What's up everybody, i'm john i'm isaac and i'm charles and today on cars and cameras, we are working on the rice, wrong channel, going get scrambled all right, guys, i'm sorry about that. I don't know how they keep getting in. Here i mean we put locks on the doors we keep changing them, but they're always in here, but today we're going to be working on the rotary atv. So we'll give you a little recap and let's get started, as you all saw in the last videos.

Our pulley system was a really big problem for us we're having the belt slip. The pulley would just kind of open up immediately and we're just having a lot of issues and there's not really many parts to rebuild them or if there are they're super expensive. So what we wanted to do was switch to the go power sports supplied tav780. So google powersports has this people use them all the time on their 670s and just 30, 30 plus horsepower builds and they hold up great.

So we were super excited to use this. The only problem is the shaft on the rotary is a tapered one in ten tapered shaft and go power. Sports only supplies one inch shafts for the tab. 780..

So we have a machine shop. I'm a mechanical engineer at texas, a m so um. I have access to machine shop, so i made this adapter for us um it actually the fit, and everything was perfect. You know you can just slap it on and then 780 slides on very nicely very good fit the key weight.

Just snaps right in the it has a really good fit. Actually, okay. Well, there we go um. The only issue is i made this out of aluminum for some reason.

I don't really know why i probably just feels easier to machine, but you know we're getting thinking about this. We got some plans to make some more power on this, and i did we didn't think the aluminum could hold up so another problem. You can see with this, is it just sticks out insanely far, it's actually only about two centimeters further than the stock one, but i mean, as you all can see. I mean your foot's gon na be right here.

It's just like it's too far. It's also gon na put a lot of extra stress on the output shaft for the rotary, so what we ended up doing is getting the comet. This has the tapered shaft and everything. So this just fits right on and we'll do it exactly as we need.

It's a lot wiser to use this comet. I mean hear that looks really nice, it's just it's just a better fit, so here's our size comparison for everything, the stock. One is absolutely massive. This thing really stuck out, and unfortunately, after we made the adapter shaft and everything the new one we were going to use, was about a centimeter further out still.

Obviously, the duster is our clear winner, and this thing is pretty great and they're also known to be very tunable, so we should be able to get some good performance out of this as well. The only issues now is that we have a different belt and everything and we have to face the pulley. This way still so we have to do a new jack shaft setup and we'll go walk through that. So here's what our jack shaft setup's, looking like uh, we're pretty happy with it.

We're using these adjustable jack shaft mounts when we go power sports so we'll be able to slide forward and backwards and tension our belt and then we're gon na use. Two more of them to do another jack shaft in the back and we're gon na have to position that. So you know our chain just goes from the jack shaft to the back sprocket. So all the jack shaft mounts are tacked in it's looking a little bit busy back here, but honestly, i think it looks kind of cool with all the jack shaft mounts um, so yeah.

All we got to do is kick on the old hobart and start welding. This stuff and we'll see how it runs after that all right. Here's the moment of truth to see if everything's still lined up after welding it that just slides in there the bearing goes in the back yeah. That looks good.

It's pretty straight through the driven pulley and then into the sprocket for our second jack shaft to the other. Bearing there we go. Okay got ta, get that sweet all right. It's really close right here.

We may have to do a little bit of clearancing, but i mean we're going to have you know belt going to here and that's going to our jack shaft, which goes out to here, which then goes to the 50 chain, which goes our sprocket. I mean honestly. I think it feels really solid, so we got to use our little harbor. Freight mini lathe for the first time picked up a facebook marketplace for pretty cheap and we needed to shave down the locking collars, because the problem is our carb made.

Our bearing hanger have to be at a certain position and we're just running into some clearance issues. Okay, drive train is all buttoned up, we're just tensioning the chain. It's pretty nice, so chain barely touches the swing arm and then, as soon as you sit on it put any weights. We have nice clearances everywhere.

I'm pretty happy with this. Now, oh dude, the belt's like really slipping just did a bunch of work off camera, but now our torque converter setup should be perfect. The issue we're running into is that our um, the center line distance, which is the distance between the crankshaft and the jack shaft, was too far, so our belt was kind of too tight. What we ended up having to do was lengthen these jack shaft mounts right here and that just allowed us to get the pulleys a lot closer um other than that we added brakes, so we now have rear brakes on this thing, so the braking should be much Much better and all that's left to do is test drive this thing.

So let's see how it does so. We had problems with their clutch, not engaging when we started revving it up. We had to rev it up past, like 4 000 rpm, so we ordered our new clutch weights, so the comet 94c comes with extra slots and we can just slide these in here. We can just slide these in here super easy, and this should make our clutch engage quicker, so at a lower rpm, we should start grabbing on the belt now that our extra weights are in we're going to also re-gear this thing.

So i did the calculations for the gear ratio, and this is not including the torque converter. Our gear original gear ratio was from a 12 to a 14 on the jack shaft and then from the 12 on the jack shaft to a 41.. So if you multiply those two gear ratios together, that's a 3.99 and a lot of times. Go-Karts are running five, six, seven, eight or more, so we wanted to really increase the ski ratio.

Just to give this thing a lot more torque, especially since rotaries, are known more for horsepower and not torque. So what we're going to do is change the 12 to 14 to a 10 to 20 and then change the 12 to 41 to a 10 to 41, and that will give us a gear ratio of 8.2. So that is over double and should give us a lot more torque and we should still have plenty of top speed and we can always change this later. So right now everything's a little bit loose, but we have our 10 down here.

So we changed it to 12 to a 10 and we're keeping the same 14. I have to weld up this 20, so i just want to test it before we do anything just to see what it's like, since this is 40 chain, we'll have to redo the chain and everything, and then this 12 was changed to a 10.. So we have higher gear ratio here and a higher gear ratio there and we'll also be able to add this to get even more gearing. Another thing we're going to do is switch out our 780 for a 790..

The reason we're doing this is because the way go powersports has their backing plate set up it's. So it's super easy to mount on a 670 or 420 cart for a predator engine. The thing is: we're running ours. Inboard like this, while on the backing plate, it's normally like this, so the spring in this one is backwards.

So what we want to do is we'll just take this out and use it on a later build. But for now we're going to swap this out for the 790, which is the same radius and everything and that'll just sit right in there should be plug and play, and we should be going a lot better with our driven pulley yeah. That is so much better. Um there's a ton of slop in the chain, which is why it's super jerky, but that is a real working.

Torque converter. It was a combination of everything driver driven, gearing all right, uh nice still getting used to this thing need some wheelie bars. I know um dude, i'm i'm really happy. This is like the first time i've laughed driving to build in a while.

This is this is a blast now well after the top speed, i'm still pretty happy with this thing. It kind of works like a 30 series. Non-Juggernaut torque converter, so it doesn't really like shift super hard and kind of just keeps pulling at the top end. But i mean this thing's definitely really fast and i feel like if you just kept on the throttle, probably going like 50 60, maybe even 70, which is enough for us.

The wheelies are fun enough and you know being able to go fast is also pretty cool. Super happy how this turned out our chain, just as tight as when it started, we did see our exhaust was going a bit so we'll have to add some shielding on that, but other than that. We're super happy and thank you all for watching. Thank you.

Go power sports all of the jack shaft set up, which was super important for us to be able to do. This, swap is from good power sports, so make sure to check it out. Their jack shaft sliders are great, and thank you all for watching and thank you for subscribing see you next time. Um good.