Hello from Iowa. My sons and I have been getting into dirt bikes and wheelers lately. We got a 1983 yamaha 80 that we rebuilt after sitting in a basement for the last 9 years. We also acquired a frankenstein wheeler with a suzuki gs500 streetbike engine in it. Both projects are up and running tearing up grandpas farm. The boys and I have decided we are going to build a little yard kart out of all my father in-laws broken down riding lawnmowers, scrap metal etc. After a lot of research on my part I am noticing most karts are built in the 5hp-10hp range with horizontal shaft motors. We have 3 motors; 25hp tecumseh ohv vertical shaft ( the only one we have torn apart), 22.5hp something, and a 19hp something 'er other. All of them are vert shafts and seem to be a little much for what we were originally going to build. We are ok with building something a little more suitible for the engine size but I'm not really sure where to begin. Rebuilding our past projects were mostly simple since we were just replacing the bad parts and cleaning the good ones. This or these projects are going to be designed from the ground up by a carpenter, 9th grader, and a 5th grader. I'm mostly worried (for now) about the size of the engine and the weight of what we build. I don't want to build a slug and mostly don't want it to be too light like our original plan. Very unsafe. I think if you guys can help me decide how big we should build it. Single seat / double? Wheel base...Volkswagen bug size? I am sure I will have many more questions as the build progresses like drivetrain, suspension, should I use a RAGB etc, but for now I'm just trying to figure out the size. Off topic if anyone needs advice about DIY home improvements I have 15 years experience in the home building and remodeling field. Thanks for the ad and I look forward to bugging everyone with potentially very noob questions.
Iowa
- Thread starter jasonH
- Start date
- Status
Poboy kartman
Senior Moments Member
Welcome to the forum and please fill out your profile so we will know you're from Iowa in future posts.
First bit of advice....forget trying to use those engines....get a HF Predator and save yourself the headaches and expense involved.....it will be many times cheaper that way....and much easier to build....
A little bit like building a cement block house because you have them...you ought to understand that analogy......
First bit of advice....forget trying to use those engines....get a HF Predator and save yourself the headaches and expense involved.....it will be many times cheaper that way....and much easier to build....
A little bit like building a cement block house because you have them...you ought to understand that analogy......
Profile is updated. Thanks. I have sketched out a rough draft of our plan on a cocktail napkin. I hear that's how the pros do it. I had a $200 RAGB with a 1:1 ratio that could handle 25hp and 3600 rpms. After that in the line I have a centrifugal clutch that could handle the 25hp as well, also with a $200+ price tag. I haven't made it to the research of using belts or chains. I also have not made it much past that in the design. I stumbled across a website that said a 25hp motor is roughly 625cc and got me concerned about the frame design. I understand that this will not be an easy project nor cheap but would like to at least see the design through before I scratch the plan.
I did look up the HF Predator. In my experience Harbor Freight sells throw away tools. Is there a reason to buy that one instead of other 6.5's? Can you help me understand in more depth as to why you would ditch the vert shaft and buy a 6.5. What kind of problems will I run into if I build with the 25hp?
I did look up the HF Predator. In my experience Harbor Freight sells throw away tools. Is there a reason to buy that one instead of other 6.5's? Can you help me understand in more depth as to why you would ditch the vert shaft and buy a 6.5. What kind of problems will I run into if I build with the 25hp?
firemanjim
Just kartin' around....
Why buy a predator from HF? Well, hmmmmm
Cause for a $100 for the engine, and a couple hours work, I end up with a fire breathing 10-12hp engine...... I have a couple. And I have a Honda gx160. I think I like the Predator better, even though my gx is modded to at least 9+ hp, and my predator is stock, minus the exhaust.
HF does sell slightly useful tools. But that predator is a diamond in the rough.... IMHO,it's the best clone made, next to maybe a Lifan. It's stroked and poked right out of the box.... 212cc's, where the other clones you see, you get like 196cc....
It's what we all use.... Would all of us lie to you?
The vert engine CAN be converted to a horizontal engine, but it's a hassle. Using it as a vert shaft, pita if you ask me..... I'd sell what you can and buy TWO predators, hop them up, and buy 2 good knock off tc's, then build 2 karts..... It's almost the same money and hassle as what you think you want to do.... Personally, I don't like headaches, so I go the simple/most effective route.....
Use those type engine to build YOU a "racin mower"......
