Alpha Sports LG90 Mini 4 Wheeler

Well, I've been debating making a thread on this, but I guess I will. Anyway, I got this little four wheeler from the gentleman I sold the Craftsman to. I don't think it has spark... And I do think it has a CDI, and I have no clue how that contraption works. Everything is kinda tight, so it definitely wants some WD40. I think the tires are good. Anyway, school restarts on the 11th er somethin like that, so that's why I've been tryin to get a lot of projects rapped up lately. But this is gonna be one of the over-the-school-year projects. So I'm gonna go 'head and stick er down in the portico er somethin and forget about it for a little while. Just thought I'd post up the new contraption. I have no clue what I'm gonna do with it right now, but hey, we'll do somethin with 'er!




Compared to the Avanti, it doesn't seem so small...



And for anyone wondering, I was told that it was a 125cc.

CDI = Capacitor Discharge Ignition?
A lot of outboard motors had that when I was a teen.
I think it needs a good battery and a good Igniter (electronic gadget between battery and coil). Timing is from a pickup near the flywheel.

Yeah it's something like that. A battery is gonna be my next try. Maybe I'll clean up the connections and see what I get. Gotta do some research on the whole CDI world first though.

Welp, decided to screw around with it a little. Pulled the body panels off to get to everything, then my brother pressure washed it, then we got the front brakes freed up, and now we're trying to actually get it running.




For some reason it's getting negative and positive power from the alternator (more neg the pos), it makes it to the CDI and all those weird contraptions, makes it back out of the CDI still strong, but when it gets to the coil, the -/+ power is super weak.

We also put a lawn mower battery on it for the time being. When we first put it on, the wire that goes to the starter was already broken off, and always had power until I touched it up against the starter post... Then it just went black until I let off. And it doesn't matter what you do, it constantly had power, so I think the starter might be blown.

I also touched what appears to be the fuse connections together, and when I did that, the low oil sensor (at least that's what it appears to be) started smoking. So I'm confused. The main switches aren't doing anything at all. But for now I just want spark. I don't know, I guess I better start questioning the resistor.... (whatever the heck that does).

Oh, I also found out that this is actually a 90cc 2 stroke with a real torque converter.

Okay, so I don't know what all happened, but I do know my brother pulled the whole wiring harness and went through the whole thing. It had spark after that. He also rebuilt the starter and carburetor. Then we took it for a rip and tuned it a little. After that we put it all back together minus the air box. Still could use a new carb. It also needs a relay and stuff like that. But the kick start does fine for now.





It's running alright now. Still needs a carb or something. The brakes seem a little worn, but it'll be fine. Hopefully I don't get hurt on this thing. Eventually I'll sell it, but I haven't abused it anywhere near the amount I hope to, so.

Sounds like there may be a loose ground in there somewhere.

I don't know. It's all too confusing for me. I still don't know what was causing the spark issue. My brother got it working pretty good so I'm gonna get a battery for it and try the relay first. I think that'll take care of it. Who knows. At least I know the starter is good. Once I put the relay in it and a battery I think all the electrical gremlins will be eliminated......... But don't quote me on that.

Well, I haven't done anything but put a new carb on it so far. Still very very picky about air/fuel mix. I'll eventually get it. Don't have the time to work on it right now. Anyway, I'll try to make a full video of the abuse it goes through when I get some footage. Here's some pics I took right before a storm. I didn't know this was a storm and ended up getting slammed by it while riding the 4 wheeler.





4 Wheeler Update 8/29/20

Okay, so as you can see, I had this thing running pretty good. I send it off jumps and drift it and 2 wheel it on a weekly basis. I was abusing for maybe a month since that's about how long it lasted before it started running like crap again. Now I can barely get it going when it's cold. But I'll get to that at the end. We'll start by saying that I finally got that battery and relay. I had to hook up the starter wire because I forgot it was disconnected. Once I did that the starter worked. I think there's an electric choke on the carb that doesn't work, but that's because it's disconnected. Oh, and a resistor is burned out, but I think it'll be fine. I put new front brakes on it and new headlights. The front brakes were never adjusted right when I put them on, and after it did some harsh rolling and front flips during a wreck, the handlebars got crushed and that finished off the front brakes. The new headlights are starting to fail already too. I don't know why yet. The taillight only works as a brake light now too. The body is absolutely decimated. The rear brakes are going out too now. The front end is starting to have some camber and toe out. The starter is going out. It leaks oil. This is one sick puppy.



