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Purchasing used buddy 50 that smokes up badly. Run away?

 
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venmike
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Location: houston
buddy 50

PostPosted: Tue Apr 02, 2019 6:45 pm    Post subject: Purchasing used buddy 50 that smokes up badly. Run away? Reply with quote

Hi all,
I found a killer deal on a used 2008 buddy 50 with 3k Miles for $350
It’s in decent shape and runs. Howver, the motor smokes up pretty badly.
The owner says she let it sit for a good while without starting it. She says it has old gas, and carbs probably need to be cleaned. How reliable are these motors? Does her story add up? Is it fairly easy to clean the carbs ?

I also notice that the hose that connects to the fuel filter is broken, and there’s a gaping hole in the filter. I’m not sure if these are the correct terms, as I’m not technically savvy.

Should I pick this thing up?
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cummingsjc
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Genuine Buddy 50cc, Genuine Mean Cat, Piaggio MP3-500 (Desert Camo), MP3-400 (Pinky)

PostPosted: Tue Apr 02, 2019 8:14 pm    Post subject: Reply with quote

Personally, I would buy it in a heartbeat for that price with the discrepancies that you mention. The smoke will normally go away after you burn out the gunk in the engine with a longish ride. Everything else should be easily repairable. Ensure that the bike's frame seems straight and everything tracks true if you give it a ride.

Buddy's are very easy bikes to resurrect after they have sat for a few years. And, Buddy 50's are some of the best 2-stroke 50's that you can buy.
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venmike
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buddy 50

PostPosted: Wed Apr 03, 2019 12:38 pm    Post subject: Reply with quote

Guys I need help!
I purchased it, but it’s smoking up so badly when I ride!!!! Massive smoke, and smells like something is burning. It runs fine, idles fine.
But the smoke is ridiculous, and making me sick when I ride it.
What could possibly be causing this much smoke from the tail pipe? Could the motor be shot??
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skully93
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currently 09 Buddy Italia, Honda CTX700DCT

PostPosted: Wed Apr 03, 2019 2:29 pm    Post subject: Reply with quote

venmike wrote:
Guys I need help!
I purchased it, but it’s smoking up so badly when I ride!!!! Massive smoke, and smells like something is burning. It runs fine, idles fine.
But the smoke is ridiculous, and making me sick when I ride it.
What could possibly be causing this much smoke from the tail pipe? Could the motor be shot??


I doubt it. probably it's just been sitting for a long time.

It is a 2-stroke, so it will smoke a lot.

Probably a good idea to put a bit of seafoam in the gas, and give it a good ride.

If it idles and runs as normal, it's just old oil.

it's also remotely possible they put the wrong oil in it? Maybe drain it and refill?

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skipper20
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170i

PostPosted: Wed Apr 03, 2019 3:10 pm    Post subject: Reply with quote

cummingsjc wrote:
Personally, I would buy it in a heartbeat for that price with the discrepancies that you mention. The smoke will normally go away after you burn out the gunk in the engine with a longish ride. Everything else should be easily repairable. Ensure that the bike's frame seems straight and everything tracks true if you give it a ride.

Buddy's are very easy bikes to resurrect after they have sat for a few years. And, Buddy 50's are some of the best 2-stroke 50's that you can buy.


Try draining or pumping out the old 2T oil from the oil reservoir and refill with new 2T oil (the owners manual will give you the right type) and run it for awhile. You should also drain the old gas if you haven't already done so. If it still smokes, and since you're not technically savvy, take it to a scooter/MC repair shop. Or a Genuine dealer if you have one nearby. Use the money that you saved on this killer deal and get it fixed properly including the fuel filter issues. Good luck and welcome to the forum.

Bill in Seattle
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venmike
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buddy 50

PostPosted: Wed Apr 03, 2019 3:38 pm    Post subject: Reply with quote

How do you drain the oil and gas? Is there a drain bolt somewhere? Thanks
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tenders
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Buddy International 50 Italia

PostPosted: Wed Apr 03, 2019 7:00 pm    Post subject: Reply with quote

You can drain it from the tank by siphoning it out of the fuel fill, or by removing the vacuum-activated petcock at the bottom of the tank (look up at it from the back of the scooter, it’s easy to see/access) and catching it in a container.

