And there seams to enough space besides the seat. The angle might need to be lower than 45 but hard to say with out doing the math or just experimenting.
It might really solve a lot of issues if you re-mount the top of the rear shocks more toward the front of the kart, at least at a 45 degree angle, it will soften the suspension and also help prevent the rear from pivoting like that.
Move the top mount further forward and lower until you get it softer. But looks like you want to keep it there because it’s the strong part of the frame
The bar you installed is a track bar. Keeps the axle from making lateral movements. Also if you can, I suggest lowering the angle of the track bar a bit, otherwise when the suspension compresses it will push your axle to right causing a kind of rear bumpsteer. If you can get the bar closer to horizontal, it will minimize this upon normal suspension travel, where as right now, it's bound to move the axle at least an inch or two depending on how much the suspension compresses. I hope this helps you out, I love your videos man, the fully suspensioned go cart is my favorite build yet! Keep it up!
Since you took the 420cc off and replaced it with a 670cc can you just ship me the 420? Well actually I’ll take the 670 too. I’ll actually just take the whole go kart thanks
You do realise that a panhard bar does that anyway, right? However This will be a bit more extreme due to the angle compared to a regular panhard setup. Best setup for a solid rear axle is a watts link.
That's what I was thinking. I'm thinking should've squatted the suspension and then made the bar. But doing that may make it pull the rear end to the left at ride height.
Maybe one of those shocks in the middle. Would make the rear twist more too, be good for climbing obstacles. Panhard bar should be level so when suspension flexes it stays mostly in the center of the buggie due to it's ark of travel. .
To soften the suspension, you might be able to grind off the lower plate that the spring rests on and re-weld it at a slightly lower spot. Thus decompressing the spring slightly.
The engine sitting in the suspension portion is considered unsprung weight. Simply, it's not putting weight on the springs, rather its putting weight underneath them. Best bet is to get springs with a lower force constant. Also, as the suspension travels upwards, that connecting link will force it to move to the right. Not sure of a fix for that. Cheers.
@@jm036 This is by far the simplest and easiest way, and works well enough to provide adequate suspension. Many manufacturer-produced buggies/off road karts do it this way.
You should make an offroader side x side out of a 4 wheeler just making it longer and wider by extending the drive arms and extend the drive shaft that goes to the front wheels. You could also extend the diff by making the axle inside it longer on the lathe and just get a bit of pipe and bearings that fit over it for strength
The stock 670 only does around 2000 rpms. Add 18lb valve springs and remove the governor cam from inside the crank case and limit the rpms to 3600 rpms at the throttle. This is a safe way to get the most out of it without spending a ton. Also, I personally would like to see someone make the motor quiet instead of bone crushing exhaust. Waking up the neighborhood isn't what it cracked up to be.
Hi Cris, is it possible to make a small segment on how you make such perfect bends with that style bender in a future vid? I have the same model an the tubing keeps kinking an really frustrating. Awesome work an take care especially with Florence.
Isn't it possible to implement a mountain bike gear changing system to a gokart to gain speed? Wouldn't you think once the go kart is in motion changing gears would be easier on the engine in higher gear?
Hey man! I can’t find a dang tube bender that under $500 I went to harbor freight and got their compact bender and all it does is kink my tubing what kind of bender do you have and did you have to do any modifications? Let me know please I am in need of one like right now!! Thanks a ton man!
Should weld a bar in behind the seat and angle the tops of the shocks in and also the flatter the Panhard bar the less the rear will move side to side during the suspension cycle.
made the comment at RBG, to stop that rear steer, set up a torsion bar! even though it's not a diff, it'll stop rear steer AND help keep it level turning fast etc. have fun put one up front too.
If you have a chance to rework the back suspension, I suggest considering attaching the weight of the engine to the upper frame so that its weight will be helping in smothing the back suspension
running a panhard/track bar is going to push the suspension right under compression. you'll need a watts link to prevent that entirely. you could also weld the panhard on level with the rear subframe when the suspension is at its normal ride height wet (the heaviest the kart will be with you in it) so the effect will be less under full compression.
hi instead of using the panarod system use a watt link suspension it wont push the rear axle sideways when traveling thru its suspension travel also softer springs shroud do the trick, moving them on a 45 deg angle wont do a lot, cheers
Very cool videos. have you looked into free software cad programs you build great stuff and your ideas make sense. The cad building and testing on computer would be a cool and interesting addition .
