Z1 as a project?

[AshimotoK0]

Is that in thou " Dave ?  ...3 thou" sounds a lot to me ... but that's with Honda spec's

[royhall]

That sounds about right for clearance. They are big pistons Ash.

[Bryanj]

Kawa rebored a lot of z1000 under warantee because people ran them in too slowly, dont run it in at all they said just use it as a normal bike but dont go racing. Tesco 15w40 DIESEL oil(might be 10w40)

[MrDavo]

Just back from picking the barrels up, I nipped into Tescos and bought 4l of their mineral 15-40 for £20, cheers Bryan.

[Bryanj]

Was diesel ?

[MrDavo]

The motor is mostly back together now, with new rings and valve seals, plus a light hone. Hoere's a photo I took yesterday of the cams being timed. I've never done this before on a Kawasaki, but following instructions on the Z1 forum it was straightforward enough. Note the paint dots on the cam sprockets and chain, at zero and 28 links.



Despite keeping all the parts for each cylinder separate, and not regrinding all the valve seats (i'd only done 375 miles), a couple of my valve clearances are right up the pictures, much to my disappointment. Two are under, (practically zero) two are on the big side at .15mm, so I'll try swapping the shims around.

I dont know how that happened, if you put all the same parts back where they came from everything should be exactly the same. But they aren't, and we are where we are. Luckily there is an excellent guide to valve clearance setting on the Z1OC forum, I've ordered a genuine shim tool and, following advice on that thread, one of the smallest thickness shims, so I have a spare when swapping around the shims, and a way of remeasuring the two with virtually no clearance.

[royhall]

After rebuilding the top end of my GS1000 which is virtually identical to the Z1, I shimmed it spot on but 300 miles later it was all over the place. Apparently this is normal behaviour and it settles down after the run in period. Bloody site easier with some nice Honda tappets.

[MrDavo]

jumping back a stage, but I had to dig out this photo last night, as I was worried that I hadn't considered which way up the head gasket should be. as it happens you can see I did do it right. You can also see the hatching from the light hone the engineering shop applied to my glazed bores. I'm now using Tescos mineral oil for running in, last night as I poured it in the smell brought back memories, mainly of being covered in the stuff.....



I got a 2.0 shim from Z Power., so I could measure the clearance on the two valves with zero clearance, and to give me an extra to do some swapping around between the tight ones and the wide. I also got the genuine tool to make life easier. I had to buy a single 230 shim to get one in spec, they are finally all within the .05 to .15 (as modified from 0.10 in a service bulletin which I've read about but not actually seen) range now, so happy days, exhaust pipes and cam cover are back on. I'm at the Silverstone Classic this weekend, but next week I only have to assemble and readjust the carbs and I can have another go at running her in.

[sprinta]

If you are a member of the Z1 OC they do a free shim exchange service just for the cost of the return postage.

[K2-K6]

Hopefully you've got all the elements of concern in this reset that'll allow a good bed in process.

You'd expect the valve clearance to change during that period but with a more accurate and consistent read on where they are after 500 miles or so.

Newly cross honed bores will be helped most to bring the rings in under higher torque loading,  rpm is restricted to control the lapping linear speed (it's just machine lapping really) while the bore has it's "teeth" in place to cut the rings effectively.

[Bryanj]

Big thing is do not baby it or you will glaze the bores and then burn oil

[MrDavo]

Back on the road this weekend after her little reset, with a sump full of Tescos mineral oil and definitely no 3k rev limit this time round.

I got the wife out to watch it start straight away and ..... nothing! Quick fuel and spark check - sparks yes, so I dropped a float bowl drain plug, and.... nothing!

It turns out that although there was a little petrol in the tank, the head wasn't enough to open the float valves. Jump in car with a petrol container, and put 5 litres of Super Unleaded (Because E5) in. Retry, instant start! A bit reluctant to go on all four pots, I may have fouled a plug with the oil I squirted into the bores when I assembled the top end. Anyway, a pop and a bang an suddenly its running clean and off the choke, so grabbed my helmet and went for a 13 mile test, before the heavens opened again, I got back just in time.

No smoke, running clean and the plugs looked Ok. Its a lot easier to ride now I'm not watching the tacho like a hawk - not thrashing it but riding normally, as recommended by the engineer that measured my bore clearance, as well as people on here.

After leaving her overnight to cool down, the oil was at its normal level, and I recheked the torque on the head bolts. Outers and inners didn't move, the pairs between pots 1 and 2, and on the other side between 3 and 4, all took about 1/3 of a turn. Some dry weather to get some miles done would be a help, she's still too shiny to take out on a filthy day, not a good state of affairs I know, but better than my mate's idea that I should buy a van to take it around in, like he does with his show bikes. ! I'd rather sell it than do that.

[Bryanj]

As well as not babying try not to do short trips, nice and warm plus miles

[MrDavo]

Just back from a 50 mile ride out, yesterday I did 70 miles going to Three Sisters circuit and back for a spot of karting with a few of my mates. Here's the bike at the top of Holme Moss admiring the view.



Basically, the bike is running perfectly, very smooth, mechanically quiet, nice tickover etc, until it isn't!    Once on each ride, while running at speed, I suddenly lose a lot of power, but it doesn't cut out altogether. I suspect its running on two cylinders, certainly not four. Limping along, yesterday to get off the motorway, today to get off Saddleworth Moor, the missing pots slowly come back, until it all runs normally again. Then it's as if it never happened.

I haven't investigated yet, but my theories are:

!) Overheating, due to the engine still being tight, though I don't see why that would be sudden, I'd expect it to start running rough long before the sudden loss of power

2) Loose connection somewhere between coils and points or coils and power. That would lose two pots at once, but again I don't see how it would fix itself, electrics usually work or they don't. alternatively it could be a bad coil, that gets hot and gives up for a while until it cools.

3) Fuel. It acts as if its going onto reserve, as the power loss is sudden. There could be crud in there but the filters in the tap are clear. Alternatively possibly the cheap pattern fuel tap doesn't have a fantastic flow rate, maybe it's enough, or maybe it gets overwhelmed and the fuel levels in the float chambers drop until it won't run right. That could possibly fix itself as I go slow on low power, until the bowls fill up again enough to run normally. I don't want a Pingle tap as they look wrong and cost the earth, but I'd try it if I could rule out 1) and 2).

I'd be interested if anyone has informed comment on my problem.

[K2-K6]

Similar thoughts to your own about electrics,  not impossible but usually more definite if on off intermittently.

The fuel starvation view. Years ago looked at a friend's mother's Hilman Hunter that would run all day at constant 45 mph but anything significantly over as a constant it would gradually run into missing then slowing further until limping,  apon which state it would slowly recover.  Took ages to find but was a fuel tank that had internal painting coming away in long thin pieces that had been pulled into the feed line making a long slow restriction.

These will run about 3 to 5 miles on float bowl alone at gentle around town pace so would take a while to deplete before that buffer would show in running. It's certainly a possibility the tap may not have sufficient flow to give these symptoms. 

If you just rode at 30 mph would you see the problem?