MZ/MuZ Riders

by **andyw** » Mon Apr 17, 2006 12:34 pm

Workning my way through the possibe causes of my 2002 Mastiff being a non starter now and need a little help on the carb front

Checked the basics, float bowl reasonable clean/free from debris, floats appear airtight, rubber diaphragm 'thingy' :oops:

appears free of holes/cracks (how can you be sure there's no pinholess?), nothing obvious loose/fallen off.

So, what's the recommended jet settings and which one is which? :oops:

by **Fil** » Mon Apr 17, 2006 4:07 pm

I had to strip and rebuild my carbs after they got gummed up from the bike being stored for a couple of years.

I basically striped out the jets and cleaned them, and made sure the float bowl and valve were all clean.

I then set the pilot jet/ air jet (whatever you prefer to call it) at 2.5 turns out as per the handbook, but some people say they will run upto 5.5 turns out.
Try this procedure to check the fuel level in the float bowl:
Replace float bowl drain pipe with a clear plastic tube of the same diameter (so you can see the fuel in the pipe).
Bend the clear tube up past the left side of the carbs, and zip-tie it up so that the top of the tube is well above the top of the carbs (making sure there are no kinks in the pipe).
Open the drain screw in the bottom of the float bowl, and the fuel should find a level in the clear plastic tube (make sure the bike is level too - not on the sidestand!).
The level you see in the clear tube should correspond to the fuel level in the float bowl. You can mark the level on the side of the float bowl and make any adjustments to suit.

Hope that helps!

Also, try a search on 'carbs' as I made a couple of posts relating to my carb problems a few months back - I think there were some set up tips that some of the guys gave me.

by **andyw** » Tue Apr 18, 2006 7:27 am

Appreciated Fil, really helpful

Anyone else, more tips advice?

by **andyw** » Tue Apr 18, 2006 8:50 am

Was going to foillow your tip for checking fuel level in the float bowl Fil but came across a slight snag! Previous owner was obviously ham fisted - drain screw head rounded right off, I still can't beleive I managed to get the SOB out.............

BSA Regal to the rescue.......they actually carry these in stock! :wink:

by **cat** » Fri Apr 21, 2006 3:06 am

andyw wrote:Was going to foillow your tip for checking fuel level in the float bowl Fil but came across a slight snag! Previous owner was obviously ham fisted - drain screw head rounded right off, I still can't beleive I managed to get the SOB out.............

BSA Regal to the rescue.......they actually carry these in stock!

ohhhh my...WORD!!! :shock:

I did that Wednesday night. (I had a bad night.) The frikking thing's made of lead! oh, you're lucky - mine's still in. :shock:

I tried different screwdriver bits but nothing seemed to fit properly. I think it was a bit graunched already from when I was replacing the float bowl screws, a while ago ...I must have tried it and found that it was graunching and left it.
So then I tried screw extractors. The little one was biting but then I made the mistake of trying to straighten it, align it, and it stopped biting. So I tried the next bigger one and it quickly just ...f**** up the screw more.

I was thinking I'll have to sharpen a small screwdriver and try to bash /chisel a slot in it. It's not easy to tap it out because it's down a hole, you can't get the screwdriver at the right angle.
I should have put Q10 on it so by tonight it would - maybe - help.
Why do they make carb screws out of lead - or whatever it bloody is! :!:

zinc or something.

hey, it looks like an air screw! What's it actually for? I was going to try to replace it with an Allen.
Oh well, maybe I'll getting hold of BSA Regal - if I can't replace it with an Allen. I want some sprocket lock washers and exhaust gaskets, and - another stupid thing - or stupid me - if you tighten the rear brake cable guide P-clips a bit too much ... they're screwed into brass "washer/nut thingies" that are held in the hole in the swingarm by the rubber grommet ... I ended up with the grommet inside the swingarm. I :cry:

was looking at what mx bike ones I could use instead.

by **cat** » Fri Apr 21, 2006 3:22 am

The images... you click the [img]button%20in%20the%20editor,%20paste%20the%20URL,%20then%20click%20the%20button%20again%20(which%20has%20changed%20to%20[Img*])%20...%20or%20else%20just%20type%20it%20[img]the_URL_in_here[/img]

andyw wrote:rubber diaphragm 'thingy' appears free of holes/cracks (how can you be sure there's no pinholess?),

Get a magnifier. From Kennedy. They're cheap, they do the job. Plastic. I just got one with some other Kennedy stuff. x4 magnification. It cost about..less than a pound.

by **cat** » Fri Apr 21, 2006 4:48 am

Andy, maybe you can sort this out for me. I'm trying to organise main jet drill sizes and so on - and if I'm going to order a float bowl drain screw, I want to get main jets at the same time.)

I've just found that 2 of the MZ Teikei diagrams I've got show different main jet arrangements - the secondary carb. One is the same as the Yamaha XT - it has what looks pretty much like a normal main jet but apparently held in by [#29 in the diagram - BOLT, HOLDING]. The other has what you could call a 'nipple' and seems to scew in itself without the 'BOLT, HOLDING'. I think that's probably the one we've got and the other diagram is the one is the XT one (a few slight differences) ....?

by **cat** » Fri Apr 21, 2006 5:03 am

Andy, maybe you can sort this out for me. I'm trying to organise main jet drill sizes and so on - and if I'm going to order a float bowl drain screw, I want to get main jets at the same time.)

I've just found that 2 of the MZ Teikei diagrams I've got show different main jet arrangements - the secondary carb. One is the same as the Yamaha XT - it has what looks pretty much like a normal main jet but apparently held in by [#29 in the diagram - BOLT, HOLDING]. The other has what you could call a 'nipple' and seems to scew in itself without the 'BOLT, HOLDING'. I think that's probably the one we've got and the other diagram is the one is the XT one (a few slight differences) ....?

Check the pictures...

by **andyw** » Sat Apr 22, 2006 12:16 pm

Cat....I have an XTZ660 ('91) manual and my carb setup is as shown in that (diagram attached) - apparently a Teiki Y26PV although apart from a 'TK' marking and 'Made in Japan' there are no identifiers on the carbs that I could see.

by **cat** » Sat Apr 22, 2006 5:03 pm

andyw wrote:Cat....I have an XTZ660 ('91) manual and my carb setup is as shown in that (diagram attached) - apparently a Teiki Y26PV although apart from a 'TK' marking and 'Made in Japan' there are no identifiers on the carbs that I could see.

Thanks.

That looks like a 3rd different configuration of secondary main jet, and they're all the Y26PV - although I think there is some other number involved along with that - I saw it somewhere. I wonder if that's the same main jet as the Baghira.

by **andyw** » Sun Apr 23, 2006 12:19 pm

Interesting, I wonder what 'variants' are in use on the MZ's?
Maybe bikes of differing age use different cab setups?

And Fil's idea on checking float bowl fuel level in action............

MZ/MuZ Riders

Carb cleaning / check-over

Carb cleaning / check-over

Re: Carb cleaning / check-over

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