So, as you can tell, it's running anything but good. I don't know if it's piston rings, or an electrical issue, or gaskets or what, but I don't think it's gonna be worth my time. I'm gonna take it to a shop this week and see what he thinks, but if it's anything major, I'll probably sell it if I can get a couple hundred for it. If not, I'll consider parting it out if I like the suspension components. But as of now I don't think the suspension components are worth it. So I'm most likely gonna sell it this winter unless I can get some more abuse time out of it. We'll see. Tell me what you think it could be.

Welp, I almost sold it. Had a guy come look at it but it was running just bad enough that he didn't want it. That's fine with me. I managed to get it to run better so I thrashed it for like an hour and a half. Anyway, yeah it has to be rebuilt. I don't know if I'm gonna rebuild it or not yet. As for the moment, we're just gonna send it. And when I say send it, I mean I'm gonna be an IDIOT.





Yup, we did the ol' nitrous can modificontraption... Gave the ol' girl at least 2.833 hrsprs. Just give 'er a little shot, and she starts roarin' back to life.

We'll see how long she lasts I guess.

Welp, I put it to bed about a month ago. Tried to get it going for Rockcrusher but that was a fail. Dumped a bunch of ATF in the fuel but it wasn't enough to handle anything more than an idle. So I put it out behind a garage and covered the clutch area cause it fills with water and doesn't move. So it's gonna sit there until I figure out what I wanna do with it.

Thinking about rebuilding it, but I really don't know. Everything on it is beat to heck so I'm not sure yet. All I know for sure right now is that it's just gonna sit behind the barn until I figure out something to do with it unless someone sees it and makes a good offer on it.

Just discovered the thread. Cool rig! It looks kinda small to me but that’s cause I’m used to running the grandparents’s Yamaha Beartracker 250. The insane part of me says do another build and call it the Alpha Murray...but my advice has a tendency to backfire so maybe take it with a grain of salt I guess. Hope it all works well for ya!

Edit: just realized it is a mini four wheeler, now feeling kinda stupid lol

I don't why but my brother got another 4 wheeler. For some reason now I want to get mine going. So I pulled it up to the shop today and dropped the motor and pulled the top end apart. It looked way better than I thought it would. Now I have to assume it's gasket related. I will get some more photos of everything later. I need someone who knows more than me about 2 strokes to chime in here. Y'all know what's been going on with it. I've shared the problem over and over through this thread. I should've sold it and bought another but whatever. I guess I'm gonna try to get this thing going strong again.









Please read through the issue that I've been having and post anything that could be linked to this problem. I really don't wanna put this thing back in just to have the same issues.

I made a major mistake trying to bring this back. I am currently in the hole $325+ on this thing not including the previous $125 I dropped on it last year. I have boxes and boxes of motor related parts for this thing. Just like always, I did it again. I took it too far.




New crankshaft, con rod, jug, ALL gaskets, air box, head, piston and rings, reed valve, intake, plug, rod and crank bearings, belt, oil pump, and the list goes on. So basically, I bought a brand new engine for this thing, I just have to put it together. It better outperform everything in it's sight when I'm done with it or out the door it goes.

The engine block is pretty much 90% stripped. Once I get the block all cleaned out, the reassembly finally starts.

One thing is for sure though, THERE WILL BE NO STALLING HERE ANYMORE.

Remember...if it still stalls, you can always put in a big Honda clone and build a crotch rocket.



Hope the rebuild goes well for ya...that is quite the expensive kit there.

And it only gets worse, lol. Now I bought a new starter and air box. Anyway, the rebuild is 99% done. Just a few small odds and ends to tie up on the motor.





But now I'm wanting the 4 wheeler itself up to par with the engine. Great. More money. Anyway, I'm going to rip the wiring out and try to find an aftermarket one that will run everything smoothly and pretty much be a direct hookup. I also still need all the fuel lines and bushings for the front end and fix the brakes.

Welp, I tore this thing completely apart but I don't have pics. So here's before and after:





So... A LOT has happened to this boi.

It has been repainted, new rear shock, new chain, new engine sprocket, new fuel and oil lines, new fuel filters, new duct work, all new vent plumbing, new control switch, new LED taillight, plus the entire engine that is basically brand new. The internals haven't even been exposed to gasoline yet.






Yes I painted the muffler gold lol. I like how it looks. It'll really go good with the blue. I have determined at this particular point, I have more money in this than I do in the Mountain Murray. That's just sad lol.

