1970 Honda ATC90 Bog?

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Alright, so I was working on my 3 wheeler.

I learned that the bottom screw was for air, and the top screw was the idle.

Sweet, so that helps me.......not really. I'm not completely understanding of what to do in an instance of any issues, so I just play with things and end up breaking it worse.

Ok, now to the issue. I bought a brand new spark plug, because it wasn't starting, and now it starts easily, no issue's. But, when I go to go, I pop it into 1st and it just dies. So I set and screw with the carb jets hoping I can fix it.

The idle is fairly high, so I turn it down and it runs smooth at approximately 1300rpms on average. But when I hit the gas and open it wide, it either bogs really bad, or just dies.

I can't put the choke closed, because it dies. But if it's wide open, it runs but as listed above won't go.

When screwing with the carb I finally get it to go, but when I do get it to go, I can't get out of first gear because when I do, it bogs, and dies. Sometimes when I'm in first gear and I open it up, it dies also.

I'm a big guy and I consider this bike to not run very fast at all, but I expect it to be able to haul my heavy ass past 1st gear. It did last summer.

Any ideas of what to do? change? fix?

Help would be appreciated.

--Brett

[XL-erate]

There's several 'air bleeds' in the carburetor casting. These control fuel flow along with the venturi piston. When the air bleeds get clogged up the fuel feed signals get clogged up too. Looking close at carb throat and in jets you can see the air bleeds.

I'd suggest to start with a good soak in carb cleaner, then use a little wire like guitar string to clean out air bleeds. Flush it out with carb cleaner, blow it out with high pressure air and you should be good to go.

[re-lapse]

There's several 'air bleeds' in the carburetor casting. These control fuel flow along with the venturi piston. When the air bleeds get clogged up the fuel feed signals get clogged up too. Looking close at carb throat and in jets you can see the air bleeds.

I'd suggest to start with a good soak in carb cleaner, then use a little wire like guitar string to clean out air bleeds. Flush it out with carb cleaner, blow it out with high pressure air and you should be good to go.

Alright. I'll soak it, it's okay to soak it outside in the cold (probably 10 degrees Fahrenheit) right? Would it be okay to soak it in gas instead? I don't have any carb cleaner on hand. I have a guitar string that'll work good to.

Air bleeds are the tiny little holes, correct?

Sorry, I'm not very automotive savvy, but I'm trying my best.

[Vealmonkey]

You can go down to your local auto parts house and get a gallon can or carb cleaner. It will look like a paint can with a handle and inside, there will be a small immersible tray with a handle in it. Disassemble your carb and remove all the gaskets, paper and rubber and carefully remove the jets and the idle and air adjustment screws too, the jets are brass and can break easily. Make sure to remove your float check valve and float too. Soak all the parts but the gaskets and the float check valve in the carb cleaner over night. If the float is plastic, do not soak that over night. Just put the parts in the tray and the tray in the carb cleaner and put the lid back on the can and you can store in your house. Just don't spill alot of the carb cleaner or it will smell up the place. Also you can get a spray can or 2 of carb cleaner and once you take your carb out of the carb cleaner and dry it off with some paper towels or shop rags or old t shirts then you use the spray cans of carb cleaner to get in all the little holes as best you can with the little plastic straw provided on the can. Wear safety glasses cause sometimes the carb cleaner will spray out towards your eyes which is very painful and no fun. I personally never like using compressed air to blow out a carb but I guess that is personal preference. Dry the carb off again after you get all the old passageways sprayed out. If your gaskets are ok, reassemble your carb. I would recommend a carb rebuild kit but that will probably take a couple days for you to get, so it's up to you. 20 some year old gaskets and o rings could use replacing I'm sure and most good carb kits come with new jets, and all the gaskets and o rings and even a new float check valve too. Reassemble carefully, taking care not to break the brass jet by overtightening them and be careful with screws too as the metal is pot metal and pretty soft meaning it will strip easily. And start with your air screw about 1 1\2 turns out and your idle about 2 turns out and start it up and go from there. It usually will take several times of adjust the idle and the air fuel screw to get the carb dialed in. And whenever you turn the idle or air screw all the way shut, never ever tighten them down hard. It ruins the seat in the carb. If you have a carb that this has been done too, they rarely ever run right. Some people go through a couple carbs till they get a good one. And that's pretty much a carb rebuild.

[Vealmonkey]

If you are going to the trouble to rebuild the carb, you ought to look into new points and a new condenser while your at it. They aren't very expensive and a new plug would be nice too. Maybe an oil change while your at it. Also if I remember right there is an oil screen inside the engine clutch cover that should need cleaning. You should get the gasket for the clutch cover in case you mess your old gasket up taking off the clutch cover. Don't forget to dial in your clutch when you're done, too. I weigh over 200 pounds and ride atc70s, so your 90 will pull you around, it just needs some tlc and a good tune up.

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Okay, Thank you for the information, I appreciate it a lot.

I already did all of what you listed above, aside from soaking it. I used about a can of carb cleaner just cleaning it in every aspect though. Although probably not as thorough as it should have been, I thought it did well.

I did exactly that with the carb, I twisted the air jet about 1 and a half turns out. and the idle jet 2 turns out, completely worthless at those settings. The rpms are just WAY high.. and it bogs and quits.

I guess tinkering with it could make it run good again.

What are the reasons that it shifts so incredibly hard? If I'm not careful, it'll flip me off, and then it doesn't have enough power to hardly get through snow.... I'm not sure what to do to fix that.

=/

Thanks in advance.

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Alright so I was just outside workin' on the trike, I took the jets and I put them all the way in, and then pulled the idle out 32 clicks (aka 2 full turns) and I pulled the air jet out about 18 clicks (aka 1 and a quarter approx.)

Then I started it, it started instantly, better than most times. And the idle was sounding really good. So I hopped on and threw the throttle wide open, and it died.

Tried again, I got it going this time, but it took me almost 30 seconds toa ctually get going, cus everytime I gave it too much gas it bogged and almost died, .. then when I actually got it going when it was completely wide open, it died and yeah...

Any ideas? I feel that theres either too much gas, or not enough gas. But I'm not sure how to tel, or how to fix it, at that.
...

--Brett