Drill test voltage?

Trying to “find my spark” on a Vespa Bravo. I’ve pulled the lighting coil / just have the ignition coil in place right now (it’s internally grounded/ does not go to a brake light circuit) . I’ve measured resistance/ohms on the ignition coil and it sits right around 1ohm.

When spinning the flywheel/crank with a drill, I measure right about 1v. Could the magneto / coil be throwing low voltage because of low RPMs by the drill? If I put the motor back in and pedal, will I be able to read higher voltage 6v?

Re: Drill test voltage?

Bump for the morning crowd

Re: Drill test voltage?

> Jimmy John Wrote:

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

> Trying to “find my spark” on a Vespa Bravo. I’ve pulled the lighting

> coil / just have the ignition coil in place right now (it’s internally

> grounded/ does not go to a brake light circuit) . I’ve measured

> resistance/ohms on the ignition coil and it sits right around 1ohm.

>

> When spinning the flywheel/crank with a drill, I measure right about 1v.

> Could the magneto / coil be throwing low voltage because of low RPMs by

> the drill? If I put the motor back in and pedal, will I be able to read

> higher voltage 6v?

That doesn't make much sense, how much faster would you really spin the motor by pedalling it as opposed to using the drill? Try to clean the points first and foremost before you dive into more advanced stuff. The 1 ohm resistance is about right though.

Re: Drill test voltage?

Indeed - clean the points - with brake cleaner and a fine tooth file. Carb cleaner eaves a carrier behind and any abrasive paper or cloth can leave grit behind to kill the contact and spark.

Check that your condenser is in goodly condition.

Re: Drill test voltage?

Brand new points and condenser from Treats are installed.

I’m thinking the drill spins the cam and flywheel at around 800rpm.... wouldnt pedaling be closer to 2k or so rpm?

Re: Drill test voltage?

I would clean those points anyhow, new or not.

Re: Drill test voltage?

> Rebel Moby Wrote:

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

> I would clean those points anyhow, new or not.

That^ . It only takes a finger print to fowl points .

Re: Drill test voltage?

Hey

Re: Drill test voltage?

Allllrighty. I’ll give the points a good cleaning tonight and see if that changes anything. Will report back later tonight.

Re: Drill test voltage?

Some drills can’t spin fast enough for a cdi system to work, I don’t know for points though.

Re: Drill test voltage?

> Annice Hernandez Wrote:

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

> Hi guys, can someone help me?

Spammer ?

Re: Drill test voltage?

No - just a troll to give you a link to the Russian casino

> P D Wrote:

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

> > Annice Hernandez Wrote:

>

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

>

> > Hi guys, can someone help me?

>

> Spammer ?

Re: Drill test voltage?

Troll ? That's much worse than simple spam . ;)

Re: Drill test voltage?

We should all send “her” a pms!

Re: Drill test voltage?

Finally got some time to work on it again.

Cleaned/ lightly sanded the points as suggested. Spun it up with the drill again... but still only reading 1v.

Got pretty frustrated, and decided to hook up the ignition coil / spark plug to see what would happen. Spun it again, and lo and behold I have spark. It’s not a big fat blue spark, but it’ll jump the plug gap, and would also jump about a 1 inch gap from the end of the plug to the case.

Planning on putting the engine back in the bike and seeing if it’ll start up with pedaling.

Re: Drill test voltage?

> Jimmy John Wrote:

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

> Finally got some time to work on it again.

>

> Cleaned/ lightly sanded the points as suggested. Spun it up with the

> drill again... but still only reading 1v.

>

> Got pretty frustrated, and decided to hook up the ignition coil / spark

> plug to see what would happen. Spun it again, and lo and behold I have

> spark. It’s not a big fat blue spark, but it’ll jump the plug gap, and

> would also jump about a 1 inch gap from the end of the plug to the case.

>

> Planning on putting the engine back in the bike and seeing if it’ll

> start up with pedaling.

You need a good fat hot blue spark my friend especially on points. Cdis will not give you a big spark but it’s a fucking sharp one a will like make a snapping noise.

A lot of stuff can cause a bad spark. Bad points, bad primary or secondary coil, bad flywheel, bad wires or connections , bad spark plug wire and or boot, bad spark plug , bad ground

Re: Drill test voltage?

Got the engine mounted and pedaled the bike. Made sure to hook a multimeter up to the wire that feeds the ignition pack, and with great delight can report that the meter was reading 6v.

Lesson learned is that rpms are correlated to voltage output. My drill could only spin the flywheel fast enough to generate 1v. When pedaling the bike, the flywheel spins fast enough to produce 6v.

I’m confident I’ll have a big fat blue spark when I hook up my ignition pack and new plug!

Re: Drill test voltage?

> Jimmy John Wrote:

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

> Got the engine mounted and pedaled the bike. Made sure to hook a

> multimeter up to the wire that feeds the ignition pack, and with great

> delight can report that the meter was reading 6v.

>

> Lesson learned is that rpms are correlated to voltage output. My drill

> could only spin the flywheel fast enough to generate 1v. When pedaling

> the bike, the flywheel spins fast enough to produce 6v.

>

> I’m confident I’ll have a big fat blue spark when I hook up my ignition

> pack and new plug!

Yea the same thing happens with the Treats CDI and it’s an absolute bitch to find where it’s firing with a drill and a timing light. I can get it to barley spark with the drill wide-open and because the timing advances with Rpm the timing is retarted when using a drill.

When you think something is broken but it’s actually just being tested wrong.

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