Predator motor , yerff dog , jack shaft , 30 series converter and cursing !

[Quietcoolguy]

Good evening
I am confused so I have a older yerf dog it has a jack shaft. I wanted to put a new 30 series on it but didn’t wana break the bank so I wanted to try a Amazon on to see how it worked snd if didn’t work the upgrade. Well kits has a plate ur supposed to mount on motor to use driven and driver pulleys. I was able to get the old driven pully off the jack shaft and put the new one on.. in order to get the front and rear Pulluys to line up I had to use to big spacers but there hardly any room on the shaft for the driver pulley (I guess the original motor he more more shaft.. am I doing this right ? Is it okay to have that little of shaft to set the driver pully on? Any advice would be helpful. I uploaded some pictures of the driver pully in line with the driven pully but u can see how much distance I have to space it out to get them to line up I don’t think I can move the motor over cause then it looks like the chain sprocket is gona come into play … ughhh

 

[ezcome-ezgo]

I am not an expert, but can't you flip the driven pulley around?

 

[madprofessor]

What a clusterflop! Never seen that one before. Looks like you've taken the 2 components of a torque converter (CVT) off of their backplate and installed them on your setup any way you could think of. Looks like a 30 series asymmetrical driven unit (fixed half is basically a flat piece) is getting paired up with either a 40 series symmetrical driver clutch (common V-belt has equal angle on both sides) or that piece of driver clutch is a 30 series sitting on the shaft backward.
Learn all you need to know before proceeding any further. Go to "gokartsupply.com", click on the square for Comet Drive Belts. It will show you diagrams and instructions for all you need to know. Keep scrolling down, there's several more diagrams, and at bottom of page is a long explanation you need to read.

 

[Quietcoolguy]

What a clusterflop! Never seen that one before. Looks like you've taken the 2 components of a torque converter (CVT) off of their backplate and installed them on your setup any way you could think of. Looks like a 30 series asymmetrical driven unit (fixed half is basically a flat piece) is getting paired up with either a 40 series symmetrical driver clutch (common V-belt has equal angle on both sides) or that piece of driver clutch is a 30 series sitting on the shaft backward.
Learn all you need to know before proceeding any further. Go to "gokartsupply.com", click on the square for Comet Drive Belts. It will show you diagrams and instructions for all you need to know. Keep scrolling down, there's several more diagrams, and at bottom of page is a long explanation you need to read.

No not exactly I ordered a 30 series off of eBay … the yerfdog had a jack plate that had the orginal driven pully.. I was able to get the original off the jack shaft and simply but the new eBay driven pully on

the pic I uploaded was a picture of the orginal driver pully on the shaft (guess I should have put the new eBay one for the pic ) but they are not that different I was more so showing the space from the back of the pulley to the engine that I have to make up to get the two pulleys to be in line with each other … it’s a lot! and once I put the spacers (it takes two of them ) I barely have any shaft left to assemble the driver pulley .. I’m gona leave work here is a bit and go put it together with the new eBay converter snd take some picks but thanks for ur response maybe once I show it with all the new parts you can relook at it haha one of the pics I uploaded isn’t even my go cart it was a screen shot of a YouTube video I was trying blow up to see how many spacers the guy used because he did the same thing I’m trying to do .. using the orginal jack shaft snd not using that bolt on plate

 

[Quietcoolguy]

Okay I came home and took some new photos to better show the buffudlement
Pic 1 is the new eBay 30 series converter with the mounting plate
Pic 2 is just the motor shaft with the two spacers
Pic 3 the two spacers on and the first portion of the driver pulley as you can see once I slide it up against the spacers it lines up with the driven pulley on the jack shaft but there is no room on the shaft after that
Pic 4 is a side view of driver pulley on the shaft and how little shaft there is
Pic 5 is where the driver pulley sits with jus on spacer .. as u can see it’s not aligned with rear driven pulley and has a ways to go to line up

so question is how do I get the new driver and driven pulley to line up and still use my orginal jack shaft … is that possible ? Do I need to change where jack shaft or motor mounting holes are ? Any help would be great

 

[madprofessor]

Alright Q, the shortest thing for me is just to say what I would do with the parts you already have, ie; a brand new 30 series CVT from ebay, same place I get mine. $52 for one, thinking $60 for another, then ?
(1): I'd move the motor over to the left 2"-6", then bolt the complete CVT to the engine, swung forward, straight back, hanging down, doesn't matter, then move and align the axle sprocket to CVT sprocket.
(2): I'd cut either a part of or the whole jackshaft off to get it out of the way, then bolt the complete CVT to the engine, again the configuration doesn't matter, then align the axle sprocket to the CVT sprocket.

