markjs
Well-Known Member
That does look like a sweet little machine. I wonder if the smaller wheels had anything to do with it running so well?
Sorting out my "Pexmor" 49 cc motor...
- Thread starter markjs
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Chainlube
Well-Known Member
It wasn't real fast, maybe 25. It did pull up a hill good though maybe 15-20, never had to pedal it up a hill. I sold it to a guy that needed it to go to work on. After a year he sold it to another guy that needed it to go to work on but had a longer commute.
markjs
Well-Known Member
Man I'm bummed out; the parts came and were delivered and I can work inside, but it's raining and nasty out, and I mean hard enough I don't wanna test ride anything today. I still may do some of the work, but not being able to go try it out and enjoy my labor takes a lot of the motivation away.
D
Deleted member 33057
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You didn’t say how steep of an incline the hills are you’re having trouble getting up..
I know this.. a 49cc stock tuned right is a decent engine. I helped someone with one. It had a 36T and ran well. It did need a little pedal assist but after rolling it pulled.
We didn’t know it was a 49cc until we took it apart after a couple years of running. The guy bought it under the assumption it was a 66/80cc.
This was used all on flat ground…no hills but at its best he’d run 30mph or so.
I know this.. a 49cc stock tuned right is a decent engine. I helped someone with one. It had a 36T and ran well. It did need a little pedal assist but after rolling it pulled.
We didn’t know it was a 49cc until we took it apart after a couple years of running. The guy bought it under the assumption it was a 66/80cc.
This was used all on flat ground…no hills but at its best he’d run 30mph or so.
A well tuned 49cc with a few "builders tweaks" can keep up with most 66cc motors in most scenarios. I put one together for a friend and simply set a tight squish gap and cleaned up the ports a bit with a little port matching. Left the intake rough from a double cut burrs and lightly polished up the exhaust with fine scotchbrite bits on my rotary tool. He tops out at about 28-29mph on a 44 tooth sprocket on a 26 inch wheel.
He uses it to get to work and run small errands in his little town. It's not much for torque, but it can manage average hills with a little slowing down and some peddle assist.
He uses it to get to work and run small errands in his little town. It's not much for torque, but it can manage average hills with a little slowing down and some peddle assist.
markjs
Well-Known Member
Well then this thing is not running like it should. If I assume my 66cc is about 2.5 HP, then this thing is putting out like less than one now. Anyway I got my other bikes bars done, so now I can focus on getting this thing running. I know the carb leaks because the float needle isn't closing for some reason, yet it is still running lean? That seems very odd to me, but I will clean that carb later, as I have a brand new unused carb that came with my kit, so I plan to just slap it on the engine and tune that, hopefully it won't leak or have any problems. It does have one of those red "scoop" type air cleaner, where this had the black thing (now on my 66cc cuz the red won't fit), so I assume it was an older carb
In any case I have a brand new one, so all I need is an O-ring for it, and two bolts for the clutch cover (the engine came with a partial spring type chain tensioner), and it wouldn't fit between the extremely narrow cranks, so the bolts were too long after removing the plate.
I expect to get it running good, then it will probably sit a lot. That bike just isn't NEAR as comfortable to ride as my new one, especially since I got the bars on it! I ordered this GREAT cable set from Amazon. It came with cable cutters that work very well, extra cables, ends and anti fray ends too.
But it will probably get to go on occasional quick trips to the store. Plus if for any reason anyone ever wants to try out a motorized bike and ride with me, there then exists that possibility too. Mostly I just enjoy the satisfying feeling of having made things work at their optimal level.
markjs
Well-Known Member
Here's the end result of the other bike, the "daily driver"...
markjs
Well-Known Member
Well just like last time I wasn't motivated to do anything till late in the day, but I got the new carby on, fixed the tank and petcock issues, moved the needle to it's richest...
Now IDK if a PK80 carb has the same jet as a 49cc? If so it's set to one richer than it was before. It ran really doggy at first, but after it warmed up it was WORLDS better. IDK that it's "dialed in" now, but it motivates me and my fat ass!
I judged my Peugeot a bit too harshly. It does let you feel the bumps, being fully rigid, but it rides better and is way more comfortable than the Roadmaster as it comes off the Walmart showroom. It's a good bike for a rigid frame, and from what I could tell once that little Pexmor was warm, it will be a worthy backup bike!
The chain is too tight though, it makes "stress sounds" so I will have to attend that, add a link, and thus probably a chain tensioner. I thought it was just right, but it's too tight, that will wear s**t out if I ride it like that much. I'm not looking forward to the job though. I have a decently working chain breaker big enough for this chain they use, but it is NOT easy to crank that thing! It's just kinda barely within my hand strength to break them initially, and it means re-centering it on the pin a bunch until you sink the pressure pin into the chain a little.
I may do it tonight, I am in kinda a "get it done mood" but then IDK, I hate busting chains.
Anyway I'm impressed by that little motor. I'm guessing it's hitting near 2 horsepower now....
She's ugly but she works again!
