Aftermarket Magneto

GoldenMotor.com

Huffydavidson

STREETRACER/MANUFACTURER
Jan 29, 2012
1,076
4
38
st.louis,mo.
This week I got two of the Screeming Roo magnetos and their NOT ANYMORE POWERFUL than what we have now infact metering them out the first one 336 ohms and the second one 340 ohms. However tested one of a "BeKit motor" came in at a WHOPING 347ohms. I email Jim Wilson with my test resuits and he was Greatful. We both agreed I'll ship them back with his next order from me. All good that Jim LOL
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
This week I got two of the Screeming Roo magnetos and their NOT ANYMORE POWERFUL than what we have now infact metering them out the first one 336 ohms and the second one 340 ohms. However tested one of a "BeKit motor" came in at a WHOPING 347ohms. I email Jim Wilson with my test resuits and he was Greatful. We both agreed I'll ship them back with his next order from me. All good that Jim LOL
Thanks for the info HuffyD, looks like more and more are getting into the CDI stuff, noticed Piston Bikes has something called Jet.... something cant remember now.
 
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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
In my teenage years I spent evenings working on cars and motorcycles instead of watching TV, that's my diploma.
I was the same way, when I was11 or 12 Id go to the city dump and drag an old beat up push mower to the house and many times Id have it fixed and running in a day or so, completely overhauled my first engine when I was just 12, my brother was watching TV and I was wrenching on something, fishing, or out in the woods with a rifle all year long, nothing wrong with reading a book but hands on experience by someone 2ho has a gift for understanding how things work is more valuable in my opinion.

sorry for vearing off topic here, just wanted to comment on what was said in this post since I can relate.

Now back to the spark plug snake oil topic....lol!
 

Huffydavidson

STREETRACER/MANUFACTURER
Jan 29, 2012
1,076
4
38
st.louis,mo.
MAP, it's Huffy or Huffydavidson not Huffed OK pal. One of the cdi he sells is a over priced Jag and the other one is from Gasbike.net s supercharged joke of acid. I bought one after MBR sent me text about it. All bad stroked_out @7000RPMs. I didn't test it myself, I loaded it to my Riding Crew here in st.louis,mo. BMW has it now testing it, then I'll send out to someone eles for testing. You want a turn ????
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
sorry about the typing error Huffy D, spell check on this tablet was the cause and I didn't catch it.

looks like you had the same glitch where you meant to type "loaned it to my Riding Crew" and it came out Loaded it to my Riding Crew....lol

I knew what you meant.

No foul intended Dan.

sounds like you having a good testing of the cdi going, sounds like another low performer in the high rpm catagory.
 

Huffydavidson

STREETRACER/MANUFACTURER
Jan 29, 2012
1,076
4
38
st.louis,mo.
Yeah its good Map. Just a call from Bert Rod the "Speed King of Miami" asking me to build one for him!!!! He said their running 28T sprockets down there and
kiss on 65mph. Holy Smokes Batman!!! Been to 51mph with the stroker fred built me last year and that scrared the .... ... out of me. Getting to old to be dancing with death, so I'll run anyone for a half mile after that I eaz up on it. Maybe going water-cooled KTM60 soon, of coarse with nothing but the BEST shiftkit
SBPs O'yeah boyz.shft.
 
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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Yeah its good Map. Just a call from Bert Rod the "Speed King of Miami" asking me to build one for him!!!! He said their running 28T sprockets down there and
kiss on 65mph. Holy Smokes Batman!!! Been to 51mph with the stroker fred built me last year and that scrared the .... ... out of me. Getting to old to be dancing with death, so I'll run anyone for a half mile after that I eaz up on it. Maybe going water-cooled KTM60 soon, of coarse with nothing but the BEST shiftkit
SBPs O'yeah boyz.shft.
oh Yeah That Bert Rod has got these HT 2 smokers screaming.

I've seen 52mph on one of mine and that was enough for me, Ive backed er down now and Im plenty happy to ruise at 40-43 MPH.

Just put a GT5 together last week and its doing 40-42mph with a 41T one the rear and its really smooth doing it, not my fastest bike but thats a good speed for me these days.

That KTM build sounds like it will be fun for you, just be safe on it for sure and start a thread on here when you get it started so some of us can watch it all ome together for you.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Bert Rod is freaking crazy, that man works magic on these motors.
yep he has made some very fast engines.

Not sure what all he does to them internally to get the power and rpms he does, but he sure ends up with a real screamer when he gets through with it for sure.
 