There you go, I'm saying you don't use the existing jackshaft, you use the shaft on the CVT, and you move the axle sprocket.

 

[Quietcoolguy]

Alright Q, the shortest thing for me is just to say what I would do with the parts you already have, ie; a brand new 30 series CVT from ebay, same place I get mine. $52 for one, thinking $60 for another, then ?
(1): I'd move the motor over to the left 2"-6", then bolt the complete CVT to the engine, swung forward, straight back, hanging down, doesn't matter, then move and align the axle sprocket to CVT sprocket.
(2): I'd cut either a part of or the whole jackshaft off to get it out of the way, then bolt the complete CVT to the engine, again the configuration doesn't matter, then align the axle sprocket to the CVT sprocket.

There you go, I'm saying you don't use the existing jackshaft, you use the shaft on the CVT, and you move the axle sprocket.

Okay I was hoping to use the jack shaft but it simply is held on by only two bolts snd it comes off pretty easy … I had another yerf dog like the one I have but traded for the one I have now because the front had been modified and I didn’t want to deal with it , so the guy had a few let me pick another frame … but I messed around with the rear axle of the first one and mannnn messing with that sprocket is gona be a damn night mare … for one they rust and freeze on the shaft and second they are held in place by a series of snap rings on either side so it doesn’t slide on he axle (took the first one to a machine shop and have to have a 30 ton press pop the snap rings off lol to get the sprocket off … I starting to look like I’m gona have to make new motor mount ughh I’m gona try what your talking about and see how far off the sprocket and cvt chain cog are out of line

 

[madprofessor]

Some folks have left a frozen sprocket in place and slid on another one next to it, rather than fight the old one over just to end up with same number of teeth you had before. (Not necessarily a ratio that fits your planned application.)
Personally I'm a big fan of sprocket hubs with quick change split sprockets. Never slide a sprocket on again. My particular hub has a split in the core with a bolt to squeeze it tight to the shaft, so it holds tighter and would always come loose later if desired.

 

[Quietcoolguy]

Man I like the idea of a sprocket that will come off easy .. these yerf dog sprockets not only have bolts that screw down against the shaft they have those god awful snap rings … I never new a snap ring could be so strong the place I took it to had an old 30 or 60 ton press and the first time he pushed down on the sprocket one side of the press came off the ground … I was like damn a snap ring holding that strong .. he said yeah on some hydraulic cylinders only a snap ring holds em together but it couldn’t stand up against that old press … but I’m actually walking out to my garage to work on setting it up without the jack shaft.. I moved the engine over last night and I had room when I did get the pulleys lunged up (maybe off a hair) but man the chain was to close to the engine housing for my liking so cvt ans engine plate it is

 

[Denny]

I have a feeling that kart originally had a 20 series cvt on it. So the 30 series will not fit without modification. You do not use a 30 ton press to remove snap rings. You use snapping pliers.

 

[Quietcoolguy]

I know I know haha but I did not have have said snap rings pliers at my moms. I went for a visit and had the axle in back of the truck. The sprocket and bearings had rusted on that axle and the metal shop guy just over powered the snap rings but man I never thought a snap ring withstand that much force for as long as it did …. Sooo update

Me and my uncles who don’t have any give up in us worked on it during 4 of July cookout . I took ur advice and used the engine plate that came with the kit . Alignment is just a touch off between the pulleys but close enough for government work lol.. I got converter on and belts but to be honest the engine just didn’t have enough get up and go for me… sooo a few YouTube videos later I’m disconnecting the governor rod , drilling a hole in the throttle arm , bending and cutting said old governed rod , and whala! Lol … engine is prime and ready to rock and roll.. installed a longer screw for the throttle stop so I could adjust it further than the factory one so my kids wouldn’t kill themselves no blow the engine to kingdom Come lol and the yerfdog is alive!!! Thanks so much for the help…I got fix the tire rods and a few minor things but it enough they got to ride it … but I got install the seat belts and till cage back before my kids become a damn insurance deductible waiting to happen..
Truly thank you for ur patience , help and humor .. if ur ever in Richmond Va let me know I owe you a beer !! … now I want to build me one for myself and put big predator engine on it … and I already have two 650 Kwai brute forces that will flat out scare u to death but the go karts are just fun to drive … take care!!!

 

[KartFab]

Yerf dog runs a 7” driven. Run the sprocket on the outside of the jackshaft and relocate axle sprocket.