There is a lawn tractor somewhere that would be proud to wear a bunch of parts off that rig.

Nevadablue wrote:

There is a lawn tractor somewhere that would be proud to wear a bunch of parts off that rig.

I sure wish that's what happened. I am never going to financially recover from this...

Unfortunate news for this one. This thing is goin' away. I have wayyyyyyyyyyyyyyyy to much money in this thing now to not sell it. I have no choice if I want to make any money next year. Gotta have some cash to go grab some tractors and flip 'em over the winter to be ready for the mowing season. Also got the F-250 now which is wayyy more important to put money into than any old 90cc quad. If I can get my money back out of this or at least most of it, I'll be more than happy.




So recently, I was finally able to find used wiring from a 90cc Polaris Scrambler that fit this perfectly! So I put that on, made the last order of oddball parts, put those on, and then cycled the motor since it had never been ran before. This is where the story goes bad... Towards the end of the second cycle, while I was just sitting there playing with the throttle, I gave it some throttle and once the RPMs got up, it just went, *clank clanK claNK clANK cLANK CLANK CLUNK,* and locked up. At that point I shouted in agony and quite literally beat my head against the door. Somehow, it didn't blow up. At the time of this post, it has done it to me about 7 times now. Here's a video of what it's doing. I haven't even started it since this video.






Anyway, still debating on whether or not it's worth putting my time into it. If it's simple, then I'll take care of it, but if not, I am selling it as is and that will be the end of this thread. I can't wait for that. This is simply the biggest financial mistake I have ever made... and I ain't kiddin' ya.

I think it is overheating and locking up maybe. Have you looked at the plug? Running WAY lean? Been a long time since I have worked on 2 stroke engines like that but...

It just sounds like it quit to me, does the motor actually lock and you have to break it free? What kind of oil are you running and at what ratio?

Also I noticed you mentioned an auto choke, when they get sticky they're problematic, the electric solenoid isn't very strong so it can't overcome much... it seemed to die right as it was warming up that's why I've mentioned it.

I do know quite alot about 2 strokes big and small, I have a Suzuki LT250R and do all my own work and maintenance on it so if you want to chat and get into details let me know.

Nevadablue wrote:

I think it is overheating and locking up maybe. Have you looked at the plug? Running WAY lean? Been a long time since I have worked on 2 stroke engines like that but...

I have looked at it. It still looks brand new. Even with 4 years of experience in mechanics, I'm still learning how to read plugs lol. Might be running lean. I'm considering another new carb for like 20 bucks since that's the last thing left from before the rebuild. I tuned the living crap out of it in all sorts of ways trying to get it to run good and never succeeded so it's probably screwed up.

Brianator wrote:

It just sounds like it quit to me, does the motor actually lock and you have to break it free? What kind of oil are you running and at what ratio?

It doesn't actually lock, but it sounds like it is. I guess I should've clarified that. I'm running the cheap Walmart conventional 2 stroke oil. I have no idea what the mix I'm running is but shouldn't matter cause this atv has a self-mixing system. I still mixed the fuel with some oil tho because it had never been ran.

Brianator wrote:

Also I noticed you mentioned an auto choke, when they get sticky they're problematic, the electric solenoid isn't very strong so it can't overcome much... it seemed to die right as it was warming up that's why I've mentioned it.

I do know quite alot about 2 strokes big and small, I have a Suzuki LT250R and do all my own work and maintenance on it so if you want to chat and get into details let me know.

I actually swapped the electric choke to one that had been modified so it doesn't move and just stays open to see if it helped and it didn't.

Yes actually that might be a good idea. When I get some time I'll tag you in the chatbox when I see you online if ya want. Thanks!

Sounds good man, I'm usually around in the evenings!

I personally prefer to mix my own fuel so I KNOW it's good go, the oil injectors seem fairly reliable from what I've heard but it's just another possible thing to go wrong in my eyes and there's too many variables.

I won't get into to many details here it will be easier to talk in the chatbox but yes tuning 2 stroke carbs can be quite tricky and is essentially done the opposite of what most people think, you may already know that though.

Okay so this was my final attempt at fixing this thing. I put a brand spanking new carb on it and here’s what it does. (Apologies for my frustration in the clip lol)



What do y’all think it could be? I’ll try whatever y’all say cause I’m done fighting with this hunk of scrap.