Rudz

New Member
Jun 24, 2014
454
1
0
Tyler TX
Seeing as nobody has posted posted a ride checked by radar proving they're faster than his builds, he currently owns the crown. I believe the current record this week is 65mph
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
It's one thing to set record speeds, they do it all the time the NHRA dragsters, but have to rebuild the entire engine between every run.

Race or ride reliably with little maintenance effort, it's a fine line between the two.
 
Jan 21, 2015
610
25
18
Portland, Oregon
Well, I can now confirm that the newer magnetos with no white wires are much better. I bought three after reading people's speculation about differences, one for the bike, one for backup, and one to pull apart and compare with the old one. I found several things: They have thicker wires, better connections, better (and by this I mean less sloppy) coil wrapping, better (this time actually pretty decent) soldering job, and make a very strong spark. I am getting a very powerful spark, clearly visible in direct sunlight, with a gap of .032 and a $4 NGK spark plug, enough that the motor runs noticeably better. Also, in terms of getting the magneto spaced correctly, I found that you can tear strips of paper, put two or three strips around the magnet on either side, and slide them out after bolting down the coil.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Well, I can now confirm that the newer magnetos with no white wires are much better. I bought three after reading people's speculation about differences, one for the bike, one for backup, and one to pull apart and compare with the old one. I found several things: They have thicker wires, better connections, better (and by this I mean less sloppy) coil wrapping, better (this time actually pretty decent) soldering job, and make a very strong spark. I am getting a very powerful spark, clearly visible in direct sunlight, with a gap of .032 and a $4 NGK spark plug, enough that the motor runs noticeably better. Also, in terms of getting the magneto spaced correctly, I found that you can tear strips of paper, put two or three strips around the magnet on either side, and slide them out after bolting down the coil.
Thanks for the info on this, good to know that at least some of the newer ones are being put together a little better, I need a couple of spares myself so those are the ones I'll get.

Would you care to share a link to where you found yours?
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Well, I can now confirm that the newer magnetos with no white wires are much better.
Yep, the same size mag, but throwing out the useless secondary coil winding they had more room to use thicker wire and more of it.

I am getting a very powerful spark, clearly visible in direct sunlight, with a gap of .032 and a $4 NGK spark plug, enough that the motor runs noticeably better.
Yep, though part of the boost is because the NGK's are a tad longer than stock so you get a bit of compression boost, a big nice spark is what is important.

I go a couple steps further on my builds.

Besides using the Iridium version of the NGK plug I cut the stock wiring off at the mag and use some nice double insulated very flexible 16G wire from the magneto up to the CDI.



Note the black ground wire from the bottom terminal that solders to the mag base, that is your spark plug ground.

Then I just route the wire away from exhaust to where I want it, stagger cut the CDI wires and kill button wires and connect all 3 up right there on the CDI.



Then just glue on a plastic hobby box cover, sometimes with a keylock switch that is just a kill button, you just need the key to operate it.




Also, in terms of getting the magneto spaced correctly, I found that you can tear strips of paper, put two or three strips around the magnet on either side, and slide them out after bolting down the coil.
Good tip, I use a sliver of file folder paper, about the same width but just one piece.
The point of course is you need an equal air between the magnet and mag bars.

One more tip...
You have to fight that magnet to get the magneto mounted, if it's easy you have a weak magnet, rare but I have seen it.

Everything tests fine but still no spark.
Everything starts with the spinning magnets ability to generate a current in the coil.
Crap magnet = crap current.
 
Jan 21, 2015
610
25
18
Portland, Oregon
Thanks for the info on this, good to know that at least some of the newer ones are being put together a little better, I need a couple of spares myself so those are the ones I'll get.

Would you care to share a link to where you found yours?
Just go on ebay, look up "motorized bicycle magneto" find a picture of one with no white wires, and contact the seller to make sure and specify that if it has a white wire, you don't want it. There are a bunch of sellers.
 

fatdaddy

New Member
May 4, 2011
1,516
4
0
San Jose, Ca.
Hey Necro, The thing is there are also a lot of manufacturers, Not all are equal. What we're looking for is who YOU got yours from so we stand a better chance of getting one thats put together right.
fatdaddy.usflg
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
I am using these, they come in all the new kits.
http://www.gasbike.net/sparker-wire-magneto.html



$10.

Note that picture is upside down, why I have no clue, it mounts flipped over with the blue wire on top.

They did beef up the wire gauge some, 18 maybe, the old ones were little 22's or so, it makes no diff to me as I run beefy 16 but better none the less.
 
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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Thanks KC,

After doing some searching I have found multiple vendors who have these newer type mags, they just look better overall, some of the older ones I've had and seen look like that got drug behind a truck before they were install on an engine...!

thanks for the info.