You can drain it from the carb by removing the two horizontal bolts that connect the carb to the manifold, and disconnecting the carb from the air filter on the other side by loosening the clamp (a lot). When you take the carb out, it will still be connected to the fuel and vacuum lines from the petcock, the throttle cable, and the electrical wires to the choke, but you can still lift the carb and loosen the drain screw that is the lowest screw on the carb bowl. Once you do that, lowering the carb below the level of the tank (near where it was originally mounted) will make everything drain out the drain tube, where it can be caught in the container. Then reconnect the carb and make sure the connection to the air filter is airtight. This can be a little tricky.

This shouldn’t take even an hour to do. If you have to do it again it shouldn’t take more than ten minutes.

I would say it is great news if the scooter is running on the old gas, even if it isn’t running well. Before you siphon out the 2T oil, try putting a quart of nice fresh gas into the emptied fuel tank with a healthy dose of SeaFoam, and see if the smoking goes away. The oil may be perfectly fine.


Last edited by tenders on Wed Apr 03, 2019 10:53 pm; edited 1 time in total
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venmike
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PostPosted: Wed Apr 03, 2019 7:49 pm    Post subject: Reply with quote

Thanks.
Do you add seafoam to gas tank or do you add it to the 2T oil reservoir?
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tenders
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Buddy International 50 Italia

PostPosted: Wed Apr 03, 2019 8:53 pm    Post subject: Reply with quote

Just to the gas. It supposedly has a solvent effect on lingering crud in the carb, and preserves fuel (but does not magically restore old fuel to good condition).

I frankly have my doubts as to its efficacy, because fresh gas is already a pretty good solvent, but it does no harm unless you use too much. A lot of people swear by it.

EDIT: I see I was imprecise about that...put the fresh gas and the Seafoam into the fuel tank. Don’t put anything into the 2T oil tank except 2T oil intended for injection (not “premix” oil).
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venmike
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PostPosted: Thu Apr 04, 2019 3:24 am    Post subject: Reply with quote

Update: I found a way to drain the oil. I put fresh 2T oil. I put fresh gas and some carb cleaning additive. I rode it hard for miles, and it’s still smoking the same way it did previously. Has not improved at all. I thought that it may just be burning off the fuel additive, but it still continues to smoke despite riding it hard for miles and miles.

I’m so confused by this.
This is NOT a normal amount of smoke. I’ve owner 50cc scooters in the past and they have neve Smokes this badly. It’s so bad that I cannot even ride the scooter. The smell is making me physically sick. It’s a nasty burning smell that is killing my lungs.

I may have to let this on go.

Does anyone have any other ideas of what it could be? It runs great. Has great power, idles great, no issues and all. No hesitation. It starts right up on the first push/crank. It just smokes like crazy! It smokes even more when. It’s fully warmed up!

So frustrated.
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tenders
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Buddy International 50 Italia

PostPosted: Thu Apr 04, 2019 9:57 am    Post subject: Reply with quote

Don’t give up yet. If she’s running this well and smoke is the only issue, there is almost certainly some minor thing causing a big fat rich mixture that will be obvious...once you find it.

Is this the air filter clean? Easy fix, take out four Phillips screws and remove the black plastic cover on the left side of the engine above the kickstarter.

Have you adjusted the air/fuel mixture screw? Not the plastic idle speed thumbscrew, the screw next to it. Easy fix but you might need to track down a special D-shaped screwdriver. I believe tightening it makes it leaner.

With it starting and running this well I’m not inclined to suspect anything is wrong inside the carb, what do other people think? Does the oil injection process ever need calibration? Doesn’t seem to have been discussed here much but could account for a lot of smoke.
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Stanza
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PostPosted: Thu Apr 04, 2019 1:51 pm    Post subject: Reply with quote

venmike wrote:
Update: I found a way to drain the oil. I put fresh 2T oil. I put fresh gas and some carb cleaning additive. I rode it hard for miles, and it’s still smoking the same way it did previously. Has not improved at all. I thought that it may just be burning off the fuel additive, but it still continues to smoke despite riding it hard for miles and miles.

I’m so confused by this.
This is NOT a normal amount of smoke. I’ve owner 50cc scooters in the past and they have neve Smokes this badly. It’s so bad that I cannot even ride the scooter. The smell is making me physically sick. It’s a nasty burning smell that is killing my lungs.

