It's 1979, it's purple, and it's Special

Uncertainty and doubt about flow-rate and demand exceeding supply made me re-instate the Special tank, which looks much better than it did, now it's got a fresh coat of black paint. I still don't like the shape of it, but it will do for now. Stripped, examined and re-built the vacuum taps and surprisingly they're perfectly fine now. The slight leakage they were showing was probably due to them sitting for years dried out.
Making haste slowly...
I had a can of spray adhesive in the mail, but it seems to have vanished somewhere in the postal system, so the seat re-building is on hold for now.
 
Fitted an AGM battery to the XS650 - since it has no starter motor, I reasoned a much smaller battery would be fine and since I fancied an AGM, I decided to try something out. I trial-fitted an alarm system battery of 7Ah, which might (or might not) live happily with the charging system of the bike. I wait to see how it pans out.

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DIY battery strap made of a 1" strip of 19" inner tube and 1/8" galvanised fence wire.
 
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I thought I'd not get out on it today, as the weather forecast was not good at all. It turned out to be erroneous (no surprise there, as the weather in Ireland can change very quickly, seeing as we're on the edge of one of the world's great weather factories). Anyway, decided to have a venture out.
After warming it up in the workshop and wheeling it out, as soon as I sat on it and took it onto the road, it felt for all the world like a 70s lightweight of small capacity - like a 250 Superdream or XS250. In fact, the low weight, narrow bars and better weight distribution than I'd been used to for years, kind of threw me and it took a good mile or so to get the feel of the bike. Once it had warmed up I started to give it some throttle.
It pulls like a freight train - any resemblance to a 250 went out of the window when the throttles opened up. The Mikuni VM34s fitted to it had made me wonder if any of the POs had done any internal engine work. Guess I won't know for sure until I ever have to pull the head. In the meantime, there's a few small things needing done but I'll have this on the road for the rest of the summer, at least.

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Made a start on a flip-over base for a topbox on the XS. Means I can ride it solo with a laden box immediately behind me, and if a pillion is on board, the box can be at the tail, like a normal one.
I'll finish it off and put a couple of pics up.
 
Fitted a Kwack / Nissin 14mm master cylinder, which gives me a nice span-adjust and dogleg lever, but there's a bit of lost motion in both calipers, which has only shown up since it's been on the road. When I rebuilt the calipers they were nice and solid, so I'll have to examine them closely and see where this motion is coming from.
 
Well, after a bit of running around the back roads, today I took it up the local by-pass and gave it a bit of welly. It reaches an indicated 80mph quite rapidly and seems happy enough sitting at that speed, but I suspect it's actually around 70mph. Need to check - 80mph indicated corresponded to 5000rpm, so I'll look at the sprockets and x-ref with others' posted figures for a corrected reading.
Still got a couple of niggling oil leaks, but I'll attend to them soon enough - clutch pushrod seal will be renewed when I delve into the heavy clutch action, and the bottom filter plate needs a couple of helicoils and a new gasket as a matter of course. The valve-adjust access panels could do with new o-rings, and one of them is weeping, also the cam oil seals are showing signs of age, which is to be expected. All this can be done as part of the shakedown - it was never a full-on strip and rebuild, just a get-it-going exercise.
Today was also the first shopping trip with it in its new guise of Pragmatic Ratter, with a topbox strapped to the nifty little platform, and I picked up some groceries and nuts 'n bolts to fasten the side panels on that will protect throw-over panniers from the springs.
When I got back to the house, the rear brake decided it didn't want to play any more and went away. Sodding thing - again, not entirely unexpected from ancient seals, and the rear brake was a bit of a forgotten item - it worked and seemed ok, so was left.
 
I use a less accurate, but easy to cognate, 1000 rpm's =15 mph.
So, 3000 rpm's is about 45 mph.
4000 rpm's is about 60 mph.
5000 rpm's would be close to 75 mph.

But, my tach is calibrated, and I don't care to do calculus while I'm riding...
 
... put some new pads in the fronts - cheapo Caltric, as I didn't want to spend too much if I was wrong - and the lost motion has largely disappeared, thanks to the presence of unworn and square pads now. There's still a bit, but I suspect that's caused by slight wear on the sliding pin and bush and possibly ancient rubber of the bush on both sides. I'll replace those in due course, but for now it's got two-finger stopping with the 14mm m/c and the lever is still a reasonable distance from the bar at full squeeze.
Moving on to the rear brake - I dismantled the rear caliper and found nothing out of order, everything was free to move, but when I laid the brake line down on a slope and cracked off the union at the top of the m/c body, a spurt of air came out.
I know where that came from - when I laid the bike on its side when I was doing the starter blanking plate. Oddly though, it didn't show up until a couple of hundred miles had passed.

The small brake bits and pieces - the anti-rattle and anti-squeal shims don't seem to be available outside of getting an OEM overhaul kit, so I'll have to stump up for a couple of those by the look of it. Since I'm planning to replace the Caltric pads with something decent, I'll buy OEM with the kit included - seems to be a fair price anyway.
 
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Once you get the rear brakes fixed you should be good to go. Nice job getting it going. Nice to have it ride able looks like fun is in your future. Nice countryside it the picture. :thumbsup:
 

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