[FINALIST] - CraftsmanQuad's CraftsmanQuad Mark II [2019 buildoff entry]

CraftsmanQuad19 wrote:

Currently welding the front suspension up. I’ll be honest, I just eyeballed where I think it should go haha

Eyeballing is A-OK.
This thing's going to Haspin, not to outer space... Although I'm not sure which environment would be harder on the equipment.

LOL, AK is worried about spacing, I'm wondering where the top of the shock towers are going to go!  

@MightyRaze same lol this is why my motor is backwards

Actually it all just barely fits below the cylinder head/valve cover. I was surprised it all fit so well honestly, I figured it would be a major pain. So far my design seems simple and effective, but we will see how the whole thing transfers to the wheels on the ground and weighed down with the engine and me

@CraftsmanQuad19 you must have those really short crappy coil overs then? Mine being almost 15 inches long I couldn’t get around the juggs

Yeah they’re pretty junk, however, they’re better than a solid stock style axle with no suspension at all. They’re very springy and have a lot of rebound, but adjustable preload. Hopefully they work well enough until I get some nicer ones of similar dimensions

Edit: I just measured the length of the shocks and eye to eye is just shy of 11 inches with no load at all. Came off a Chinese quad so I believe they’re metric, but should be able to find some shocks in a similar size pretty easy.

AllisKidD21 wrote:

Nice job on those welds! Nice to see it all hanging on the frame, pretty cool.

The geometery however looks a tiny bit off to me, in relation to the pivots on the king pin vs the A-arms mounts:



It might only be the picture making it look worse than it is, but it looks as though the pivot points are closer together on the mounts. I would think that would cause the wheels to camber in a bit throughout up travel because the arms are, in theory, not traveling the same radius. Might not be so good at high speeds..

Like I said though it might just be the angle of the picture screwin' with me, haha. Sorry for any confusion.

Every sport quad that I ever messed with was like that (but I don't want to say every one is like that cuz I really don't know. But if I had to guess I'd say they are. But that goes for sport quads only I think utility quads run their a-arms parallel apart from each other or [equally spaced apart vertical pivot points].)

Years back when I was getting into flat track atv racing I asked the head honcho of the atv shop that we raced for awhole bunch of questions on the suspenion setup of a atv. One of them was "why is the inner pivot points closer together than the outer pivot points."  

His answer was -
The a arms when traveling in their cycle of motion don't travel straight up and down they travel in a arc.  The KPI is set by the different lenght of a arms (between the upper and lower ones) and the ball joint mounting points on the spindle. [And on some atv chassis I've seen different lenght of a arm mounting tabs between the upper and lower ones.]  

There are 2 main a arms setups. Parallel and Unparallel.
Parallel - the KPI stays the same through the a arm cycle
Unparallel - the KPI will do an arc through the a arm cycle. The arc radius will vary by how much of a difference there is between the pivot points and the arc direction will vary by which pivot points are offseted in what direction they are offseted in.

On sport quads because they got no real weight on the front suspension they run a offseted or unparallel a arms setup.
Then because quads don't use any form of sway bar  there is the whole thing on equal but opposite reaction. When entering a turn with a little bit of speed one side of the front suspension is being compressed while the other side is uncompressed and lighter than sprung weight.  By having an arc in the KPI as the a arms compress it allows the tire's edge to make contact with the ground to (bite in) and allow the steering to hook up better.


Hope that made some sense.  i know I left out a bunch of other info and important tidbits but all I wanted to do was skim the basics. Just remember this came from a shop guy not a atv frame designer, i feel it's correct and makes sense but I've been wrong before.


@CraftsmanQuad19
Your build looks great. Should be a huge improvement from your last one.
Do you happen to know the spring rate on your shocks and the weight of your mower front end?   And also the amount of travel in your shocks?

I’ve got no idea what the specs are on them. They’re just original shocks from a Tao Tao 110cc mini atv. But yes your explanation was quite good, I never thought about the absence of a sway bar so it would make sense that the camber would make up for it

Yeah that does make sense that it would help when taking a hard corner rather fast. I didn't really think about that, haha.

My bad!

Might’ve weldedthe a arms a bit too high on the frame....hopefully bigger front tires will compensate some. They’re spaced really far out so I’m not too worried about hitting the frame when I turn. Rear fenders definitely need trimmed though...




