HELP! Race mower progress thread

[LAWN BOY]

I’ve been in the slow process of building a speed mower for a while now. I will do a 2 inch pulley swap on the transmission. I received a Craftsman LT and it’s 12hp tecumseh single needs lots of work. I took its deck off and found a donor tractor, MTD Yard Machines, no deck, good running Briggs and Stratton 13.5hp PowerBuilt. Got the new motor in the Craftsman today. I dislike wiring and am not good at it. I’ve done motor swaps before but not with such an age difference in motors or wiring that I can recall. The simple answer would be to swap all the wiring over, but the donor tractor has wiring connected to the ignition wiring that goes to the brake pedal for safety. I dislike that safety feature and don’t want to mess with more wiring than I have to. Do I have the ignition coil wire set up right for the boot to go on and all? How do I bypass the brake wiring? Or what should I do? Any help would be greatly appreciated as I no longer have my dad or neighbor to help me sadly. Thanks for your time.

 

[dall]

@redline4 your son is in need

 

[EFSM]

As for the coil wire, the inner wire should be bent over and tucked between the wire and terminal before it's crimped on.
For the brake pedal switch, it is probably a normally open switch that closes when the pedal is pushed. Cut the plug off and use a connector to splice the wires together.

 

[redline4]

@redline4 your son is in need

That's your progeny.
But, here goes.
2" pulley is too small. Not enough surface area. It won't be happy.
Ditch all factory wiring. Get a tethered kill switch. That connects to the ground wire on the coil.
this is the one you want.


As for the starter, you can use the factory solenoid but wire in a heavy duty push button to activate it.

If your looking to legit race one of these, I can send you some links to excellent resources.

 

[LAWN BOY]

That's your progeny.
But, here goes.
2" pulley is too small. Not enough surface area. It won't be happy.
Ditch all factory wiring. Get a tethered kill switch. That connects to the ground wire on the coil.
this is the one you want.
View attachment 437496

As for the starter, you can use the factory solenoid but wire in a heavy duty push button to activate it.

If your looking to legit race one of these, I can send you some links to excellent resources.

Okay, thanks for the info. I’ll do a 4 inch pulley on the trans instead then. Not looking to legit race it but I might one day. Giving the wiring some thought.

 

[LAWN BOY]

I just had an idea to try tomorrow, swap wiring like I wanted to, I just gotta remove the switch under the brake pedal and tape it together or connect the wires in it to bypass it. If that don’t work I might do the tether switch idea.

 

[Firewood Hoarder]

I just had an idea to try tomorrow, swap wiring like I wanted to, I just gotta remove the switch under the brake pedal and tape it together or connect the wires in it to bypass it. If that don’t work I might do the tether switch idea.

I would still advise going with a tethered kill switch. If you get thrown off, you don't want to have to chase the mower down on top of possibly being injured

 

[LAWN BOY]

I got all the wiring removed from the donor mower and will clamp the 2 safety switches shut to bypass them. Sadly my time is up at the farm so this project is to be continued. I’m not gonna do insane donuts and I’ll probably make a wheelie bar, so being thrown off is unlikely, but that probably what they all say lol.

 

[Bill G]

Kiddo,
I as well as many others here have raced many things on 3 and 4 wheels and one thing I bet all of us will agree on....

If it has tits or tires it will be fun in the beginning....in the end it will cost you money and a sheet ton of injuries.

 

[whitesnake]

Kiddo,
I as well as many others here have raced many things on 3 and 4 wheels and one thing I bet all of us will agree on....

If it has tits or tires it will be fun in the beginning....in the end it will cost you money and a sheet ton of injuries.

For sure. I’m starting to feel some aches and pains from 2 wheels.

 

[Bill G]

For sure. I’m starting to feel some aches and pains from 2 wheels.

I believe that. I did enough damage to my body and time in the hospital with 3 and 4 wheels. I the testes to try 2 wheels. I am amazed at the skill motocross guys have. Hats off to them!