Moped runs without spark cap

Recently I have instaled a 70cc performance kit from treatland. And it is making a loud high pitch engine noise if you go past 20mph, I’m not sure if I messed up the break in period or something but would anyone have an idea how to fix this? Also, the engine continues to run even though the ignition is off and it continues to run when I take the spark plug cap off the spark plug, there is clearly electricity running through the bike but I have no idea what to do to fix this, would anyone have any ideas how to trouble shoot this or anything please let me know

Re: Moped runs without spark cap

Chöschi21 C.K. /

No Electricity, Your engine is Screaming for help, running either to hot, having faaaar to much Ignition timing or faaar to much compression, it's self igniting without a Spark, not good for the Engine and it's Internals. How big is your Squishgap, how big is your Combustion Chamber, what's timing set to and what gas are you running?

Re: Moped runs without spark cap

LOL!!!!! You're engine is VERY hot causing pre ignition. You need to set your timing and get your squish right.

Re: Moped runs without spark cap

Overpriced Parts /

I kinda think it’s a fake video because it wasn’t fake soon as you touch that spark plug wire if you would get set on your ass but if not fake it’s what Stephen said

Re: Moped runs without spark cap

> Ken Roff Wrote:

> -------------------------------------------------------

> I kinda think it’s a fake video because it wasn’t fake soon as you touch

> that spark plug wire if you would get set on your ass but if not fake

> it’s what Stephen said

He did turn the key off before he pulled the wire I think. I was thinking the same thing you said at first until I watched it again.

Re: Moped runs without spark cap

leave it, its cool.

Re: Moped runs without spark cap

Huge air leak, poor tuning, bad timing, hung throttle slide, all of the above.

Re: Moped runs without spark cap

Dieseling, less compression, timing, higher octane gas or a combination of all 3

Re: Moped runs without spark cap

Re: Moped runs without spark cap

I read in a blog somewhere that your engine can sometimes run on just compression and compression can cause the fuel to ignite. I'm not sure if that's applicable to the compression of a moped thou.

Re: Moped runs without spark cap

> kenny s Wrote:

> -------------------------------------------------------

> I read in a blog somewhere that your engine can sometimes run on just

> compression and compression can cause the fuel to ignite. I'm not sure

> if that's applicable to the compression of a moped thou.

Yes,that's how a diesel runs. Gasoliine ignites even more easily on high compression and faulty timing.

Re: Moped runs without spark cap

Hey Stephen, the igition timing is set to .015 mm is the gap, and I’m running regular 50:1 gasoline mixture, I suspect I have way too much compression since my cylinder head needs two gaskets or else the piston will hit the head, anyone know any good cylinder kits?

Re: Moped runs without spark cap

> Luc Bordier Wrote:

> -------------------------------------------------------

> Hey Stephen, the igition timing is set to .015 mm is the gap, and I’m

> running regular 50:1 gasoline mixture, I suspect I have way too much

> compression since my cylinder head needs two gaskets or else the piston

> will hit the head, anyone know any good cylinder kits?

.015mm is the gap? Is that the spark plug or points gap?

Re: Moped runs without spark cap

Get a 1mm base spacer and use 2 gaskets.

Re: Moped runs without spark cap

> Daniel '' Wrote:

> -------------------------------------------------------

> Get a 1mm base spacer and use 2 gaskets.

^^^^^ this. You want to see space the cylinder not the head.

Re: Moped runs without spark cap

Dirty30 Dillon /

I bet you lost the crank case drain screw seal on the bottom of the engine.

Air leak for sure

Re: Moped runs without spark cap

That’s some good dieseling!

Just lower the compression and up be fine?

What kit?

Re: Moped runs without spark cap

> Luc Bordier Wrote:

> -------------------------------------------------------

> ... the ignition timing is set to .015 mm is the gap, and I’m

> running regular 50:1 gasoline mixture, I suspect I have way too

> much compression...

I suspect you are mixing up imperial measurements with metric. What you want your points gap to be is 0.015in. Your stated 0.015mm converts to 0.0006in. This will NOT work. Please recheck your points gap and ignition timing. Remember: Set the gap FIRST then set the timing. If you insist on using metric for setting the points gap then you are looking for 0.38mm. Do you have a 0.38mm feeler gauge?

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