[Grand Designs] project - my ETZ 250

[Puffs]

Following a biased and flawed moderator choice (someone posting aggressive personal attacks is rewarded, while my technical posts are removed - behind my back & without any justification!), I have withdrawn from this forum.

[parrbd]

These switches can be difficult to set. I usually do it once a year before rego.

[dirtsurfer]

IIRC the piston came from the Hungarian supplier

These switches can be difficult to set. I usually do it once a year before rego.

I look forward to that when I finally get the wheel components fitting together.

I put the wheel together without the stand so I could move it
.. and put the engine in place


Strange granules in the airbox

[Puffs]

Following a biased and flawed moderator choice (someone posting aggressive personal attacks is rewarded, while my technical posts are removed - behind my back & without any justification!), I have withdrawn from this forum.

[Guesi]

I normally try to keep an engine light to ease hanging it into the frame, but heavy works too. And that looks like a Vape rotor.

Out of interest: did you do a re-bore? What piston did you choose?
Currently I'm having mine rebored and I went for a 70.95mm Almot with 0.05 - 0.06mm clearance. Time will tell if that's a good choice.

Yep , Bruce also warned me about keeping it light for remounting. The frame is still tucked away in a hard to get at space in my garage until I can reassemble the rear wheel and move it to a postion where I have room to mount the engine.

I went 69.5 which I think is 1st oversize.

I purchased the power dynamo VAPE as my generator /ignition system was buggered.

Next piece of the puzzle:

All of this was missing when I got the bike


Im guessing that the activator goes together something like this
.....

About the brake light switch: I think there is a small isolation plastic disk missing outside the brake shoe holder...It isolates the gold-coloured contact that goes inside the brake from earth(-) .

I mean this part:
https://www.guesi-motorradteile.de/inde ... 3/c/_/_/?_

[Blurredman]

I'm excited for you! Not long before you test it?


As for the rear brake switch. A lot of people just wired in a typical two wire plunger that is on every bike since what, the 70's? They typically can't adjust them because they don't know how to do it properly, or it is genuinely broken.

Either way- On my 250, I set it up once... 5 years ago... I've only adjusted it once since and that was because I changed the biting point of the brake.

How did you figure out the rear wheel space problem?

[dirtsurfer]

.....


About the brake light switch: I think there is a small isolation plastic disk missing outside the brake shoe holder...It isolates the gold-coloured contact that goes inside the brake from earth(-) .

I mean this part:
https://www.guesi-motorradteile.de/inde ... 3/c/_/_/?_

Its not obvious in my picture because its white plastic, but I did fit that part

[parrbd]

I think that washer is leather on my ETZ.

[dirtsurfer]

Still no idea what is going on with the back wheel. I trimmed a few mm off the spacer and fitted the assembled rear wheel into the swingarm whith the rear spindle tight in the sprocket hub I have a few extra mm on the brake side


In an effort to temporarily ignore this problem for a while, I focused my energy on wiring up the VAPE .
It makes a lot of this stuff redundant

[Blurredman]

Don't throw that stuff out though. Someone like me like to buy that stuff!

For example- i find that the mechanical regulators tend to charge slightly higher. Which is handy when you're in the city with lights and indicators..

The adjustment of the mechanical regulators is very handy! Also- I tend to find that my electronic regulator does not start charging with the lights on until almost 2k rpm (but with lights off 1500).. The mechanical regulator seems to better that result, with adjustment.

Anyway- Hope your ignition installation goes smoothly. At least smoother than your rear wheel- all I can suggest is one of the bearings in the sprocket hub isn't fully pressed in??

[dirtsurfer]

Anyway- Hope your ignition installation goes smoothly. At least smoother than your rear wheel- all I can suggest is one of the bearings in the sprocket hub isn't fully pressed in??

I reacquainted myself with the problem this evening
sprocket hub in situ with speedo drive removed to check if it was interfering, but even so stub axel seems a bit short?


sprocket hub as I have assembled it

[liquidgold]

Just been out into my garage to measure my ES250/2. Yes I know it is a totally different model but still an MZ and I wouldn't mind betting its all the same. Anyway it measures 17mm. John

[Blurredman]

I suppose you're only option is to buy another hub sprocket (thing)? It's obviously never going to fit in the swingarm, unless you grind down the swingarm to fit, and I don't recommend that!

Perhaps it is from a different model. Of course, now you're going to need to put a few mm of spacers on the spacer to counteract that, I suppose.

[Puffs]

Not so sure. That sprocket carrier is expensive, and I'm not sure something's actually wrong with that. The way your stub sticks into the swingarm doesn't look overly problematic. True, it could enter maybe 1 or 2 mm more, but not much more than that.

If everything works well, if all your bearings are properly seated, and if you chain is aligned properly, maybe just use a shorter LH spacer?

But of course the nagging voice remains: if it doesn't fit, something's wrong...

[dirtsurfer]

Well, I'm back to report that while I'm not ecstatic with the result so far, I have all the components of the rear wheel assembly fitted between the swingarm shafts.



There were a number of parts missing from the rear wheel wen I purchased the little ETZ, So I have replaced the entire rear brake , the cush drive, axel, chain adjusters sprocket cover and wheel bearings. I have had a little bit of time in the last week to examine my parts I found that:

• the internal collar on the brake backing plate was making contact with the wheel bearing
• The inner races on the wheel bearings which I had fitted were a little proud on one side
• The side stand I had purchased is a non genuine part and was a remarkably poor fit

So I

• filed down the collar on the bake hub so it no longer contacts the wheel bearing
• trimmed the axel spacer slightly to allow for bearings
• fitted the bearings proud side facing in
• Ground down the side stand until it fitted correctly

I still have a couple of mil spare when I tighten the axel but I can remedy that with a washer