Pap Pap Pap

SteelToad /

I still don't think I have the carb set right, and I may have another problem. I

could really use some suggestions. 2000 70cc Sprint w/ BiTurbo & 27th sprocket.


- Oil residue at the end of the BiTurbo, even after a 10 mile ride.

- Idle is a little fast, when I set it down some, it's a guessing game

if it is going to stay running later.

- When I wind it all the way up and then let off the gas, I get a pap-pap-pap from

the exhaust, and it seems like the motor doesnt want to slow down.

- Exhaust smells a little gassy.

- Runs good, But I seem to run out of acceleration at the top end (duh)

Re: Poppity Pop Pop

This is not your fathers Buick!

Its a two stroke.

...Never... ever.... worry about spooge at the end of the pipe on a two stroke.

I would worry if I saw NO oil.

It shows you that you are getting lubrication.

And they always make poppity pop sounds off throttle on decel.

The only thing that is really important is the plug color after a half mile long honk at wide open throttle... Stop on the spot and pull the plug and check the color and report back here.

Then we will know whether you are rich or lean or what.

The only other thing you are talking about here is the idle settings.

And since I am not specifically familiar with your model....

I can just say to keep fiddling with the (2?) idle screws (mixture and speed).

Check where they are by screwing them in all the way while counting eighths or quarters of a turn for a frame of reference.

Keep fiddling till you are happy.

Re: Poppity Pop Pop

SteelToad /

I'll report back the plug color this evening if it isn't raining when I get home. I wish

I could ride it back and forth to work, but I don't think it would be that fun on

a 90 mile round trip.

How long (distance) can you push a ped on a continuous ride before you start

to hurt it.

BTW: Your right, it is more of a Poppity-pop-pop and not pap-pap-pap :-)

Re: Poppity Pop Pop

Ron Brown /

I expect to ride to the MA Barbeque this spring, 100 miles one way, but I don't know any reason you can't go as far as your butt can stand.


Re: Poppity Pop Pop

Reeperette /

>>How long (distance) can you push a ped on a continuous ride before you start

to hurt it.<<

A long, long, loooooong time.

Believe it...I would tell ya how I know that, but you'd prolly not believe me.


Re: Poppity Pop Pop

you might not be able to push that 70cc kit for that long. i have heard they seez up at top speeed. might wnat to take it easy on it

Re: Poppity Pop Pop

SteelToad /

Ok, I thought the wether was going to totally suck today, but it cleared up

nicely on my way home, and I got a chance to get on the bike for a much needed


After riding around for a while to get warmed up, I ran it wide open for a mile

(that was fun in itself). I stopped and took out the plug. It probably took me all of

thirty seconds to shut off the bike, get off, put down the stand, and get the plug


I was pleasantly suprised to see no oil or junk on the plug at all, maybe just a

slight oil film on the thread area. The color was black, just like the plug was

fresh out of the box.(not dirty). There was no color glow of any kind. In fact I could

hold my finger on the tip for about 10-15 seconds before I could feel it heating my

finger tip. It was about 60 degrees, so my fingers weren't cold.

What does that tell you ???

Re: Poppity Pop Pop

OK... We have a little confusion here.

We are not looking for the color of any metal part of the plug.

The color we are looking for is the color of the ceramic inside the plug....the part of the plug inside of the metal threaded portion of the plug... on a brand new, never used plug it is refrigerator white.

As it runs it should color up from pure white to some shade of tan or light brown.

No part of the plug ceramic on a decent running engine should be black.

No part of the plug ceramic should be "glowing".

And the key is not to pull it out in a big hurry before it cools off.

The key is to shut the engine off as soon as possible after the full throttle run so that idle carburetion mixture doesn't leave a color different from the wide open color.

In other words... run it hard......... get on the brakes and KILL the motor... no idling!.

You can now let it sit for a month if you want (without running) and pull the plug and see how it was running while you were flogging it.

Try it again... Unless you remember the color of the ceramic.

I also want to know how old the plug is.

Re: Poppity Pop Pop

I have a friend from Italy and she tells me that on long trips they would run peds for only about half an hour at full throttle and then either take a little break (there

Re: Poppity Pop Pop

SteelToad /

Damn, you mean I gotta ride it again, Oh mannn :-)

Ok, I'll give it another try looking at the ceramic this time. I can't really say that

I remember all that well. I was just happy not to see oil or junk on the plug.

The bike and the plug are both only 3 months (400+) miles old. Thanx

Re: Poppity Pop Pop

SteelToad /

Well, I learned just how fast I can brake and turn off the engine today, much

faster than I thought

The color was kind of hard to describe. It's sort of a dark cinamon color, sort of

brownish, with just a hint of orangeish. Sorry I can't describe it better.

Re: Poppity Pop Pop

Brandon E /

Would you say it's golden brown? If so, that's the color you want. Just as long as it's not light tan or white.

Re: Poppity Pop Pop

Ron Brown /

You sound like an interior decorator! But your plug color sounds ok. :-)


Re: Poppity Pop Pop

Sounds pretty good... It can get to tan and be alright.

I like it a little darker than tan or cinnamon (after wide open throttle).

As the weather gets warmer it will go farther away from white.

If it starts to go to real dark brown and wet looking... You could probably go one step leaner on the main... But it doesn't sound like you need to.

And anytime you make any change you should check it again.

Going white means danger of a piston seizure (not good!)

Re: Poppity Pop Pop

SteelToad /

Thanx for the diagnosis, and I'm glad to hear you think it sounds ok.

Just out of curiosity, what causes the color change. Is it just deposits being burnt

on or off of the ceramic. If so, is the white ash-like residue, or what ? Brown and

wet looking, I could understand. My plug was anything but wet, nice and dry and

clean. I would love to see a spark plug come out of any car I have ever owned

looking that clean.

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