Picture intensive!! If it's too many let me know and ill remove some. I am building my second go kart as my senior project, I am planning for it to look like a formula 1 car. The go kart will have a push rod suspension with dual a arms.
This is the previous go kart my friend and I built last year
Parts cut next to the old one Beginning the bracing Checking the look of where the wheels will end up Mounting point for rear wheel Starting the nose section More bracing A arms bent by my mentor Testing where to put the a arm mounts, ended up going with a single mount to make it more simple with less weight. Building the single mounts Done and in the go kart. Had to cut the bracing out because it got in the way of the a arms. Have to draw it out first! In with the old out with the new? Ended up with the second design. Before trimming the spindles After trimming and setting KPI. Droop Bump Had to redo the rear because the rim was not lower than the frame. Fixed and braced Fit looks good! Bending the side pods. Have to see what it will look like
I hope to have this done by the first race, and will update this with pictures as I get further.
Great set of pictures showing the process of the build. Looks like a very solid car. Have fun with the front suspension--it looks like a fun challenge to get working perfectly. See you at the races--hopefully by March 12th at Mt. Hood CC.
Yes, very long process trying to get the mounts and everything even. Also Mr. Mulanax told me that you might be ordering more control boxes and that you might be able to get a deal on them. I am looking for one and a better price would help since it's all pretty expensive.
With the group buy I am buying 7 at $199 each. That is with shipping to Willamette High. These are Alltrax 24-48 volt controllers. I have Mr Mulanax down as wanting one please have him let me know if he wants another one as well ASAP. I am placing my order on Wednesday this week.
Ok thank you, I just wanted to make sure they were going to be ordered. He said he emailed you.
Today I cut and tacked in the mounts for the pushrod and cut the top of the a arm mount so I could fit my steering. I didn't think about the tube for it going down the middle where the mount was, so now I have a large piece of tube to fit the bearing in and put the steering tube through that.
One reason I did it was to get a smoother ride, and so that my senior project would be approved. They wanted me to make it harder since I had already built a car last year. Also since that's the way the formula 1 cars are built now, and just to be different.
Yeah I hope it works too. I've done a lot of reading on how suspensions work and looking at pictures in different kinds of applications. The good thing is I only want 2in of travel at the most so it's a little easier. I don't plan to win any races with this car, just be able to build it and drive it (also with how heavy it will be) and have it serve as an example of the kind of work I can do.
Mr. hodgertt would you happen to have any extra tires you could sell me?
Drew out the rocker arms. Cut and drilled. Rocker arms are 2:1 which were doubled for 4:2, from what I understand I will get half an inch of suspension travel for an inch of wheel travel.
Update. The suspension does work, I set it up on one side all tacked in and was able to move around three inches at the wheel end. I did figure out that I had designed the rocker arm backwards and was able to flip it around and use it the other way. The shock is only capable of two inches before it fully compresses, and with the ratio of the rocker arm is is possible to get four.
it looks like you have put a lot of thought and planning into this. it looks amazing and i wish i had any sort of suspention on my car. where did you get the idea for this?
I got the idea from watching a formula 1 race and looking at pictures of older formula 1 cars and how they chaged up until now. The cars are interesting because they have all kinds of little things done to them to make them faster or handle better. I haven't seen another go kart that was similar to the design of a formula 1 car so I thought i would make one. . . The issue with the suspension that I hope I do not have is too much bump steer. But I will find that out when I finish up the steering arms and a few other things.
Great build thread! Please keep it going. I would love to see more of these on different design/styles of cars. Hope you are getting tech article credit for the documentation.
Maybe it is just optical, but how wide is this car going to be? It already looks to be over 4' and you will be adding another 10" with the axles attached. Please verify you do not end up over-width.
Yes, bump steer is going to be an issue, possibly a huge issue depending on the angle of the tie rods and suspension travel. Not sure yet what your exact angle will be for them, but consider trying to keep them relatively straight. If I am visualizing your points of connection correctly you will have over-steer starting into a corner (when the car goes light on the inside radius corner) and then drop into under steer as the suspension compresses. After you get it assembled it will be easy to verify this by removing the springs and measuring wheel angles throughout the range of travel. You might also consider the installation of a sway bar, without one the car may be vary tough to hold upright during cornering.
I don't get anything for putting this up as far as I know, it's just to show others who are interested.
I measured it out before and I think im still under four feet, I think it was a few inches under. If it's too wide i'll fix it later on because it has to be done in April.
I should be able to get the wheels and everything else set up next week to see how it does.
It ended up being a couple inches too wide and took two inches out of each arm to be sure (now it's 1/4in under four ft). I had to buy new shocks because the ones I had barely held the weight of the car and when I got in the frame touched the ground. I now have atv shocks that are probably too stiff, but at least they will hold me and the go kart up. Or I might be able to jump it now.
For the new shocks I drilled them out to 12mm so I didn't have to re-make my mounts and rocker arm. I also set the angles for the steering arms using the string to the middle of the back axle.
Shocks are in and hold me and the go kart up now. I had the same problem with the new four wheeler shocks, they compressed and the frame touched the ground when I got in it. We figured out the problem and it was with the rocker arms, im guessing that not only do they double travel on the shock end, they double the force on the shock. So the rocker arms were re-drilled and are about a 1:1 ratio now and hold the weight no problem.
Vice grip steering wheel Also we took it outside to check for scrub from the tires and we were not able to see any.
Well, it's pretty much done for the most part just paint and some sheet metal work that I still have to do. I did my presentation for it and exceeded my project. No pics of any of the sheet metal work just the result as I had no time. I should be able to race tomorrow so I will see if it works ok. It didn't turn out looking exactly as I wanted it, but I think it looks ok for how fast I had to get it done.
Well the first race at Mapleton went pretty good, I had problems with the throttle because the cable was slipping so I had to drive one handed. The suspension definitely works, it was nice and smooth over the whole track and you could see it working coming down the track. I actually had one side compress so much that it bent the sheet metal above the right side a-arm, so maybe 2- 2 1/2" of movement.
and one with mr. mulanax
I do need to add more camber so that my wheel won't bend outward when the suspension compresses, other than that it worked ok.
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