Front End Problems

[jasonH]

I am on the home stretch of my first build. I got to take the kart out for it's first voyage yesterday. I noticed the steering was very stiff and it didn't turn well at all. The pictures aren't current but as close to current as I have. I have the tie rods running in between the a arms. It does have new tires. The other problem I encountered was the top of the driver side tire tipped in significantly. The top of that A-Arm dropped to rest on the shock and would not come out of it. If you guys need the most current pictures i could head up and snap a few. hopefully these are good.

 

[OzFab]

Wow, where do I start...

Sorry but, I see a multitude of problems, the main one being the connection between the A arms & the hub; to work efficiently (as in, to allow for steering) the bolt holding the two plates on the hub needs to be a bit loose, if it's tight, then you can't steer; the problem there is, if it's loose enough to allow for steering, the plates have a chance to move around, causing the whole front end to simply not work...

Get yourself some rose/heim joints, attach them to the ends of the A arms & get rid of the solid plates; that may also fix problem #2:

The A arms are not parallel, meaning the camber angle will vary through the vertical travel of the wheel...

Apart from that, I can't comment on the steering because I don't see any...

 

[rocketkart]

your shock tower looks extremely dangerous. hope you have plan on reinforcing them.

 

[jasonH]

Fabroman- thanks for the advice. I suspected that was my problem area but being my first build I am mostly blind. I did a quick Google search for them. Thanks for taking it mostly easy on me.

 

[jasonH]

your shock tower looks extremely dangerous. hope you have plan on reinforcing them.

Yeah I do. I still need to go through and reinforce the whole kart. After I mocked the basic Frame up I decided I better mock up all other components of the kart before I got too crazy. Being my first one it's been mostly design as I go.
.

 

[OzFab]

Thanks for taking it mostly easy on me.

Hey, we were all beginners at one point It all comes down to how you accept "constructive criticism"

 

[landuse]

Hey, we were all beginners at one point It all comes down to how you accept "constructive criticism"

Well said!!

 

[jasonH]

Hey, we were all beginners at one point It all comes down to how you accept "constructive criticism"

i can both handle and welcome constructive criticism . It's the A-hole criticism I can do without. I have to say that this forum has been very helpful and lacks the A-hole criticism. Kudos to the community.

 

[jasonH]

Wow, where do I start...

Sorry but, I see a multitude of problems, the main one being the connection between the A arms & the hub; to work efficiently (as in, to allow for steering) the bolt holding the two plates on the hub needs to be a bit loose, if it's tight, then you can't steer; the problem there is, if it's loose enough to allow for steering, the plates have a chance to move around, causing the whole front end to simply not work...

Get yourself some rose/heim joints, attach them to the ends of the A arms & get rid of the solid plates; that may also fix problem #2:

The A arms are not parallel, meaning the camber angle will vary through the vertical travel of the wheel...

Apart from that, I can't comment on the steering because I don't see any...

Ok so... After looking around for the heim joints I think I may have a issue. My hubs have a 3/4" bolt going through holding the A Arms. I can't seem to find any heim joints that big. Are they able to be found? Or should I redo the hubs to fit a more standard size heim joint? The kart will be driven by kids on a 400 acre property with lots of rugged terrain so I want something that can take the abuse. Thanks in advance

 

[Brian Hadden]

tractor supply has some that are 3/4 look at three point hitch parts under agg

 

[jasonH]

tractor supply has some that are 3/4 look at three point hitch parts under agg

Thanks Brian

 

[OzFab]

You could also try using a 1/8" bush/shim in the hubs & drop down to 1/2"...

 

[wagx2]

shocks are upside down, and looking at the picture is that a hinge point at end of a-arms with the plate going out to the king pins if it is. it should not be there. steering is stiff because when you adjust the steering the rods are in one position and as your driving the pivot point moves up and down so it will act like your trying to turn while to donkeys are playing tug-o-war with tie rods cause one minute forces are applied in on both rods and the next there pulling that pivot should not be there if you have this on the ground and take tie rods loose it will fold up and be slammed on the ground like it had hydraulics, so your tie rods are taking all the weight of front end not the shock. if the a arms are spaced exactly the same on both sides take the pivot off or weld it in place. yes brace the shock towers and tie them together at those top points, and gussets but your king pin needs to be where hinge is. have someone take a video of you driving toward them, bet the wheel look like a barefooted baby running across the rocks.

 

[wagx2]

Sorry about my funny explanation of what's happening with the steering, but in laymen terms the way it is set up you have a arms with mini arms on the end of them, and one set has a shock and mini set has a tie rod, instead of another shock. repeat sorry not criticizing you and you did post you were open to the good and bad.

 

[wagx2]

best fix would be to remove the top a arm a a-arm system will not work without ball joints. since that hinge is there let it tilt in a little then weld it in place and add tube from it down to bottom arm then it will be wishbone front suspension and you want have to fab up much, ex:

 

[wagx2]

also the top shock mount looks like its 3'' in front of the bottom mount and you have the mount bar for the top mount angled back, move the top mount back so that it is directly in line with bottom mount angle shock more so it will absorb more of the bumps in the terrain your running on. then the top mount can be 1 piece and join both sides, gussets off front and back and one just before top mount, and problem of arm sitting on the spring check tie rod it may have bent due to the hinge point.

 

[jasonH]

You could also try using a 1/8" bush/shim in the hubs & drop down to 1/2"...

The hub has a bushing in it now dropping it from 1" to 3/4". The hubs/tires/rims are all from a riding lawnmower (reinforced)

 

[jasonH]

Sorry about my funny explanation of what's happening with the steering, but in laymen terms the way it is set up you have a arms with mini arms on the end of them, and one set has a shock and mini set has a tie rod, instead of another shock. repeat sorry not criticizing you and you did post you were open to the good and bad.

Thanks for the explanation. no hard feelings here. Big shoulders

 

[jasonH]

also the top shock mount looks like its 3'' in front of the bottom mount and you have the mount bar for the top mount angled back, move the top mount back so that it is directly in line with bottom mount angle shock more so it will absorb more of the bumps in the terrain your running on. then the top mount can be 1 piece and join both sides, gussets off front and back and one just before top mount, and problem of arm sitting on the spring check tie rod it may have bent due to the hinge point.

View attachment 57756

Not quite 3", but yes it is forward. The Karts frame is angled and instead of building a square box on the front of the kart for the front suspension I opted to just build the A arms on the angle of the frame. My thought process was I can keep the Kart shorter and lighter if I did this but after reading your post I probably shouldn't have. I have plans to reinforce the shock mounts as well as the rest of the Kart. Just haven't made it to that step yet.

 

[firemanjim]

I gotta agree with wagx2 on just about all of it.
Shock angle is wrong, easy fix. The A arms... Hmmmm dith the top one , reinforce bottom one like wags pic. The shock would be the upper mount/stabilization point.
The plates at the end of the arms GOT to GO! Main problem..... IMO It is the cause of the top flop and resting on shock.
Put heims on the ends, like a sandrail.... I'll post some pics in a bit, for inspiration....
Great attempt at your first kart. Keep your chin up, you did nothing wrong. We all started some where....