JCRacing's Racin Trapter

Hey guys, here is my racing mower and all of the parts I have at my house for the build-off.


Here are some of the parts:

1" Deluxe Flex proof solid axle and the whole chassis has 1" square tubing running through it.

14.5 Briggs I/C quiet ohv, it has the EC Carbs velocity stack and air filter

The front axle is made out of 1"/3" rectangle tube


This is the rear sprocket, it has a racheting hub system that I made and designed to keep the pressure off of the tranny when I shift. On that note I am also using these parts:

Peerless 700 with four shift keys, I made it a 5 speed, and it has roller bearings on the output shaft
Rear tires are mowku turfs that are 16x6.50-8 on 8x7 golf cart wheels
homemade from spindles using the spindle mounting brackets from BMI Karts
Homemade automotive/motorcycle stye clutch

I am hoping to have this thing move at 45-50mph and do donuts all day.
Thanks for reading and happy building!

DOH! Honey I ate the photo's!

Lawren Wimberly wrote:

DOH! Honey I ate the photo's!

Fixed!

Fantastic. Welcome to the forum and to the Build-Off, good luck. I am intrigued by your ratchet mechanism. Interesting indeed, but eliminates all engine braking, no?

It does and reverse will no longer work. These are some downsides of it, but I did not want to run two clutches. If it is too loud and does not work very well I will make a second clutch for the output on the tranny. My hope is that if I remove all of the load on the peerless when I shift I won't ruin it and it will be easy to shift. Too bad they don't have syncros!

Ratcheting sprocket is cool indeed! I don't think you'll loose reverse anyways, most people with speed mowers ditch reverse chains.

Double post? (Delete this)

Yeah I was already planning on taking it out. The reason most people take the chains out is for high hp and high speeds, but what it you kept the input on the tranny at stock rpms, but instead if putting a small sprocket on, put a large one. So you would speed it up after the tranny. The only thing I would think could hurt it is high hp and the more torque on te output shaft. Do you think that would be an issue? This would not work for transaxles.

The reason that not only to most racers take out the reverse chain, and indeed most sanctioning bodies DEMAND you take the chain out is this-

The reverse chain in the 700 is always moving. At racing speeds, it's always moving fast. There is very little clearance between the larger reverse sprocket and the case. If the chain should let go, there is a very high likelihood it will try to wrap up, bind, and literally blow the case apart from the inside out. Reducing your input speed reduces the risk, as does installing a chain, as does installing a higher quality 420 chain, as does oil-filling the case. But the risk cannot be entirely eliminated, as long as there is a chain in the case.

Alright, so reverse chain just does not seem like a good idea at all. I have a question about brakes, I would like to use hydraulic brakes, but I do not have the budget for the standard $250 racing Kart brakes. Has anyone ever tried to use like 125cc pit bike brakes? I have had my eyes on these http://www.ebay.com/itm/Rear-Hydraulic-Brake-Assembly-Caliper-Cylinder-Dirt-Pit-Bike-ATV-70c-110cc-125cc-/321220659225?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item4aca3e4819 and they seem like a pretty sweet deal. They are dual piston so I was thinking they could probably have some good stopping power, maybe even run two of them.

JamisonCampbellRacing wrote:

Alright, so reverse chain just does not seem like a good idea at all. I have a question about brakes, I would like to use hydraulic brakes, but I do not have the budget for the standard $250 racing Kart brakes. Has anyone ever tried to use like 125cc pit bike brakes? I have had my eyes on these http://www.ebay.com/itm/Rear-Hydraulic-Brake-Assembly-Caliper-Cylinder-Dirt-Pit-Bike-ATV-70c-110cc-125cc-/321220659225?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item4aca3e4819 and they seem like a pretty sweet deal. They are dual piston so I was thinking they could probably have some good stopping power, maybe even run two of them.

I got these for the same reason you mention, and I liked the look on them, heavy duty.

http://www.ebay.com/itm/181122819061?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

Have you used them yet? I'm curious because those only have one piston and I am wondering I'd you think that is enough.

JamisonCampbellRacing wrote:

Have you used them yet? I'm curious because those only have one piston and I am wondering I'd you think that is enough.

No but they have more stopping power than those you linked too, cause I have those too. and they are flimsier built.

good luck

I really like the ratcheting hub idea, I think its very interesting. How are you going connect the tranny to the rear axil? I'm guessing your gonna turn the tranny into more of a gear box type of deal connecting it to the axil? Pics would be awesome. Very nice work!   

Thank you. It will be set up normally I you were running a 700. I built the ratcheting hub on a sprocket and that will be on the rear axle. From that sprocket a chain will go up to the transmission. Does that clear it up? And sorry I don't have any pics, but I havn't mounted it up yet.

So I finished the spindles with bushings and spacers. They are made out of grade 8 3/4 bolts (should be strong enough lol) and 1/4 plate welded together at about a 2 degree positive camber. In this picture the whole mower is upside down, so the head will actually be on the top.

Parts update: I am using a mechanical snowmobile brake and instead of using an automotive clutch i will just be making the standard double pulley clutch. Also I got a new push button starter, a bike computer for a speedometer, and flanged 3/4"id 1 3/8"od high speed bearings for the front wheels.

I have also ordered a whole bunch of parts from surplus center including bearings, pulleys, and sprockets.

Those are sweet spindles! Where did you get the brass bushings?

I made them! For half of my day at school I go to a vocational program where I am learning machining.

Can you go into some detail on the bike computer thingie?

Possibly a link?
Also how would you hook it up?

JamisonCampbellRacing wrote:

I made them! For half of my day at school I go to a vocational program where I am learning machining.

Sweet! I go to a vocational school as well in ny for diesel mehcanics. Machining helped my partner out with getting a broken bolt out of a clutch basket. Complicated class lol

Can I suggest nylock or castle nuts on the spindles? I'd hate to have 'em come loose

LAWN MOWER MUDDER wrote:

Can you go into some detail on the bike computer thingie?  

Possibly a link?
Also how would you hook it up?

I havn't seen any articles or threads about it, but my idea was to put the magnet on the wheel or brake rotor, and then put the pick-up on frame some where. The new computers allow you to input your own size wheel, so I will just put my tire size in. They work by measuring the number of wheel rotations (rpm) and then multiplying that by the wheel size to get the speed. So as long as the magnet doesn't come flying off, it should work, and if not it was an $8 mistake.

Lawren Wimberly wrote:

Can I suggest nylock or castle nuts on the spindles? I'd hate to have 'em come loose

I will do that, it just didn't want to deal with the nylocks in mock up.

So, this past week or so I drilled the holes in my transmission plate and then tacked it into the frame. I don't have a picture of the bolt holes or the aluminum support bushing that I made.
Here it is mounted in the frame.

I also started to make the clutch. It will be a dual pulley clutch. I made the main part out of 3/8" steel plate and the bolts for the pulleys are both grade 8. the pivot bolt will be a grade 5 3/4" bolt that will ride with brass bushings in a large aluminum mounting hub. I really did not have any flex in the clutch lol. Here are the pictures

I have some more parts coming, as well as many new updates because the build is starting to move a lot faster.