Hard to tell exactly where the rear wheels will go since the transaxle isn’t in it right now, this is about as close as I could eyeball it

Looks great man! Are going up to 18s in the front? Not to be pushy or anything because you should build it however you want and do what agrees with your budget. But I think you should live axle swap the 820. Now that the front end is nice and wide I think it would be nice if the rear was widened out to match and adding some strength wouldn't hurt either. Just my personal opinion. But above all build it how you want it!

Also: Do you have 8in rims with a 1in bore like off a go kart or something? Or do you have 4 on 4 rims with hubs?

Actually I was going to do the live axle swap eventually, but won’t be before haspin. For now I’ll weld the diff and run it till it breaks. I actually mentioned the live axle in a video I filmed tonight but haven’t posted. I’ll probably do that tomorrow.

I have the hubs from the atv the wheels came off of but they’re splined and my 1 inch drillbit absolutely sucks. I think I’ve got a 1 inch hole saw at school imma use to hog em out. Just have to take the teeth off. Then they need broached and the rear hubs will be good. Yes I’m putting bigger wheels and tires up front, but I don’t recall the exact dimensions at the moment. They’re the matching pair to the rears though, but narrower. Potentially even an inch taller. I’ve always loved the look of equal sized tires on a mower that still sits level, now I might finally have it!

I’ll post the video here just as soon as it’s uploaded

LOVE THAT RIG!!!!

Just look at that stance!

hmm U need to widen its Ass as well, or it looks kinda strange! But the Front End starts to kick ass!

The rear will be widened with the solid axle whenever I get to it. That won’t be for awhile though. Probably mid summer honestly. I’d really like a chromoly axle so I’ll probably save and do it right and doc lock that. For now I’m doing a combined fozzy/fearless locker just to make it to haspin. I’ll run it till it either breaks or I get tired of the narrow stance.

Currently trying to upload the video from last night, please standby.

As promised, here's the video!

Looks good. Front looks mean, LOL. With the rear end narrower then the front, as it is now, will turn easier with it locked in the rear. Just something to think about. Might not want to give up the easy turning for something that would look better. More of a function thing then a looks thing.

prancstaman wrote:

Looks good. Front looks mean, LOL. With the rear end narrower then the front, as it is now, will turn easier with it locked in the rear. Just something to think about. Might not want to give up the easy turning for something that would look better. More of a function thing then a looks thing.

Isn’t that why most sport quads (live axle swingarm with chain drive) have a narrower track width in the rear? I may run the rear track a little narrower than the front to help keep stress off the transaxle, but they will get widened out some. May end up widening the fenders a bit to fit them better but we will cross that bridge when we get there

Nice video CQ! The drum brakes on the front should be pretty sweet!

Kind of a funny thing about having a wider track width on the front is that, when squeezing the fronts wheels through trails, you always know the rears are gonna clear as long as the fronts do. Haha.

prancstaman wrote:

Looks good. Front looks mean, LOL. With the rear end narrower then the front, as it is now, will turn easier with it locked in the rear. Just something to think about. Might not want to give up the easy turning for something that would look better. More of a function thing then a looks thing.

Well the main advantage is stability but with the lowered seat and wider (non articulating) front end thats less of an issue. But that aside a live axle conversion is a great mod and by sacrificing width you gain strength.

Just whatched the video everything looks awesome. I also am not a huge fan of the tunnel shifter. My main issue with it is the stiffness and slow shifting. This may because I run Spicers and they are notorious for there poor shifting.
The shocks should serve you well. Although the kind that redzz02 used may be higher quality I think you will get more travel out of the cheap coil overs.

Good Video! U WORKED HARD!

Thanks for the kind words everyone! Prom is next weekend and I need to focus on getting the impala running so I can put some miles on it before I drive halfway around the state haha. Progress will be slow this week through next weekend. Once the impala is running I can focus all my resources in this thing so I can put some time on it before haspin. Do some “durability testing” haha

Updates will follow!

The slap shifter and front drum brakes are great additions. Front brakes are going to come in really handy on downhill descents at Haspin.

Yes like Carl said the front brakes are going be amazing. Since rear brakes provide little stopping power that is going to be a world of difference.