I may have to let this on go.

Does anyone have any other ideas of what it could be? It runs great. Has great power, idles great, no issues and all. No hesitation. It starts right up on the first push/crank. It just smokes like crazy! It smokes even more when. It’s fully warmed up!

So frustrated.




Don't lose hope just yet. The oil pump is not adjustable, it either works or it doesn't. Fortunately, there are two possible explanations for heavy smoke (like a spy movie smokescreen) from the tailpipe, and both are easy to diagnose. This is a long one, hope you don't mind reading.

Scenario one: The previous owner consistently used low grade two cycle oil, and the muffler/catalytic converter is seriously gunked up, and is trying to burn off the buildup, which would produce heavy smoke. If this is the case, simply running high grade oil (JASO-FD is the required oil for these bikes btw) will eventually see that buildup burn off, and a much cleaner running bike.

Scenario one and a half: You just drained out the old oil, but there may be remnants of the old stuff in the lines. If there is, and if it was crappy oil, you may still be burning off the bad stuff.

Scenario Two: The oil pump has failed in such a way that it is delivering way too much oil into the engine. The pump has a valve inside it that keeps the oil from tricking down into the cylinder while the bike is off. If this valve fails, you basically end up having to burn off extra oil compared to normal. If this is the case, you may need to replace the oil pump.

Now for the important part, how to tell which scenario applies to your bike!
On the exhaust pipe, right on the pipe itself, you will see a bolt. I've included a picture for reference. Remove this bolt, and start up the bike. Wear earplugs, it's going to be loud.

What you're doing here is letting the exhaust out of the pipe, before it gets to the catalytic converter. Let the bike warm up, and observe the amount of smoke coming out this hole (bypass port), vs what you usually see coming out the tailpipe. If it's less, then your catalytic converter/muffler is just gunked up, and you need to either run the bike with the right oil until it has a chance to burn all the old stuff out, or consider starting fresh with a new muffler.

If the amount of smoke you see coming out this hole (bypass port) is just as much as usual, and it's still choking you out and making birds fall from their perches, then you likely have an oil pump problem. If that's the case, you may want to swing by your nearest Genuine dealership to see if they can swap it out.

TLDR: Probably oil related, need to diagnose.
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venmike
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PostPosted: Thu Apr 04, 2019 2:19 pm    Post subject: Reply with quote

Actually,
I notice that the hose that connected to the small canister above the exhaust is broken, and there’s actually a large hole in that cannister. However, there’s no smoke coming from that hole. Should there be?

I pointed this out to local buddy mechanic, and he said it would not cause it to smoke up.

The mechanic actually told me it’s normal for it to smoke up like this. He’s crazy...definitely not normal. I think he just didn’t want to do the work for me.


Last edited by venmike on Thu Apr 04, 2019 2:59 pm; edited 1 time in total
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venmike
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buddy 50

PostPosted: Thu Apr 04, 2019 2:21 pm    Post subject: Reply with quote

Edit: it’s that little black canister right above the tail pipe.
There’s a hose connected to it. I can see it in the photo you posted.
What is that thing?
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Stanza
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PostPosted: Thu Apr 04, 2019 3:09 pm    Post subject: Reply with quote

That canister is there to help reduce smoke, yes. See this post for more info on the subject:


http://www.modernbuddy.com/forum/topic31705.html


Basically that canister is part of the system that introduced oxygen into the catalytic converter to help heat it up. The hotter it gets, the better it can burn off the oil residue and gunk that's coming out of the engine. With that canister broken, you may have a cat that's been gradually been getting more and more gunk buildup because it just isn't getting hot enough.

As for the local mechanic who sounds like they just don't want to work on your bike....eh, maybe try someone else. Here's a link to the Genuine Dealership locator, maybe one of those is close enough to help?

http://www.genuinescooters.com/dealers.html

The bike should smoke a little, but it shouldn't be excessive, and certainly not enough to leave a huge cloud behind you.
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venmike
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buddy 50

PostPosted: Thu Apr 04, 2019 3:49 pm    Post subject: Reply with quote

This is interesting.
I’m going to disconnect the exhaust and see if the smoke goes away.
You may have just solved this issue. I’ll report back!
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venmike
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buddy 50

PostPosted: Thu Apr 04, 2019 10:34 pm    Post subject: Reply with quote

Hi stanza
I unscrewed that screw you mentioned above that connects the exhaust.
Are the fumes supposed to be coming from that screw hole? Or did you mean to dismantle the entire exhaust??