Awesome as always man, ever thought about mounting the engine to the frame instead? and jackshaft it to the pivit point of the swingarm? ofc it would not work with this suspension setup but you know, for a build with a traditional swing, get that weight of the axle, would make for a much nicer smoother ride
I admire your ability to build a kart in what seems like just two weeks. When I was building mine, a day's work was assembling the spindles. It took me 3 months to complete it because I read whatever I could find on caster angle, camber, toe, unsprung weight, CV joints, kingpin angle and more in order to make a fine tuned car. I suggest you do more research because with your skills, you can make a professional-grade kart.
Are you using pipe or tubing? If you're using piping that is the reason its way too heavy, tubing is much thinner and is more than enough in the strength category.
its called valve float, over revving the engine causes the valve to not fully close before the cam comes back around to re-open it, and the cam or rocker smacks down on the spring before it back up into place, causing the valve to bind and in your case bind enough to bend, you tube valve float and see what its all about, and put this info in your video to teach others!
My solution to this would have been to tell you to remount the engine hanging off the top of the frame as opposed to sitting directly on the axle doing nothing but putting pressure on it. Those axles were perfect for the weight of the engine but you only had it supporting maybe 60lbs at most worth of frame.
You an use those shocks just mount them farther back on the swing arm and lower on the frame so it compresses it at a angle instead of strait up and down
Awesome build try bringing the top mount of the shocks inboard the cab to give you more of a 45 degree angle so you have more room second bring the top mount and rear bottom mount of the panhard bar closer to Center to minimize left to right movement you don't want the angle of the panhard bar to be very much the Strater you can get the panhard bar while you are sitting in the buggy the less actual movement you should have left or right on the axel derings rear suspension travel
That is an awesome idea for the suspension in the back. You should leave those stiffer shocks on there until you get to test it out. The only place that I can see that you could probably cut weight is from the sheet metal on the bottom part plus the Mufflers on those 670s are heavy. A light gas tank would help and I've got 2 670 go karts my favorite battery are the 1.3 pound lithium ion batteries Crank It Up great they're about 70 bucks on eBay. Or you could just jump it.
For taking the trails that you ride, you need much more lift, maybe 18" to compensate for rocks and for shock compression; and your power is not well managed by your transmission. Larger tires will help. Ditch the live axle and that crazy hinge arrangement for independent suspension. Make the sitting area a bit narrower. Hard mount your motor and transmission, and use independent axles. Encase all the drive gear in the frame, not hanging below it. You will compress the hell out of your back bone everytime you slam your butt against the ground. I've been thinking about a similar kind of buggy, but I have years of off-road experience and have seen some pretty wild buggies in my life. You will eventually work out the bugs and find a compromise.
The suspension in the back is so rough because all the weight is unsprung it will never work that well with all that unsprung weight...But it can still be fun.....cheers
Love the ideas man, the suspension set up looks like it makes the engine technically unsprung weight so it will not alter the spring rate. If the engine was attached to the main frame and it would effect the weight handling. This setup would make the suspension a little more complicated but I believe it would handle better. Also the panhard bar or track bar should always be made parallel to the deck as much as possible so you will have less of and arch it will travel through and make the handling less sketchy. Anyway I always find your vids inspiring. Thank you.
Probably softer springs or different shocks is the cost effective way. Though with more mounts, heim joints and a lever with a link to the suspension it could be softer and probably longer travel. That would probably exacerbate the links effect on rear steer which you probably have at this point (read down in the comments, watts link is probably a good idea, but hey its testing purposes maybe it'll be fine) . Cool series though, back to the popcorn and waiting.. :)
You should get some adjustable shock absorbers Spax do some ,or fit top mounting plates with multiple top mounting holes and fit 3 each side that are weaker altogether ? Check out a “Fugative” vw beetle based off roader , pictures and plans availcble free on line dude
So many people don’t understand levers with their comments about moving the shocks back to make it softer. You are all 100% wrong. The closer the shock mount is to the fulcrum (pivot point) the easier it will move the shock. Adding the engine will never soften the ride since it is unsprung weight. Only adding weight above the springs will help but your springs are too strong. Not the shocks. Your pan hard bar will cause you so much headache positioned like that if you ever get the softer springs. Easily check it by unbolting the bottom end and raise it up and check where it is relative to the crossbar. That’s how much your wheels will shift when the suspension compresses. When you order new springs for the back get a softer set for the front too.
1. the more horizontal your suspension components are the softer it becomes 2. switch rear setup to a double triangulated 4 link! you'll get the articulation you want and you won't have to screw with a whole hell of a lot of floating side to side. You can still run a panhard bar, but, it's also semi-unnecessary for something meant to be offroaded
