The Trainwreck

[Tommy Boy]

That's what I'm gonna call this piece. Because it's been nothing but a trainwreck so far. Been meaning to post a build log since I registered, but never got around to it. Anyway, here it is and where I am so far.

Right out of the gate I'm kicking myself in the pants for not throwing down a buggy frame. When I started the project, it was originally street and lawn but eventually morphed off the charts into something bigger. But I'm still stuck with the frame (without cutting it down and reworking the design), which is 6' total length, 4' front 2' rear with a swingarm, 3' wide.

http://members.cox.net/firemanat25s/cartbuild2.jpg
http://members.cox.net/firemanat25s/cartbuild4.jpg

The plan is cheap, cheap, cheap. I need a kart like I need an extra butthole in my forehead. But after scrounging every salvage in town for a motorcycle donor and reviewing the cost of parting one out via Harbor Freight and other outfits, the cheapest solution I found was, you guessed it, Craigslist and a used 12.5hp Murray rider. And here lies the conundrum.

Option #1: Cannibalize the rider for the kart. Use a centrifugal clutch on the motor shaft and redirect the drive via fixed idler to the live axle.

Option #2: Cannibalize the rider for the kart. But in lieu of a centrifugal clutch, build a manual clutch similar to the onboard clutch of the rider, cable actuated and tightened to the drive belt with heavy springs, as indicated in the following.

http://members.cox.net/firemanat25s/beltdrivediagram.jpg

Option #3: Screw the kart. Rework the transaxle, change up some pulley ratios, and get this sucker on the track.

The longer and further I get into this, the better #3 is sounding. I still haven't put hands on shocks for the suspension, have yet to build the steering linkage, and will probably either A) scrap the existing frame for a more buggy-styled design or B) cut it down and rebuild it. In other words, I'm not so far down the path that I can't abandon ship. I also have yet to hear or see a vertical shaft set-up that's efficient and reliable, having heard all the horror stories about burning through belts.

So the Trainwreck is at a crossroads. What do YOU guys think?

[Kaptain Krunch]

Make yourself a beater mower outa the murray while you save up and build a nice kart.

[Kevin Noah]

Put on a 2" pulley on the crank, then put a 3" pulley on the trans. and hold on.:idea2: :idea2:

[Tommy Boy]

Almost forgot. The Trainwreck's organ donor.

http://members.cox.net/firemanat25s/cartbuild1.jpg

Help me start a punchlist, gang. Here's what I know I'll have to do so far. If you think of something else, add it to the list for me.

* Lock the front axle, possibly notch and lower
* Rework the transaxle (It's a peerless, unsure of the model)
* Shim/tighten the steering linkage
* Check into brake options (not sure how just yet as I'm not dumping a fistload of cash on wheels and hubs for this piece of you-know-what, ideas appreciated)
* Paint prep/breakdown
* Throttle pedal fab/relocate
* Lights and sirens

Being a fireman by trade, this one is a must.

Anything I'm missing?

[bigfootrules31]

so are you making a gokart or moding the mower, i think the mower would be much better.
everyone else managed to find a mower but i cant seem to :mad2: i just started my 2 weeks of school holidays and me and my friend were planning on makin a racing lawn mower. atm im annoying the :censored: out of a guy to let me buy his lawnmower that hasnt been used in ages.

[Raywelder]

Check out Heymow.com
Lots of pics, will give you an idea about how to lower, and modify.
But dont post there, they will ban you.
No lie.

Then you could always build up the cart frame later!

[Kaptain Krunch]

-Definitely tighten steering linkage

-i would find some better tie rod ends (i've broken stock ones just mowing)

-Change up pulleys dont go any smaller than 4" pulleys, smaller is less surface area, more slippage.

-If your keeping stock brakes get some new pads/cut some out of an old set of car brake pads.

-lower seat

-If you want to lower the front end, just turn the axle upside down (not the spindles just the axle)

-If you want you can find a rear kart axle and a peerless 700 series and run that, it would be much easier to set up brakes and the transaxle is stronger

You should make a hood scoop too, then we can see who's comes out better (yours probably will).

Like ray said, go to heymow and look through the builds but dont post anything about you making a mower that isnt going to run in a sanctioned event, they will flip **** and might ban you.

[Raywelder]

Like ray said, go to heymow and look through the builds but dont post anything about you making a mower that isnt going to run in a sanctioned event, they will flip **** and WILL ban you.
Fixed :arf:
They will ban you just for being under 18, they flat out said they dont want kids in their sport, I was real interested in the sport, but that website has really turned me away from it.