There was smoke coming from the screw hole, and it did not change.

So I guess this means I have a bad fuel pump? Are those fairly easy to replace myself?

Also, I’m tempted to buy a new cat and install it... I’d hate to waste money and the smoke still be strong.
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tenders
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Buddy International 50 Italia

PostPosted: Thu Apr 04, 2019 11:09 pm    Post subject: Reply with quote

I think the point was that if what came out of the bolt hole wasn’t smoky, the problem is in the exhaust (catalytic converter) and not the engine.

You’re suggesting the pre-cat exhaust gases are smoky, thus, the issue is upstream of the cat. You suggested the smoke was present at startup, ie, when the engine is cold. For buildup on the cat to be the culprit, I would think the exhaust would have to take some time to get hot before the smoke started spewing.

If you want to be totally sure about this, as you mentioned, take the whole exhaust pipe off, plug your ears, start her up, and hope for the all-clear. It’s a couple of bolts on the side, and two nuts on the flange underneath the footplate, followed by some clever wiggling. You’ll have to get really creative to come up with a more efficient way to annoy your neighbors than running an unmuffled two-stroke engine in the neighborhood, especially if it’s gushing smoke. The police will eventually be called, or will show up on their own.

I’ll be more confident that it’s an oil problem if you confirm you’ve (1) checked the air filter and carb intake for general cleanliness and (2) tried to adjust the fuel/air mixture screw to no avail while she’s running. Even then, my money is 4:1 on an internal carb problem instead of an oil issue. I say this because partway during my carb travails two weekends ago, my drowning carb did manage to start several times and run 30 seconds spewing an unbelievable amount of smoke having nothing to do with the oil system. However, unlike your situation, it ran terribly - racing and barely responding to the throttle. Basically, I think the oil injection system is MUCH more robust than the carb so is much less likely to be the source of this.

AGAIN...if the scooter is running more-or-less normally and this smoke is the only issue, this situation is very close to being solved. Do not give up on it (and for the record, taking it to a mechanic with the diagnosis you’ve done so far is not giving up.) Worst case DIY scenario is probably a $175 carb as I don’t think the oil pump is that expensive.
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venmike
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buddy 50

PostPosted: Thu Apr 04, 2019 11:25 pm    Post subject: Reply with quote

Ok, I disnamntled the exhaust. It’s still smoking, so we know that it’s not the cat. Was really hoping that it was the cat! This stinks.
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venmike
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PostPosted: Thu Apr 04, 2019 11:39 pm    Post subject: Reply with quote

Air filter looked fine. How do I check carb intake?
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tenders
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Buddy International 50 Italia

PostPosted: Fri Apr 05, 2019 1:27 am    Post subject: Reply with quote

First, you look into it from the inside of the air box. It’s obviously in the left, forward corner. Hopefully you see a shop rag or a wasp’s nest or a calcified human finger or a torn corner of the foam air filter plugging it up and causing a rich condition.

Second, you might look at the seal of that rubber interface between the air box and the carb, on both sides of the air box. However, if there’s a leak, it would make the engine run lean or otherwise pretty badly and all this smoke is a sign of richness.

Next, I’d say you have four choices.
1- assume it’s the carb, replace the carb, see what happens. This process has been discussed here.
2- assume it’s the oil pump, replace the oil pump, see what happens.
3- disassemble the carb by removing the float bowl, and fiddle with the carb jets, passageways, needle valve, and float. My guess is it is not the jets since it runs so darn well. You do not need to remove the throttle stuff on the other side (top) of the carb. The other thing to inspect could be the choke with the wires coming off of it - that could be causing richness but I don’t know much about it.
4- take your findings to a mechanic and see what they do. My guess: they will do 1, 2, or 3 and charge you an hourly rate plus a markup on parts to do it. And would deserve every penny of it.

There might be option 5 if you can disassemble and inspect the oil injection system but that is out of my experience so far.

