My Hardly 'Dere-ison

[ahdunno]

My first build, it went pretty well thanks to you folks here! Started with a Schwinn Clairmont that I picked up for $50 off of Craigslist. Added a Boy Go Fast RB80 Black kit.
It didn't run good to start with. Found out the gasket inside the petcock wasn't located correctly and it was starving for fuel. Repositioned the gasket and it runs great.

 

[ahdunno]

Kill Switch Mod
I've read the horror stories about wiring the stock kill switch to the Blue and Black wires.
Here's what I did. I removed the silicone/(hot glue?) from the throttle housing where the switch was. Pic 1 shows the stock switch. Notice the 3 poles (Crappy cell phone pics). The red wire (middle pole) is common. The black wire is furthest from the plunger and is a closed circuit when the button is pushed. I moved the black wire to the pole closest to the plunger (Pic 2). That makes it a closed circuit in the button's relaxed position. I then connected one wire to the Black CDI wire and the other to the Black magneto wire. When the button is pushed ot opens the circuit and kills the motor. Works great!

 

[biknut]

Kill Switch Mod
I've read the horror stories about wiring the stock kill switch to the Blue and Black wires.
Here's what I did. I removed the silicone/(hot glue?) from the throttle housing where the switch was. Pic 1 shows the stock switch. Notice the 3 poles (Crappy cell phone pics). The red wire (middle pole) is common. The black wire is furthest from the plunger and is a closed circuit when the button is pushed. I moved the black wire to the pole closest to the plunger (Pic 2). That makes it a closed circuit in the button's relaxed position. I then connected one wire to the Black CDI wire and the other to the Black magneto wire. When the button is pushed ot opens the circuit and kills the motor. Works great!

So that's a stock switch that you modified?

At any rate, good work. I had 3 magneto coils burn up this year in the hottest part of the summer. After unhooking the kill switch I haven't had a failure since. I would never use a stock kill switch again unless it worked the way yours does now. That's how they should have done it in the first place.

 

[ahdunno]

Yep.. Stock switch. Just move one wire and you're good to stop!

 

[biknut]

Yep.. Stock switch. Just move one wire and you're good to stop!

I did take mine apart, and I ran all over town looking for a normally closed switch to replace it with. I can't believe I didn't think of doing that. I'm going go back and see if mine is like the one you have.

The way the stock switch works by shorting the coil is definitely not a good way to do it. I ended up buying a kill switch from SBP that is a rocker switch that I wired the same as yours. It works great, but the button isn't as convenient because it's farther away from your thumb.

 

[ahdunno]

Yeah, I read where someone was using a toggle switch but I wanted the convenience and functionality of the thumb button.


I think Fatdaddy posted about the old lawnmower engines used a piece of spring steel to ground the spark plug out at the cap. I tried wiring one wire to the spark plug wire and the other to a ground on the engine but it didn't work. So, some head scratching later I thought to look into rewiring the stock switch. It was just a stroke of luck to find the 3rd pole already existed on my switch. Luvin' it.

 

[biknut]

I just checked my stock kill switch, and no dice for me. Mine only has 2 terminals and the switch looks a little different for yours.

You got the right idea though. Your magneto will last a lot longer the way you wired it.

 

[ahdunno]

Now that you know what to look for, maybe you can find a 3 pole switch instead of one that is normally a closed circuit. If I stumble on one I'll PM you and post it as well.

 

[biknut]

Now that you know what to look for, maybe you can find a 3 pole switch instead of one that is normally a closed circuit. If I stumble on one I'll PM you and post it as well.

Thanks for that. Where did you get your kit, and do you know who made it?

Sorry I just noticed it's BGF.

I'll my other ones, I have at least 3 of them.

 

[ahdunno]

This looks like it, 20 cent item. You'd have to check the dimensions against those of your existing switch.
http://www.surplus-electronics-sales.com/index.php?main_page=product_info&cPath=53&products_id=463

 

[biknut]

None of mine were BGF Red Bat. I'll check their web store for throttles though.

 

[ahdunno]

Check my last post and your PM. This might work:
http://www.surplus-electronics-sales.com/index.php?main_page=product_info&cPath=53&products_id=463

Use Google Images and search for 3 pole push button switch. You might see a replacement that looks similar to yours.

 

[biknut]

Check my last post and your PM. This might work:
http://www.surplus-electronics-sales.com/index.php?main_page=product_info&cPath=53&products_id=463

Thanks a lot. I'm going to check that out.

 

[biknut]

So how are liking you Red Bat motor. I haven't seen anyone talking about one.

I've bought 3 motors from BGF. A X80, T80, and a Z80. All three were crappy.

 

[ahdunno]

Radio Shack has these also. Probably could be finagled. 4 pack for $3.69.
http://www.radioshack.com/product/index.jsp?productId=2062540

 

[ahdunno]

So how are liking you Red Bat motor. I haven't seen anyone talking about one.

I've bought 3 motors from BGF. A X80, T80, and a Z80. All three were crappy.

So far so good. I haven't done any long runs yet but it seems to run hot. Problem is, I have no experience with these motors to know how hot is too hot.

Fatdaddy let me in on some head gasket info. There are thick ones and thin ones used on the new slant head motors. The thin ones have higher compression and more heat and you need to double 'em up or get the thick one. I ordered a gasket kit so I could double up if need be. My newbie mistake was that I didn't know that there are 6mm and 8mm head bolts. The extra gasket was 8mm and my motor is 6mm. I need to get a 6mm gasket and a torque wrench and I'll add it. Next payday can't come soon enough!

 

[biknut]

If there's a Harbor Freight near you they have a good 1/4" drive inch lb torque wrench that only costs about $15. I have one that I use for my head bolts, and it works real good. I torque them to 125 in lb. You need to retorque them about 4 or 5 times the first 100 miles or so. After that not so often.

 

[ahdunno]

Yeah, I get the emails and saw the 1/4 incher for $15. There's coupons available for the 3/8 for $10. People are selling the coupons on ebay. One seller forgot to block out the UPC on his pic and I grabbed that. Coupon disclaimer says it requires "original" coupon. I'm going to try it anyways and if its rejected I'll probably get the 1/4 one.

For right now, after I ride I just throw a wrench on them and make sure they haven't loosened up.

 

[biknut]

Yeah, I get the emails and saw the 1/4 incher for $15. There's coupons available for the 3/8 for $10. People are selling the coupons on ebay. One seller forgot to block out the UPC on his pic and I grabbed that. Coupon disclaimer says it requires "original" coupon. I'm going to try it anyways and if its rejected I'll probably get the 1/4 one.

For right now, after I ride I just throw a wrench on them and make sure they haven't loosened up.

I have the 3/8" one too. It's in foot lb which is usually to much for most of the stuff on a mb. I did use it the other night to torque my hub adapter to 20 ft lb though.

If you only get one, get the in lb one first.

 

[dracothered]

Now that you know what to look for, maybe you can find a 3 pole switch instead of one that is normally a closed circuit. If I stumble on one I'll PM you and post it as well.

The type of switch that is in there is called a single pole, double throw switch (SPDT Switch). They come in latching and momentary styles. Latching is you push the button and it latches in that position and then push the button it goes back to the original state. The momentary is where it changes state when you push the button, but changes back as soon as you release the button. Of course there is also toggle switches like this that works the same way.