MZ 250 causing no end of greif

[Blurredman]

Right, well I purchased and tested out a BR7HIX Iridium spark plug by NGK, and I can conclude that it made not a jott of difference to any performance, other than maybe a more responsive top range?

The bike's acted slightly boggy of late when pulling away from lights or anything from a stop, It idles fine, and naturally gives a great turn of speed when giving it a good race on faster roads.


I will put the battery on charge for a long time now and see what difference that makes, I hear that the MZ can be tempermental with a battery not in tip top form giving a somewhat innadequate spark. In some ways, that's why the Honda CG125 I had was so great, Magneto ignitions can look after themselves.

[Skorpion]

Right, well I purchased and tested out a BR7HIX Iridium spark plug by NGK, and I can conclude that it made not a jott of difference to any performance, other than maybe a more responsive top range?

The bike's acted slightly boggy of late when pulling away from lights or anything from a stop, It idles fine, and naturally gives a great turn of speed when giving it a good race on faster roads.


I will put the battery on charge for a long time now and see what difference that makes, I hear that the MZ can be tempermental with a battery not in tip top form giving a somewhat innadequate spark. In some ways, that's why the Honda CG125 I had was so great, Magneto ignitions can look after themselves.

If by bogging you mean you are having to give it more throttle than usual to set off, this could be down to the cold weather, try the air screw one turn out, if no improvement lift the throttle needle one notch.

[Blurredman]

Okay, done that. It did respond better after I put the needle up a notch (now on 4th from top), I didn't know whether it'd work because even when I was bogging down, pulling the throttle back didn't seem to do much.


However, It's still tempermental, I don't think it helps that I broke the cable adjuster on the carburettor for the choke. I can't seem to find said part available on the internet or otherwise either, any links to the choke cable adjuster?


However, looking at the milometre, it looks to be the best MPG i've ever had.

[mark h]

Have you tried phil speakman at themzshop.com??

[Blurredman]

Okay, so it seems that the bike isn't effected by the broken adjuster, but I still need to get one in the mean time.

I did put the needle up a notch, and it was better I could tell.


In other news, since I was in reserve, I decided it was a great time to do these things:


- Drain all remaining fuel from the tank, to check for water. No signs of water, although a lovely orange colour petrol from the 2t mix .
- Take fuel tap off
- Generally cleaned the tap, realising for the first time that there is a two phase filtering system, which worked well I could tell by the lack of anything floating in the drained fuel.
- Tried to clean the filters on the tap as best I could.
- Put fuel back in,
- Decided to go for a ride and fill up.

I'd already noticed many times that the bottom of the tank has alot of rust particles sitting about, I was going to splice into the fuel line to the carburettor a fuel filter, but after realising the two phase system on the tank, and the fact that, all the way through reserve I got no particles of rust at all, I felt having essentially a 3rd filter was just pointless.

Either way, rode to petrol station after putting it all back together and rode back and it was a much happier bike. Oddly, I had to decrease the idle screw by quite a bit. As the bike warmed up, the idle increased, and I brought it back down with the screw, it does sound a little less 'dieselly?' and a bit more fruity like I expect a 2t should. I think, but I'm not sure, that the idle has increased because there is a much better flow of fuel now? I got 62.2 MPG according to fuelly, and managed to eek 201 Miles (but not before reserve).

Fuelly:
http://www.fuelly.com/driver/blurredman/etz-250

Which is my best ever on this bike. I just hope it keeps this good running going, I plan to use it for work on Monday, and I don't want to find, like alot of occasions that it feels different then say a day before.

[therealche]

Glad to hear you are getting your Z running right! That fuel consumption is a lot better than Ive ever seen, mind you I do thrash the b........ its of mine .

[Blurredman]

The good fuel consumption (if I ignore the absolute terrible ones) is quite suprising really considering how bad the piston and barrel condition are. They are scored badly, and I never even checked the rings to see how bad they were

One day I'll buy a new piston set and re-bore the barrel. As cheap as a piston is, I've spent an absurd amount on this bike already really, and now that I think it's running fine, I'm not going to touch any of it other than to ride it.

[Blurredman]

By the way, I thought it only fair that I post an image or two of my bike.
I'm not a fan of the paintjob, though it seems most other people are . In the summer, I hope it'll be nice enough to give it a proper strip down, hammerite the frame, sort various issues I have (no rear wheel brake switch atm), and paint the main body Orange, and put the appropriate decals on and give it a tart up on bits other than the body (like the brake caliper, wheels, handlebar controls). I'm actually it's 3rd owner (however 2nd owner had it for only 2-3 months before I).

I've put a fair bit of money into it even if it doesn't look like it.
Exhaust is new, that side stand was pretty expensive (although they all seem to go for 20-30 quid), proper etz250 side panels bought in readiness for summer paint, keys and locks, clocks, rubbers, kickstart, new clutch plates and clutch springs, seat, Need to sort out proper connections between bulbs and their beds, as well as a fair bit of crimping. Bought a lot of cables since i've bought it (mainly just to stock up). I also have a new chain and rear sprocket/hub thing to go on it sometime.

It's still running on pre-mix of 30:1, and i'm still getting good MPG figures and it's performance is now quite consistent. It still has the Dunlop D803 rear tyre on it, which I put on it when I first got it, in order to use as an offroader, it's almost got no tread left on it now, so i'll switch it for the other D803, and use the tread on that too (I'd only be throwing them away otherwise), then put the road tyre it did have on it before I switched it.

By the way, anyone else in South Wales??


This is what it looked like when I first got it in October.



This is what it looked like after an offroading session:





And these are recent pictures (today infact) of it. I no longer offroad it.

[therealche]

Fine work in progress, money never shows until the last minute. If youve still got the old exhaust I'm sure there's a few people who would take it off your hands and help pay for your paint!

[DAVID THOMPSON]

keep working on it ...
over here i have not seen a STREET 2 stroke in actual use as a daily driver
in several years
out in the country the 2 stroke dual sports are common with plates
so they can use a road when the trail runs out

once in a while you will see some one using one for a few days when his car is in the repair shop
its all most always an older dual sport
dave

ps when you get it nice get a big chain so some one does not nick it

[Blurredman]

Right, so after a few months I have been doing alot of work on the MZ..

I stripped it down, repainted the frame with hammerite, and cleaned up the wheels, put road tyres on, repainted the front and rear mudguard (filled in the hole that is in the front mudguards on these bikes (why is it there?)), as well as the side panels and tank. I had to fill in some dents in the tank too and re-construct the centre line going down it, it seems to have collapsed over time or someone pushing down it.

Also did some welding on it, the yoke was actually touching the tank if i put it full right lock, and looking at it, i could tell the left side of the stop on the frame had already been welded. Just one of those things that wear down.
Also welded the holes at the back of the swingarm where the chain adjusters hold against. It appears that when I accidently put GL5 oil in the gearbox, when I left it a while and started up the bike and put it in gear, the clutch plates were so solid against eachother that the chain pulled so tight as to twist the rear spindle and the adjuster to go through the adjuster hole stay. So since then i've put a bolt there for the adjuster to hold against. Now i've finally welded the holes up and ground them to a nice flat finish equal to eachother and the ends of the swingarm.

Anyway, it's not the best picture but here it is..

The tank has been 2k lacquered, and is still actually curing, so the seat is only placed there for show. It hink it looks great, and i took inspiration from other MZ ETZ 250's which also had this colour scheme..