The rusty muffler looks terrible I know, but it's the only one that can be made to fit without the cranks smacking it. The Peugeot has an extra narrow crankset, even the added thickness of the plate of a spring chain tensioner over the clutch cover would require wide cranks. The bottom bracket of that Peugeot is so old and crusty, I don't think it would come apart. I know the seat tube is permanently fused to the frame. The Roadmaster has it all over the Peugeot as far as long term viability, once the Peugeot's bearings and stuff are shot, will be time to replace it, but she's running fine for now....
Now IDK if a PK80 carb has the same jet as a 49cc? If so it's set to one richer than it was before. It ran really doggy at first, but after it warmed up it was WORLDS better. IDK that it's "dialed in" now, but it motivates me and my fat ass!
I judged my Peugeot a bit too harshly. It does let you feel the bumps, being fully rigid, but it rides better and is way more comfortable than the Roadmaster as it comes off the Walmart showroom. It's a good bike for a rigid frame, and from what I could tell once that little Pexmor was warm, it will be a worthy backup bike!
The chain is too tight though, it makes "stress sounds" so I will have to attend that, add a link, and thus probably a chain tensioner. I thought it was just right, but it's too tight, that will wear s**t out if I ride it like that much. I'm not looking forward to the job though. I have a decently working chain breaker big enough for this chain they use, but it is NOT easy to crank that thing! It's just kinda barely within my hand strength to break them initially, and it means re-centering it on the pin a bunch until you sink the pressure pin into the chain a little.
I may do it tonight, I am in kinda a "get it done mood" but then IDK, I hate busting chains.
Anyway I'm impressed by that little motor. I'm guessing it's hitting near 2 horsepower now....
She's ugly but she works again!
The rusty muffler looks terrible I know, but it's the only one that can be made to fit without the cranks smacking it. The Peugeot has an extra narrow crankset, even the added thickness of the plate of a spring chain tensioner over the clutch cover would require wide cranks. The bottom bracket of that Peugeot is so old and crusty, I don't think it would come apart. I know the seat tube is permanently fused to the frame. The Roadmaster has it all over the Peugeot as far as long term viability, once the Peugeot's bearings and stuff are shot, will be time to replace it, but she's running fine for now....
markjs
Well-Known Member
IDK if this is because I haven't run it enough with the new carb and needle setting, but it still looks very lean to me!
Maybe it just needs more run time? it may be a little better than before, I mean it certainly ran better.../
Maybe it just needs more run time? it may be a little better than before, I mean it certainly ran better.../
markjs
Well-Known Member
I couldn't just let it sit, so close to "done"; so I added a link and a half to the chain, threw on a tensioner, and she's ready to ride and tune to tip top shape tomorrow. I wanna ride it "as is" a bit more and see if the plug color comes in more "right".
I made my mix 25:1 since he said this engine is still not fully broken in. I figure my PK80 can handle the extra oil while this breaks in some more, since it normally runs 32:1, 25:1 shouldn't hurt it too badly...
Seems odd to me that the 66cc PK80 Wildcat seems to run best at the leanest needle setting where the 49cc is running best at the richest? Oh well, whatever makes it run best right?
They say you can't tell the difference between the two sizes, but if you get down and look at the jugs straight on, you absolutely can tell one is a 49cc and the other a 66cc. At least between the PK80 and the Pexmor 49cc. The jug is really small!
I'm also not sure if I recall the PK80 being this way, but the difference between cold and warmed up in the Pexmore 49cc is night and day! It's so much stronger after it runs a few minutes, I mean it barely pulls at all until it has ran a bit. If there was a difference with the PK80 it was for a much shorter time and not as dramatic.
No lights or I'd go ride it around now. I can see fine, I just can't be "seen" so easily, so that can wait till tomorrow. It's kinda exciting to have two functional bikes "in the stable" too bad parts had to be robbed from my only functional pedal bike to make it happen (tube and the bars). I don't wanna put flat bars on the pedal bike though, so more "ape hangers" will need to be found...
Tomorrow, more fun, and hopefully at the end, two tuned machines!
I made my mix 25:1 since he said this engine is still not fully broken in. I figure my PK80 can handle the extra oil while this breaks in some more, since it normally runs 32:1, 25:1 shouldn't hurt it too badly...
Seems odd to me that the 66cc PK80 Wildcat seems to run best at the leanest needle setting where the 49cc is running best at the richest? Oh well, whatever makes it run best right?
They say you can't tell the difference between the two sizes, but if you get down and look at the jugs straight on, you absolutely can tell one is a 49cc and the other a 66cc. At least between the PK80 and the Pexmor 49cc. The jug is really small!
I'm also not sure if I recall the PK80 being this way, but the difference between cold and warmed up in the Pexmore 49cc is night and day! It's so much stronger after it runs a few minutes, I mean it barely pulls at all until it has ran a bit. If there was a difference with the PK80 it was for a much shorter time and not as dramatic.
No lights or I'd go ride it around now. I can see fine, I just can't be "seen" so easily, so that can wait till tomorrow. It's kinda exciting to have two functional bikes "in the stable" too bad parts had to be robbed from my only functional pedal bike to make it happen (tube and the bars). I don't wanna put flat bars on the pedal bike though, so more "ape hangers" will need to be found...
Tomorrow, more fun, and hopefully at the end, two tuned machines!