However, the site has TONS of info and pics.

Idk I would flip the front axle, Doesnt seem like that work very well to me.

You can tighten your steering linkage, however you best bet is to replace all the steering with a go cart like set up, ( check heymow, tons of setups for that)

[Kaptain Krunch]

Fixed :arf:
They will ban you just for being under 18, they flat out said they dont want kids in their sport, I was real interested in the sport, but that website has really turned me away from it.

However, the site has TONS of info and pics.

Idk I would flip the front axle, Doesnt seem like that work very well to me.

You can tighten your steering linkage, however you best bet is to replace all the steering with a go cart like set up, ( check heymow, tons of setups for that)

I guess i never said i was under 18, but i did say a$$ once and they flipped out, i mean thats barely a bad word.

For flipping the axle, i mean just the axle, not the spindles or anything else, since the axle is bowed down in stock form. It may throw off the steering geometry a bit, but cant be much worse than stock.

Heres the front end i made, its not precision but its better than stock ( i think the spindle brackets are a bit too thin, but maybe not).

http://i523.photobucket.com/albums/w355/houdinky/06-20-09_1544.jpg

[Tommy Boy]

Okay, on the subject of spindles.

We already went through the madness that was drilling out that cotter pin, so I know I have at least heat treated steel working on the round spindle stock. So instead of cutting off the spindles from the A frames I built for the cart, I had an idea. Why not tap threads on the existing spindle stock? It's as thick as anything I would've personally made (3/4 round), the spindle mount itself is better engineered and thicker than stock I would've used (going to add a grease zert for a direct lube option), so why not roll with it? I had to cut the threads and cut down a castle nut to fit on the spindle, but with a little grease, we now have a fixed retaining nut backed by a washer and held by a cotter pin.

http://members.cox.net/firemanat25s/castlespindle.jpg

Amidst all that, I tried to pull the main pulley from my transaxle, an MST-205 Peerless. Good news is according to the Tecumseh specs, this thing isn't a grease packed transaxle, but instead comes stock with a 80w90 gear oil which ought to keep the clean up simple. If only the pulley was as simple.

http://members.cox.net/firemanat25s/pulley.jpg

Tried the gear puller/WD-40 thing today. I'll be trying some heat tomorrow. Pray that I don't have to cut this **** thing off.

Update tomorrow!

[Tommy Boy]

Pulley is off, new pulley is on, belt in place and road/track tested today to check for drivetrain bugs, belt slippage, et cetera. Good thing I did, too. I have a front end problem.

The spindles? Worked like an absolute champ. Tight, no cotter pin wear (thanks to the castle nut), and as far as I can tell, the set up as is should work, short of welding up the front crossmember. The problem is these stupid front wheels. Pressed plastic wear bushings, and thanks to an error in assembly (missed the outside washer on the right front spindle), I managed to wear off the flange and push it into the wheel assembly. I was easily able to punch out the bushing, so we're good there. The only problem is the set up itself.

Surely there's a place to get ahold of shielded and flanged bearings to press into this stock wheel, right? Something I can tap a cert in the backside of the center of the wheel to lubricate, but still shielded to the flange side? I looked all over McMaster-Carr and could find a 1 3/8" OD bearing, but no 1 3/8" OD bearing with a 3/4" ID.

Ideas?

[Carlman]

I replaced the platic bushes on some bolens stock wheels with bearings from a MTD if thats any help

[Tommy Boy]

I hit the phone book.

Come to find out the Bearing Capital of the World is right here in the friendly confines of Tulsa. Allied Bearing. They had some 1 3/8" x 3/4" flange bearings in a box under the counter. The guy working there just chuckled as he set my 4 bearings out, telling me that lots of folks buy these. So much so that they keep them handy up front. Got 'em installed today. Very slick and MUCH more stable than those stupid wear bushings.

http://members.cox.net/firemanat25s/wheelbearing.JPG

Also got the motor pulley swap done. Instead of banging the countryside looking for a 1" bore pulley, I went redneck and flipped the twin pulley, tapping a couple of holes in the shaft for 1/4" bolts to ride in the keyway. This gives me 4" at the transaxle, and approx. 6" (don't remember the measurement offhand) at the engine. I kept the 3" original drive pulley in the stack because eventually, she's getting an alternator and lighting set-up.

http://members.cox.net/firemanat25s/drivepulley.JPG

Now, here's the conundrum. If I understand it correctly, I'm .66:1 with 6" drive, 4" transaxle pulleys, effectively throwing over 3000 RPM on my MST-205. It's still too slow. Granted, she's faster than she was with the 3" drive pulley, but not what I'm looking for. However, I don't want to continue slapping bigger and bigger pulleys on the engine because I'm already overspeeding the transaxle as it is. I know the answer is live axle and increasing the transaxle output there, but if I go moving my transaxle around to accomodate, I'll have to redesign my shift linkage AND clutch idler position. So at this point, I'm reduced to thinking I'll need to actually extend the frame itself, mount pillow blocks, and drive the live axle via sprocket assembly. But with this, I have the long axles of the transaxle in the way of the wheels themselves unless I cut them down, a step I'm not willing to take.

