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P125X
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P125X
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Glad I stumbled upon this forum as it seems like a very helpful bunch of Vespa enthusiasts. Was forced to sell my silver/maroon '79 P200 about 12 years ago and have waited for the right opportunity to buy another scooter ever since.
So, I just bought my 2nd vespa a week ago -- a shiny red P125X that ran great the first few days, but now seems to get really sluggish, especially uphills after driving around just a few miles. I've adjusted the fuel cock, but that doesn't seem to be doing much. Something scary happened yesterday as I was driving through a tunnel in 3rd gear it just died, locked up and skidded. Started it again, and the same thing happened a minute later. Had to take it home on side streets in 1st and 2nd gear slowly to prevent that from happening again. The strange is it seems to run fine, at least for a few miles, after resting for over night. Any idea what's going on here? I'm pretty confused. Would love any help, if possible, before having to take this back down to the mechanic.
Thanks in advance!
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What I think~
I say this....
Up jet the carb you might just need more fuel.

Dont ride it until you up jet it.
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MV Saint
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MV Saint
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"LOCKED UP AND SKIDDED" Mate, You had a heat seize. Your gonna have some scoring........


Lucky is right here. What main jet are you running? I think theres more here, need more information.

Check to see if your carb is loose. Take the cover off, then check the two 11mm bots that retain the carb to the body. Check the air adjustment.

PM me i will talk you through EVERYTHING to look for

As Lucky said DON"T ride it mate. I'm off to bed, i can talk you throught it tomorrow anytime.

Cheers
OP
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P125X
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thanks so much for the helpful replies. i'll definitely check the carb bolts tomorrow morning, and jim, thanks for your kind offer to help, i'll PM you or reply with my findings here tomorrow. i'm afraid (and a little embarrassed) that i don't know which jet i'm running.

a little more info: this thing has sat for nearly 3 years in a friend's garage. i'm a bit reluctant to take it back to the mechanics who took 10 days to install a new ignition key and pump air in the tires and then told me the thing "was in great shape, and runs perfectly."

thanks again jim and lucky bastard! you guys rock!

j
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GTS300 Super 2023 Beige
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Sounds to me like no oil is getting through the autolube! As you had a P200 before, I am sure you know all about that extra oil tank, and the "glass" below the fuel tap to check it. So the next suspect is definitely the carb and autolube mechanism underneath it.

Mike
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2002 ET4
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I had the exact same issue on my 1980 PX125. It had sat for years and I had the tank re-lined, new spark plug, new fuel and oil lines, etc. It would crank right up, then die about 1 mile away. Wait a while and it would start back up, but I couldn't run it faster than easing along in 2nd gear. The culprit was a partially clogged fuel line- the petcock valve inlet in the tank had some rust flakes in it. So when it sat, the gas would flow through and fill up the bowl. Made you think it was getting gas. But under load, the obstruction in the line starved it out. When I pulled the gas line at the carb, gas was coming through.

One simple test- unscrew the gas cap. Remove the gas line at the carb and see if it's pouring out. Then take the gas line and blow HARD into it. If the flow comes back at much greater volume, you have sediment in the petcock inlet in your tank.
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So mate, I will PM you with my number and i will walk you through it.

It's a Vespa it dosen't get easier mechanically

Cheers
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P125X
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TX_ET4_PX125 wrote:
I had the exact same issue on my 1980 PX125. It had sat for years and I had the tank re-lined, new spark plug, new fuel and oil lines, etc. It would crank right up, then die about 1 mile away. Wait a while and it would start back up, but I couldn't run it faster than easing along in 2nd gear. The culprit was a partially clogged fuel line- the petcock valve inlet in the tank had some rust flakes in it. So when it sat, the gas would flow through and fill up the bowl. Made you think it was getting gas. But under load, the obstruction in the line starved it out. When I pulled the gas line at the carb, gas was coming through.

One simple test- unscrew the gas cap. Remove the gas line at the carb and see if it's pouring out. Then take the gas line and blow HARD into it. If the flow comes back at much greater volume, you have sediment in the petcock inlet in your tank.
yes, this is exactly what happened to me on the same scooter. crazy. ok, i'll try the gas line check you mentioned. thanks for that.

and JimH, thanks a ton for your info, i'll be in touch shortly, buddy.

cheers!
jason
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I totally bypass autolube systems on every 2-stroke I have. I dont trust them. I mix my own and sleep easy.

Good luck
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P125X
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so, thanks to the kind help of the wonderful JimH, i think we've successfully diagnosed the problem. sure enough it was the simplest thing: needing more oil. the shop i had it towed to after buying it put gas in the empty tank but neglected to add 2%. my scooter being a european model it doesn't have the little glass window and it took me some shaking around the open gas tank under a bright light to realise what it so obviously needed.
don't want to bad mouth the shop publically, but really shocked how stupid they were the entire time the had the thing. even JimH (who lived in San Fran for 10 years) said they're a complete joke here in town. unfortunately, the fellow from whom i purchased the scooter said he had a history with them and that they'd been good to him in the past.
whatever, needless to say i'll be going to First Kick and/or any other shops who specialise more in Vespas from now on.
anyway, a HUGE thank you to everyone on here for helping me out with your insightful thoughts and comments, and especially to JimH who took the time to talk to a complete stranger over the phone. i owe him big time. what a wonderful human being.

phew, really feels great to safely take the thing past 2nd gear now.

cheers!

jason
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Thanks mate

I'm glad your happy and safe. This is not the first time that a "Scooter shop" has filled a 2 stroke scooter, minus 2 stroke oil. That's another thread in the making as more people will have to endure these Hamburger Helpers.

Thanks again jason, Ride safe!

Cheers
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2020 Honda NC750DCT
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Veni, Vidi, Posti
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Special MV award for Jim! Clap emoticon Clap emoticon Clap emoticon

That kind of help makes this community rock!

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