1 badge bike between the 68 thru 71 models.. Just my opinion after owning all 4. 

Wow!
Incredible "preservation".