Personally I would do 3 and, assuming a perfectly clean carb interior and impeccably cleaned-up jets and passages, would inspect and probably replace the needle valve ($7), dress up the hole the needle valve goes into with a wooden chicken skewer sharpened to a point with a pencil sharpener, tweak the float hinge so the float rides 1/4” lower in the bowl after reassembly, and put it back together with a short prayer to St. Formosa, the patron saint of owners of slightly-misbehaving Taiwanese scooters.

If St. Formosa ignores those plaintive cries, I would decide if I’m feeling luckier with option 1 or 2. Me, I would start with 1 but do both if necessary before pursuing option 4 not because I am a cheap SOB (although I am) but because I genuinely like the satisfaction of solving mechanical puzzles like this. It is part of the fun of gas engines. And, if you have those specialized parts in hand when you go to the mechanic, he can confirm they are or are not the problem without waiting around to order them himself. Although a Genuine dealer might have them in stock.

If you do #3 make sure you choose the largest Phillips screwdriver you can get to fit into the carb bowl screws, and press very hard as you are removing them. They are not standard Phillips screws and will strip like a Vegas showgirl of you aren’t careful. (Same is true of the screws holding the cap of the front brake fluid reservoir.) I learned this sad lesson the hard way on my Vespa and replaced them all with high grade steel hex-drive fasteners.

Now, I am a dilettante with a very high tolerance for frustration, and I think Stanza is a pro, so consider that accordingly if he chimes in.


Last edited by tenders on Fri Apr 05, 2019 3:04 pm; edited 2 times in total
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venmike
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buddy 50

PostPosted: Fri Apr 05, 2019 12:48 pm    Post subject: Reply with quote

Thanks for all your help.
Here’s a video I uploaded to YouTube showing the issue.
Check it out and let me know what you think.

https://youtu.be/PBqzfbPVwOg
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Stanza
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PostPosted: Fri Apr 05, 2019 1:20 pm    Post subject: Reply with quote

venmike wrote:
Thanks for all your help.
Here’s a video I uploaded to YouTube showing the issue.
Check it out and let me know what you think.

https://youtu.be/PBqzfbPVwOg


That's definitely smoking more than a little.

Ok, two questions for you.

What kind of oil did you put in the tank? Brand, etc.

When you first start the bike up from a long sit, engine cold, does the idle speed change as it starts to warm up? If so, does it go from low to high, or from high to low?
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venmike
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PostPosted: Fri Apr 05, 2019 1:54 pm    Post subject: Reply with quote

I put in STP 2 cycle oil from my local Autozone.

On cold start the idle speed is the same. It had a very smooth idle. No surging. No signs of anything amiss. It’s solid, and runs great.
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tenders
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PostPosted: Fri Apr 05, 2019 2:37 pm    Post subject: Reply with quote

Stanza is wondering if the autochoke is working correctly. If it is, on initial cold startup it kicks in and richens the mixture going into the cylinder. The engine runs a little fast during this time - maybe a minute, 90 seconds. Once the engine is warmed up the autochoke shuts off, the mixture becomes leaner, and the idle RPM drops noticeably over a period of 5-10 seconds. Stanza is referring to this as “high to low.” This is why you set the air/fuel mix and idle RPM screws on a warmed-up engine.

I’m guessing here but his “low to high” scenario is one in which the autochoke is not kicking in at all. The carb has been set to run permanently rich to compensate for the fact that it won’t start at all when cold on the correct setting when warm. So it stumbles a little when it’s cold but the idle smooths out and increases as the engine gets warm. But, it’s rich, possibly very rich.

Both the workings and the superiority of the autochoke are mysterious to me. It is held in the carb with two small Phillips screws that secure a U-shaped bracket collaring the choke assembly, and once that is removed it pulls out of the carb with a friction fit due to some o-rings that seal it in. Once removed, it resembles a throttle needle that I guess moves up and down and meters extra fuel though a passage in the carb. It is wired into a harness with two wires (the connection of which is probably worth pulling apart, greasing a bit, and reinserting). How it senses temperature and how it moves the needle is not apparent. Why it is better than a manual choke you just pull out if starting is difficult and push in as with every other small engine I’ve ever owned is not apparent. Why you would spend $70 to replace it on a $170 carb is not apparent.

You weren’t clear after we exchanged PMs on the result of tweaking the air/fuel mix screw on the warm engine. That is the first line of defense with the mixture and could fully explain this juicy juicy level of smoke you’re putting out.
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Stanza
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PostPosted: Fri Apr 05, 2019 3:32 pm    Post subject: Reply with quote

Sorry for the long posts. I don't know how to condense this stuff into two sentence explanations....

