Sorting out my "Pexmor" 49 cc motor...

Glad its running good. Once you get a tank or two through it should have better torque.

Tape some rags or paper towel to the bottom bracket after spraying rust remover on it. Got a coaster brake shell that looked like it was made of clay looking brand new that way.
 
cloakedvillain said:
Glad its running good. Once you get a tank or two through it should have better torque.

Tape some rags or paper towel to the bottom bracket after spraying rust remover on it. Got a coaster brake shell that looked like it was made of clay looking brand new that way.
Click to expand...
About to take it out for an actual longer ride, see how it does. IDK why it's so weak until it warms up, but this time I plan to run it till it's fully warm and see what it has. Also I wanna see if the plug color gets better. It can't be set any richer without a larger jet, and it's now running a carb jetted for a 66cc.

Is there a difference in the jets used on a 49cc vs a 66cc? It's now got a carb set up for a 66cc set at it's richest setting, so if there is a difference, IDK why it needs so much fuel?
 
Well I rode it around, and again for a full minute or two it was a DOG, and it doesn't like starting unless you get decent speed pedaling first. Once it warms up though it is now what I would call "viable transportation". I don't know if it will climb hills as handily as the CMB motor, but it would be close. It does have the 44 tooth sprocket on it opposed to the 41 tooth on the PK80. I'm scared to take it down the big hill, but it went up a moderate hill very well with a head start, it struggled on another with no head start, but the pedal assist wasn't strenuous. As a backup this thing is great now, I really appreciate it!

I will try it up the big hill soon, but on a cooler day, just in case I kill it and have to walk...

I doubt I will though, I think it will tackle the big hill nearly as well as the PK80. You can get a decent head start most of the time, and if it needs a little pedaling, it shouldn't be bad, not enough to wind me. We will see soon I spose...
 
markjs said:
Is there a difference in the jets used on a 49cc vs a 66cc? It's now got a carb set up for a 66cc set at it's richest setting, so if there is a difference, IDK why it needs so much fuel?
Click to expand...
motoredbikes.com

I've asked this in multiple threads but..?

So I have a 49cc engine I did not buy, and a PK80 Wildcat from CMB, and an install kit for a PK80 also from CMB. I ditched the Pexmor's carb because it has a float problem and overflows. I'm using the new carb from the PK80 kit... So the question is, are the carbs jetted different on 49cc kits...
motoredbikes.com motoredbikes.com
 
This still looks too lean to me?

IMG_20240508_215239.jpg


Am I gonna have to buy jets for my NT? That's after a good fully warmed up ride (shorth though). Seems like if it's still to lean that I could get even MORE power from it? If so it's one mighty little 49cc motor!
 
markjs said:
This still looks too lean to me?

View attachment 213007

Am I gonna have to buy jets for my NT? That's after a good fully warmed up ride (shorth though). Seems like if it's still to lean that I could get even MORE power from it? If so it's one mighty little 49cc motor!
Click to expand...
Where's the clip at on the needle? Did you just pull that after a ride?
 
markjs said:
Richest setting, and yes, after it cooled down.
Click to expand...
So, all the way to the bottom? To do a proper plug reading you have to ride the bike under load for at least 5 minutes after it is warmed up. Then kill the engine, don't let it idle down, coast to the side and pull your plug. Bring some gloves, it'll be hot.
 

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