Tomos A3 carb adjustment

I am working on a Tomos A3. It has the Encarwi carb on it. How can you adjust the mixture? Is changing the jet the only way. This thing is frying the plugs after driving 10-20 miles. Would a hotter rated plug help? Thanks!

Re: Tomos A3 carb adjustment

Don Pflueger /

all you can do is change the jet. use a champion l86c. what mods have been done on this engine?

Re: Tomos A3 carb adjustment

Woohoo. A good ole Encarwi. Sounds like the plug. I'd do as donp said, and get a Champion L86C. I've found them the best to work in my A-3's. The jet size should be either 50 or 46, depending on the year of ped it came out of. And yes, that is the only way to adjust the mixture on those carbs.

Re: Tomos A3 carb adjustment

Don Pflueger /

i say his exhaust is plugged up. but i want to know what mods he has first.

Re: Tomos A3 carb adjustment

Thanks for the reply. I was out of town yesterday. This is a stock bike with only 700 miles on it. I will have to check the jet size. I pulled the baffle and cleaned it and then heated the pipe to get what little carbon out that was left. I suspect that the crank seals are dried causing too much air to get in? I have heard that was common on these. Is that correct? Thanks!

Re: Tomos A3 carb adjustment

Don Pflueger /

when a crankseal goes bad, the engine usually will not idle at all if it will even run.

Re: Tomos A3 carb adjustment

Any idea what might be causing it? The jet size must have been o.k. when it was new. I am reluctant to change the jet or plug because of some other problem that I am not addressing. Thanks!

Re: Tomos A3 carb adjustment

Don Pflueger /

have you cleaned the exhaust port and piston top as well as the cylinder head?

Re: Tomos A3 carb adjustment

I did clean the exhaust port when I did the entire exhaust. It was not bad at all with only 700 miles of use. Could the lean condition be caused by carbon buildup? Thanks Don

Re: Tomos A3 carb adjustment

Don Pflueger /

lean conditions are caused by;

plugged gas cap vent

plugged or dirty petcock screen

plugged or dirty petcock

restriction in the fuel line

dirty carb

missing or improperly connect air box

too small of a main jet (doubt it in this case)

restriction in the intake

air leak at intake to cylinder

missing or loose oil banjo (only on oil injected models)

air leak at head gasket

air leak at cylinder base gasket

crank seal leak

exhaust flange gasket leak

missing exhaust

exhaust that has been modified without upjetting carb

baffle tube in exhaust missing or modified without upjetting carb

port timing altered (doubtful in this case since you say the engine is stock)

Re: Tomos A3 carb adjustment

Wow, I have got some homework to do. Thanks for the input!!

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