Tenders is on the right track. I'll clarify a bit on the autochoke in a minute. But just getting the oil out of the way... STP 2 cycle is a very dirty burning oil, and not recommended for your bike. It's fine for a weedwhacker, chainsaw, snowblower, etc. But it's too messy for your bike.

Find a bottle of Motul, Ipone, Bel-Rey, etc. Something that's JASO-FD rated. Amazon it, if you must. What's happening, I suspect, is that this bike was previously filled with low grade oil from the previous owner, and you drained that out and replaced it with more low grade oil. As the pump only puts in about a drop every few seconds, once you replace the oil with something better, you still may have a mile or two of smokescreen to clear out before it comes clean.

Part two...
The autochoke is a mechanical plunger that contains a small heater. When you start the bike, this heater warms and expands a wax plunger, which pushes a brass needle out. Tenders, you've seen this when you took the autochoke off the carb. The carb has a fuel passage that lets a little extra fuel into the mix, which is then closed off by the brass needle once the autochoke heats up and the needle extends to block the passage. There's nothing electronic controlling it, or telling it when to turn on or off. It's a very simple heating circuit, which is calibrated to heat up and expand/extend at a set rate.

In warm weather, you probably won't notice it doing anything to the idle speed. But in cold weather, you will see the bike start off at a slightly LOWER idle speed, then come up to normal within a few seconds. This is because the engine is being given a slightly richer mixture, practically guaranteed to start. When it leans out (lean is mean), the rpms come up.

Now, if the autochoke is NOT working, then you could have a fuel mixture that is rich all the time. This would for sure make extra smoke, and smell pretty lousy. The easy way to tell if this is what's happening though, is to put a fresh spark plug in, and run it full blast for a mile or so. Pick a safe stretch of road, and while blasting, kill the engine via the switch on the handlebars. Coast to a stop, and pull the spark plug. You are looking for a medium brown, like faded brown leather shoes.

If the oil is nasty, the plug will be greyish black, like wet charcoal.
If the fuel mixture is too rich, aka autochoke problems or a mixture screw set wrong, the plug will be dark brown, like a dark dark chocolate.


TLDR....more to do. Don't lose hope!
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charlie55
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PostPosted: Fri Apr 05, 2019 4:18 pm    Post subject: Reply with quote

Everything you ever wanted to know about auto-chokes (bystarters)......

http://www.modernbuddy.com/forum/viewtopic.php?t=27646&highlight=bystarters

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tenders
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PostPosted: Fri Apr 05, 2019 4:18 pm    Post subject: Reply with quote

That is fascinating, Stanza, about both the cheap oil and the choke mechanics, thank you.

So the cold/de-energized state of the autochoke is “choke on,” and only when the engine starts and warms up does the heater actively turn the choke off. I think that is unnecessarily complicated compared to a manual choke, but maybe that’s part of what it takes for EPA certification of these inefficient small engines (both 2- and 4-stroke).

I am going to check on my Buddy tonight but I am pretty sure when cold that it starts with a consistently high idle and slows down after a minute or so. I have assumed that was the autochoke doing its thing but perhaps there is more going on, perhaps extra fuel hanging around from the cranking before the engine catches.
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Stanza
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Joined: 29 Jan 2018
Posts: 362
Location: Chicago
Puch Maxi, Honda C70

PostPosted: Fri Apr 05, 2019 5:16 pm    Post subject: Reply with quote

It is a little backwards, yes. A traditional choke reduces the amount of air available through the carb, whereas this is more of an auto-enrichment system, which increases the amount of fuel available
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charlie55
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Joined: 08 Apr 2008
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'06 Blur (Sold) '05 Honda Helix (Sold) '76 CB125S (Sold) '06 Honda Helix

PostPosted: Fri Apr 05, 2019 5:45 pm    Post subject: Reply with quote

Please refer to my post a couple of posts back. This topic has been raised so many times that I thought it a good idea to have a definitive discussion on the topic of bystarters. We were going to move it into the reference section, but I guess it got lost in the shuffle.
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tenders
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Joined: 03 Dec 2018
Posts: 87

Buddy International 50 Italia

PostPosted: Fri Apr 05, 2019 6:01 pm    Post subject: Reply with quote

That is great stuff, charlie55, thank you. I had not stumbled across it in my searches.
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venmike
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Joined: 02 Apr 2019
Posts: 16
Location: houston
buddy 50

PostPosted: Fri Apr 05, 2019 9:31 pm    Post subject: Reply with quote

The idle is higher when I initially start it. It gradually starts to even out after maybe 20 seconds, if that.

