MZ/MuZ Riders

My 96 Skorpion has been stored for a while by myself and the previous owner. The previous owner claimed that he rode it once, and at that time, he had to feather the throttle constantly to prevent stalling. I've never seen it run, except for the short bit it did with ether, and it might have been teen seconds or so. I've done a thorough once over on the carb. The choke cable and choke both concern me, as the plunger hesitated when I first attached it to the carb, and after a second attempt, it seems better but not 100%. Exhaust smells like gas, when attempting to start, but it's bit overwhelming. I apologize if this duplicates an existing topic. I could not find the same symptoms discussed elsewhere.

If there is a lot of play in the cable before resistance is felt on the choke knob there's a good chance the plunger is sticking. The seal on the plunger sounds like it has swollen. You could try sitting the seal in carb cleaner for a few hours, then a smear of oil on the ring before trying to install it again.

I'll try that asap.

Sweetness! I should have toyed with the choke sooner. The bike starts and idles now. Now I need to decide whether or not to remove and clean the carb again, or if I should start making adjustments. At full choke it idles a bit above 2k, and if I back it off 3/4 it will idle around 800. If I back the choke off fully, it stalls. Regardless of choke position, I cannot rev the engine or even bring the rpms up slowly. The bike has been parked for over a year.

not sure of idle on these but 800 is way tooo slow
dave
its not a thumper its a short stroke motor see what it does at 1200 or a bit higher

yamaha book for szr same engine says
1250-1350 U/MIN =rpm

Maybe I had it near 1k. However, is there a page here with carb tuning tips for the 660?

Your idle jet is plugged. Save yourself the headache and just go ahead and pull the carb and clean everything. Then, always shut the fuel off when the bike is going to sit, and drain the float bowl over the winter.

you might be able to remove the float bowl and get to the idle jet w/o pulling the carb, but I don't think so...

Sam

Thanks, Sam. Will do. Twisty Tie wires work almost as well as welding wire for cleaning those passages, btw. Will report findings. Do skorpions have any factory fuel filters? Does anyone use one? I doubt it would need it as much as a bike with a metal tank.

there is a filter in the carb its under the float needle seat as the fuel comes in from the tank
be careful removing the pin that holds the float the hangers break off the carb if you drive the pin the wrong way
dave

Oh, yeahhh. I remember dealing with that pin a long while ago. Do you remember if it had an arrow, and if so, does it indicate removal or insertion?

i think its tapered measure it with a set of mikes its hard to see
dave

FOUND THIS LINK when you get there go to top of link pages
viewtopic.php?f=20&t=4191&p=41680&hilit=pin#p41680

i work on so many different things its easy to get confused

yesterday's special project was a hallicrafters S41G radio made before i was born
new tubes and caps in power supply
thursday is oil change on the KING MIDGET engine
today's was a half delta loop antenna for 40 meters short wave band

So, with the fuel turned off, and no stabilizer added, the carbs got nasty in a year and a half, but the fuel in the tank was still useable(I know, I know). With the choke issue resolved, all she needed was a second carb cleaning(the first one being done by me when I first aquired the bike). After the carb was cleaned, I fired it it up and rode it for the first time. I was elated! Will wait to fine tune until a fresh tank is filled up, VERY SOON. Now, I need to replace a headlight bulb, replace front fork seals, clean fork oil off of my front brakes, clean her for the first time since I don't know when, shop for a front tire, test fit my travel gear, figure out why she doesn't like to go from 2nd to 1st, figure out why the Neutral indicator doesn't light, figure out why the rear brake is soft, and get the registration finalized.