Ideas on this?

[Kaptain Krunch]

peerless 700 series.

How much were those bearings?

[Tommy Boy]

Seven bucks and change a piece.

They're not sealed, but they're at least shielded. Better than a kick in the junk. And with that, I can eventually tap a zerk in the wheel and just load it with grease or give 'em a shot of graphite every so often.

And another transaxle isn't an option. Should've indicated that in the previous post. This scoot has already blasted any expectations of keeping the cost down, so anything further has to be free, cheap, salvage, or engineered/fabricated from base stock.

Hate to pigeonhole the options, but that's what I got. Hence the dilemma.

[Kaptain Krunch]

Have you done anything to that transaxle? you could sell it on heymow and then get yourself a 700 in a junk yard. Is it really that geared down? what speeds are you getting to right now?

[Tommy Boy]

Haven't paced it or measured it. I'm assuming 20-25 MPH, just on feel.

According to the numbers I've researched, it's .6:1 in 5th, with an assumed 3000 RPM (3600 rated) at full throttle due to no engine mods. .66:1 on the pulleys, 56" tire circumference @ 18", so...

If my calcs are right, I'm going over 300 miles per hour. Now I understand why you need to brace the front axle and add brakes. I plan on getting a bigger pulley so I can hit escape velocity.

Help me out, guys. My math ain't right. 6" drive, 4" transaxle, a 6/10:1 ratio in the transaxle @ 5th gear and a 54" tire cirumference at 18" diameter. I don't know how much I'm losing in belt slip, but it's definitely biting strong. Strong enough to pull a wheelie and not a single squeal, so I'm not losing much.

[Tommy Boy]

This thread hereby lives.

More pictures coming in time, but an update. Let's go through the laundry list.

Front end, done. Raised and welded the existing front axle, told you guys about the spindles in a previous post, et cetera. I can't get the front end lower without getting too close to the secondary pulley from the original pulley stack. It sits good enough for my liking and has a nice, low stance. Needs more weight in the front as she'll push through turns if you stay wrapped out.

Steering. Punched out the existing ball joint bolts on the spindle arms and pitched the crappy steering linkage arms. I kept the existing spline gear set up though as there's zero slip, it's functional, and I didn't want to figure out how to ghetto up a bellcrank around the pulleys. Heim ends to new 1/2" hardware, creating an entirely new linkage. Zero slop, stiff but not tight, and ten times more sturdy than the old set up ever thought about. To accompany this, built up a box frame in the console from 1" 18 gauge square tube.

Throttle linkage. Built a pedal on the right floorpan, wired it up. I got some cable slip issues here, but not from placement, from the way I've connected the cable to the pedal. Essentially sandwiched two fender washers, one with 3 holes drilled to accomodate a weave of the throttle cable. Bolted through the bottom of the pedal. Throttle return comes from the idler spring off the deck, connected from the pedal to the frame.

I tried my best to make some changes in the drive pulley, but it was more heartache than anything. When I did my RPM calcs, I was using measurements off the outside diameter of the flutes of the drive sheave, NOT the valley of the sheave. Which everyone who's ever looked at a mower's drive pulley knows is a pitched pulley with a deep valley to allow belt slip without throwing the belt. So that 8" industrial pulley managed to waste my money because I couldn't keep belts on no matter how many lasers and straight edges I used for alignment, no matter how many belt guides and blocks I set. When I kept the belt tight, that 2:1 ratio was sick nasty fast, but I don't have enough horsepower to push it and get all my RPM. Which leads to a driveline change...

Went back to stock, removed the chintzy through bolts and notched the pulley shaft to accept some keystock. Couple of pipe clamps and bingo. No pulley slip, no vibration rattling the bolts from the keyway, no welds to fail under torque. What's that mean for the ol' Trainwreck?

She's a paintjob away from almost done. And she still ain't got brakes. Screw Heymow.