Ok, I'm at a freakin, loss!

Grubee GT2 48cc
SBP Ex. Chamber
Dax RT Carb
Boost
NGK Sparkplug
32:1
800 ft. elev.

Ok, that's the bike.

Here's the problem:

Lost power/spark.

Changed:

Brand new CDI, cut white wire completely, and all solders/grounds look good.
Not wet. Scuffed back-side of Magneto Frame/Ground.

Upgraded wire from CDI to Plug, wire correctly.

NGK Plug brand new.

Brand new magneto installed, and woodruff pin in place on magnet.

Seals good, no air leaks anywhere.

Checked on the gear side, pulled gear, gear in tact, no seal leak. Re-installed, nice n tight.

Wired correctly. No KILL switch attached, blue wire only!

ZERO spark!

HELP!

WTF?

Thanks.

PS: Bike ran great for about 350 miles prior to this.

Chris B.

Al.Fisherman said:

Just because parts are new doesn't mean they are good. Like said, check magneto output. Check compression.

Click to expand...

Compression good (finger in the sparkplug hole test).

Sucks and blows strong.

Don't have the tools for ohm testing yet.

Will pick up.

What type/range of meter should I get?

~Chris B.

Hey Drewd,

I'm testing for spark with plug out of jug, and laying on the fins, and ZERO.

I just did a complet OHM check and here are my results, compared to a recent post with suggested readings.

Thought?

See below:

Hey there, based upon a former post, I've included my results here on my 48cc GT 2, with ZERO spark, and would love your preliminary analysis. Thanks in advance for your time!

New CDI, new Magneto, New Spark plug, Upgraded cable. I CUT off the white wire connection completely ON the coil, although there's still a 'nub' to connect to for testing.

Woodruff key in place (superglue), Varnish/Contact points all scuffed.

Ok, so following your recent suggestions, here are my answers with my new Multimeter, step by step.

Use Low Ohm-Meter Scale About 200 Ohms

Magneto Coil

1) Check Ohms between BLACK wire and WHITE wire. Reading should be around 2 Ohms (3.3)
2) Check ohms between BLUE wire and WHITE wire. Should be around 300-400 ohms. (ZERO reading at 200 ohms setting, BUT, at 2M setting, I get 0.001)

CDI

Use Ohm Meter High Scale About 200-K
1) Positive lead on BLUE wire and Negative lead on BLACK wire should read infinite (no activity) I get 0.4.
2) Positive lead on BLACK wire and Negative lead on BLUE wire. Should be about 130-150 K-ohms I've got 0.3.
3) Positive lead on Spark Plug wire and negative lead on BLUE wire. Should read between 135-155 K-ohms. I've got 10.2.

Switch to Low Scale 20K
4) Measure between Spark Plug wire and Black lead. Should be about 2.5 - 2.7 K- ohms I get 9.7.

So, I get zero spark, if not MAYBE a minor spark here and there but technically zero.

Was running great for the last 300 miles.

Thoughts?

Thanks much!

Chris B.