Offroad big block thing built from junk

[madprofessor]

Word of knowledge about those RFY gas coilovers..............The nitrogen charge is supposed to stay within a psi range of only a little more than (1) psi (a single psi) difference, don't touch that shrader valve, keep it capped. All of the adjustment is in the adjuster nut on the coilover spring.
If I'm remembering it correctly, there's 2 nuts locking together that you have to knock loose from each other to make the adjustment. Yours should have come with the wrenches (spanners?) to fit that big nut. Definitely smear some Anti-Seez on the threads before you turn the nut under any weight load, they'll start galling out.
HUGE amount of spring tension adjustment on my 17" long RFY's, see attached pic. Mine came adjusted to max softness, way too soft for my application. Adjustment at least doubled the spring rate, very surprising. NOTE: I felt the nut basically stop turning when there were still several threads left to go even tighter, and I did not force it past that point. I recommend you do the same if you adjust.

 

[Bigblockguy]

Word of knowledge about those RFY gas coilovers..............The nitrogen charge is supposed to stay within a psi range of only a little more than (1) psi (a single psi) difference, don't touch that shrader valve, keep it capped. All of the adjustment is in the adjuster nut on the coilover spring.
If I'm remembering it correctly, there's 2 nuts locking together that you have to knock loose from each other to make the adjustment. Yours should have come with the wrenches (spanners?) to fit that big nut. Definitely smear some Anti-Seez on the threads before you turn the nut under any weight load, they'll start galling out.
HUGE amount of spring tension adjustment on my 17" long RFY's, see attached pic. Mine came adjusted to max softness, way too soft for my application. Adjustment at least doubled the spring rate, very surprising. NOTE: I felt the nut basically stop turning when there were still several threads left to go even tighter, and I did not force it past that point. I recommend you do the same if you adjust.

I really had no intention of using the air system. Out of the box i held one in each hand by the top, bump stops pushed all the way up and did a pushup on them to see how far theyll compress. Half inch with most of my 220lb self on them. Good to know i can go stiffer if need be though, since im not looking for long travel. And yes, they came with the weird looking spanner.

 

[Bigblockguy]

Update time. I welded on the front section, spindle brackets, added the steering column and finished welding the shock mounts in the back. Think i got 8 degrees on the spindle brackets front to back.. And yes madprofessor, ill be doing ackerman steering.

 

[madprofessor]

I hope everyone who sees those pictures will stop to examine the structural work of the frame. That's a very excellent example of a TRUSS FRAME built from average steel tubing that's likely at least as strong as my big kart's 11 gauge 1.5" tubing, and far lighter in weight.
The over/under pair of rails is too often welded up at the ends with no bridging support. It's even more often welded with 90 degree tubes bridging between the rails to make a LADDER FRAME.
Your frame is twice as strong as that because of the OPPOSING DIAGONAL bridging that constitutes a truss frame. You could walk through any big warehouse or ball park or other such open structure, look up, and see the exact same kind of trusses holding up the roof.

 

[Bigblockguy]

I hope everyone who sees those pictures will stop to examine the structural work of the frame. That's a very excellent example of a TRUSS FRAME built from average steel tubing that's likely at least as strong as my big kart's 11 gauge 1.5" tubing, and far lighter in weight.
The over/under pair of rails is too often welded up at the ends with no bridging support. It's even more often welded with 90 degree tubes bridging between the rails to make a LADDER FRAME.
Your frame is twice as strong as that because of the OPPOSING DIAGONAL bridging that constitutes a truss frame. You could walk through any big warehouse or ball park or other such open structure, look up, and see the exact same kind of trusses holding up the roof.

Thank you. There was a time, half a lifetime ago, where i studied engineering. Though the only thing i mastered was chasing skirt and building a popsicle stick bridge. I havent weighed it, but as it sits today with the rear axle, steering setup (which is all 1" solid round that i had laying around) and the front hub assemblies, id say its around 160 lbs.
Now the bad news. Its wracked somewhere. When i put it on the ground, one wheel hub is on the ground, the others 3/8 of an inch in the air. Guess ill have to shim the low side up a bit. No biggie bc i gotta add washers to offset the springs compressing under weight.

My question professor, is is there a formula to figure out how long to make my pitman arm and the tie rod arms on the spindles? I cut a piece 3 1/2 for the pitman, bit to achieve proper ackerman im gonna have to go up, out, back in and over to have 45degrees each way on the spindles bc, quite frankly, i shouldve made the spindles longer and thicker. Just plain flat stock hits the spindle bracket.
Sorry for the long response.

 

[madprofessor]

Sounds like the frame wasn't clamped down solid during welding, warped upward as you went. Betting you'll fix it right and proper though, because you understand the meaning of the words "rack", "racking", "racked", and "out of rack". You only spell it wrong.
Here's a link to the spindle sets I ordered without thinking. Problem: They're 90 degree spindle arms, no ackermann angle at all.
AZ2231 - 4-1/2" long Spindle & Bracket Set - Side 1, 3/4" axle | Go Kart & Mini Bike Parts | MFG Supply
Point being, even with an 8' wheelbase, I have perfect zero offset ackermann angle. How: Cheap 120vac inverter stick welder. Tripled up the strength of the spindles with more steel while adding flat and angle iron as offsets and angles to them, drilled new holes for tierods connections.
You can add on iron to your whoop-dee-doo requirements as needed, go around any obstacle or cut it away, get any ackermann you want. Treat it as a Build-A-Bear assembly job, as we say, "bend that metal to do your will".
(BTW: My pitman and spindle arm formulas is to make it longer than I could possibly use, and drill a series of holes in it for tryouts.)