Would the oil that I used really cause this much smoke?? I understand it’s not the best quality motor oil, but can it really cause this lethal amount of smoke? I’ll order some ipone and see if it changes things..


Tenders, I’m still having trouble located this air fuel mixture dial you speak of. I’m not too mechanically inclined, but I’ve searched for this knob, and can’t seem to find it. Do I need to remove the seat?
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venmike
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Location: houston
buddy 50

PostPosted: Fri Apr 05, 2019 10:27 pm    Post subject: Reply with quote

Ok did some research found the knob you were referring to tenders. It did not alleviate the problem. Scooter still smokes like a chimney.

Tired of messing with it now.

I am likely going to sell it soon.

Thanks guys
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tenders
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Joined: 03 Dec 2018
Posts: 87

Buddy International 50 Italia

PostPosted: Fri Apr 05, 2019 10:31 pm    Post subject: Reply with quote

You don’t need to remove the seat but you do need to lift the seat to remove the plastic bucket/carrier under the seat to get at the carb. That’s two bolts towards the front, two towards the back near the gas cap, and take off the rubber cap covering the oil fill so it doesn’t get knocked off when you lift out the carrier.

Power tip: I replaced those carrier bolts with these thumbscrews for easier removal. If you stack two washers with each thumbscrew, the thumbscrew will stand proud enough up against the surrounding plastic to be able to grab comfortably when screwed in all the way.

https://www.amazon.com/gp/product/B00NQBQ4IM/

I prefer the Vespa design for the carrier - it just lifts out to expose the engine and carb, no fasteners to deal with. Most of the Buddy design is better than the Vespa, in my opinion.

Did you see my picture from Amazon in the PM showing the location of the fuel/air mix screw in relation to the idle speed thumbscrew?
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tenders
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Joined: 03 Dec 2018
Posts: 87

Buddy International 50 Italia

PostPosted: Fri Apr 05, 2019 10:48 pm    Post subject: Reply with quote

venmike wrote:
Ok did some research found the knob you were referring to tenders. It did not alleviate the problem. Scooter still smokes like a chimney.

Tired of messing with it now.

I am likely going to sell it soon.

Thanks guys


Sleep on it, don’t give up yet!

If you were messing with a knob, you had the wrong part. The knob, or thumbscrew, is the idle speed. The air/fuel mixture screw is NEXT TO the knob, more on the left side of the carb, and there is nothing knobby about it. It is a brass screw and either has a flat head, an obnoxious D-shaped head (most likely), or possibly no head at all for maximum annoyance.

If you did adjust the proper screw, and it made absolutely no difference in the smoke no matter what you did to it, a good case has been made that the oil is the issue. I would take five minutes to optimize the settings of the idle speed and the fuel/air mix screw (described elsewhere here), swap out the 2T oil one last time with the highest quality 2T oil you can find ($10), and put 50 miles on the odometer before deciding to sell it.
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venmike
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Location: houston
buddy 50

PostPosted: Fri Apr 05, 2019 11:31 pm    Post subject: Reply with quote

Yes. It wasn’t a knob. I used a flat head screw driver to adjust it. It would alter the idle, but the smoke stayed persistent regardless.

Ill Swap the oil one more time and report back. I really don’t think that’s causing the smoke, but I’ll do it just to give it a go.
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JJScoot
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PostPosted: Wed Apr 17, 2019 11:39 pm    Post subject: Reply with quote

Very interested to see if you had a chance to try new oil yet and the results.
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sc00ter
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Joined: 30 Mar 2008
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Location: Norfolk VA
19 Piaggio Liberty S, 98 Zuma

PostPosted: Thu Apr 18, 2019 2:05 pm    Post subject: Reply with quote

Was that electrical tape holding the emission hose onto the canister? If so, you have another issue causing this smoking issue. Fix the emission system correctly first if thats a "tape patch".
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