 

[Bigblockguy]

Sounds like the frame wasn't clamped down solid during welding, warped upward as you went. Betting you'll fix it right and proper though, because you understand the meaning of the words "rack", "racking", "racked", and "out of rack". You only spell it wrong.
Here's a link to the spindle sets I ordered without thinking. Problem: They're 90 degree spindle arms, no ackermann angle at all.
AZ2231 - 4-1/2" long Spindle & Bracket Set - Side 1, 3/4" axle | Go Kart & Mini Bike Parts | MFG Supply
Point being, even with an 8' wheelbase, I have perfect zero offset ackermann angle. How: Cheap 120vac inverter stick welder. Tripled up the strength of the spindles with more steel while adding flat and angle iron as offsets and angles to them, drilled new holes for tierods connections.
You can add on iron to your whoop-dee-doo requirements as needed, go around any obstacle or cut it away, get any ackermann you want. Treat it as a Build-A-Bear assembly job, as we say, "bend that metal to do your will".
(BTW: My pitman and spindle arm formulas is to make it longer than I could possibly use, and drill a series of holes in it for tryouts.)

I just remembered. I made those spindle brackets by hand, with torch and hammer. One is a little bit longer than the other. A few strategically placed washers should fix that. As i said, i have to add some to preload the springs anyway.
I used 6" grade 8 bolts for the axles, so i got about 4 1/2 of smooth usable shank. All the wheels i see online in 8x8 seem to be offset, so im gonna hold off welding the stops til i buy rims, but my earlier question about keeping the centers of the front and back wheels in line seems to have worked itself out. I got 41" hub to hub in the rear, or 20.5 each way from center. From the front crossmember to the outside of the wheel hub is 17. So pretty much any offset rim used in a deep dish fashion should work there.
Good advice on the pitman and spindle arms. Ill try it out.

 

[Bigblockguy]

If i leave the motor centered, i know id be fine using a centrifugal clutch, but i planned on using a 40 series tc. Am i gonna end up w clearance issues with the tc cover?

 

[madprofessor]

clearance issues with the tc cover?

If that means you're getting a 40 series mounted on a backplate that you want to put the plastic cover shroud on, you can do it. Remember that there's bunches of holes in those backplates for changing the angle of the mounting, and it doesn't have to just protrude toward the rear. You can mount them completely forward, straight down, or up if the engine clearance is there, etc. Attaching pics of some 30 series mounted straight down, and mounted toward the back with a downward angle to get clearance.

 

[Bigblockguy]

If that means you're getting a 40 series mounted on a backplate that you want to put the plastic cover shroud on, you can do it. Remember that there's bunches of holes in those backplates for changing the angle of the mounting, and it doesn't have to just protrude toward the rear. You can mount them completely forward, straight down, or up if the engine clearance is there, etc. Attaching pics of some 30 series mounted straight down, and mounted toward the back with a downward angle to get clearance.

So the cover doesnt really stick out much past the end of the shafts? I plan on running it toward the back and downward, but i shouldve specified that i meant side to side. I have plenty of clearance front to back if i need to move the motor forward, and if necessary i can run a jackshaft setup in front of the motor and put my 60t on the pull cord side. Still not sure what im doing for brakes, so i want as much room as i can to mount them.

 

[madprofessor]

No measurements, but maybe the pictures here will give an idea how big the shroud is....................
40 Series 1" Driver 5/8" Driven Torque Converter Clutch Pulley Kit for Go Kart | eBay

 

[Bigblockguy]

Update time. I finished the front half of the frame, added pedals and cable clamps blasted, primed and painted it. On the rear i added an extra bearing set and outriggers so it wont bend the axle coming down from jumps. Fabbing up skid plates. Not sure what im gonna do for brakes. Id planned on using the manual caliper from gopowersports but it got **** reviews. Prob rig up a hydraulic setup from a dirt bike or something.

 

[Budget GoKart]

epiiic! i plan to use only lawn mower parts to build a go kart lol

 

[Bigblockguy]

epiiic! i plan to use only lawn mower parts to build a go kart lol

As the title suggests, i had originally planned on building the kart from scrap at my job. Then i remembered that i can afford decent metal and have access to professional fab equipment.

 

[Bigblockguy]

This will be my last update til after new yrs bc im saving for brakes, wheels and a torque converter, but its home and largely assembled

 

[Bigblockguy]

This will be my last update til after new yrs bc im saving for brakes, wheels and a torque converter, but its home and largely assembled

 

[FlyFrog]

My 64' wants to talk

View attachment 128942

Sweet build!

ya but the driver side will stick out or be even with the rear wheels, thats how almost every car on the road is(unless its a dually like others said it might be)

 

[Denny]

Happy New Year!

 

[Bigblockguy]

Aright time for an update. My boss sold me the rear wheels cheap and I treated myself to a 40 series comet tc. The engine is now mounted and quite frankly, it rips. This is gonna be one badass buggy.

 

[Bigblockguy]

Figured out that the same 22x11-8s that I put on the rear also work on the front. Fronts were sitting TOO cocked, so I adjusted the spindle angles and added 3/8 gussets to the spindle arms. Won't be long until it's time to throw a bottle of yuengling at it and give it a name.