Cause for a $100 for the engine, and a couple hours work, I end up with a fire breathing 10-12hp engine...... I have a couple. And I have a Honda gx160. I think I like the Predator better, even though my gx is modded to at least 9+ hp, and my predator is stock, minus the exhaust.
HF does sell slightly useful tools. But that predator is a diamond in the rough.... IMHO,it's the best clone made, next to maybe a Lifan. It's stroked and poked right out of the box.... 212cc's, where the other clones you see, you get like 196cc....
It's what we all use.... Would all of us lie to you?
The vert engine CAN be converted to a horizontal engine, but it's a hassle. Using it as a vert shaft, pita if you ask me..... I'd sell what you can and buy TWO predators, hop them up, and buy 2 good knock off tc's, then build 2 karts..... It's almost the same money and hassle as what you think you want to do.... Personally, I don't like headaches, so I go the simple/most effective route.....
Use those type engine to build YOU a "racin mower"......
I am a big fan of the KISS concept. I completely understand how simple a kart from a predator engine would be. Most of the research I have been doing for the build is coming from "racin mower" sites and forums. For the build, I was thinking of using their princibles and how to's. And adapting it to a buggy style build. I think I am going to use the other 2 engines to sell and buy a couple of the predators for the yard karts. I am going to go through with the design, expensive, and long process of the build for a buggy. A couple of questions for you... What are " knock off tc's? Can I use the frames from the riding mowers, modified slightly of course, for the predators? I was thinking of re-using as much as I can; steering, suspension, seat, fairings, rims, tires, lights, and a partridge in a pair tree. Thanks again for all the info.
firemanjim
Just kartin' around....
And knock off tc is anything other than a Comet brand or Max-Torque brand torque converter. It's a simple transmission for a small vehicle. They are used on everything from go karts to big side by sides.... The JD gators use them.... Gas powered golf carts use them.... They are great.....
A knock off would be like the Blueline brand or GTC brand, and the ones that don't have a name. The GTC brand I hear is pretty good. One of our members bought the $120 no name knock off and has had no major complaints, AFAIK......
As far as the mowers go.... You can use the frames, but they are just too dam heavy to be any fun. I know you can build a much better platform for these buggies. You'll be unhappy with the weight.... The racers get away with it cuz they're using higher hp engines..... Everything else though, you could use.... Except the front steering components. They were not meant to be used at a "high speed" and therefore will not work/preform like you want. It would be better to buy or build the correct components needed. It's a safety thing, really..... You want that stuff to crack under pressure as your kid is making a "high speed " slide? Uhhh, no..... You want the right stuff here.....
A simple suspension kart isn't that difficult. Just a swing arm rear end..... You got shocks ? Good, now go buy some pivots, or big hiem ends to make a suspension kart.....
We will help you with what ever info you need, advice, ect.... I'm pretty sure you can tackle the job, or you wouldn't have said anything to your kids. I hate disappointing my kids....any kids..... For that matter.....
What else you need to know?
A knock off would be like the Blueline brand or GTC brand, and the ones that don't have a name. The GTC brand I hear is pretty good. One of our members bought the $120 no name knock off and has had no major complaints, AFAIK......
As far as the mowers go.... You can use the frames, but they are just too dam heavy to be any fun. I know you can build a much better platform for these buggies. You'll be unhappy with the weight.... The racers get away with it cuz they're using higher hp engines..... Everything else though, you could use.... Except the front steering components. They were not meant to be used at a "high speed" and therefore will not work/preform like you want. It would be better to buy or build the correct components needed. It's a safety thing, really..... You want that stuff to crack under pressure as your kid is making a "high speed " slide? Uhhh, no..... You want the right stuff here.....
A simple suspension kart isn't that difficult. Just a swing arm rear end..... You got shocks ? Good, now go buy some pivots, or big hiem ends to make a suspension kart.....
We will help you with what ever info you need, advice, ect.... I'm pretty sure you can tackle the job, or you wouldn't have said anything to your kids. I hate disappointing my kids....any kids..... For that matter.....
What else you need to know?
getting ready to purchase 2 predators but notice there are 3 different ones for 6.5. any idea what item number? i was looking at this TC as well http://www.ebay.com/itm/Predator-21...2-218353-/181511438064?_trksid=p2054897.l4275
thoughts?
thoughts?
I noticed the #69730 is 12-1/2" long and the #60730 is 14-1/2" long. That was the only difference I could see between those. The 60363 is 12-1/2" long but in the pdf manual it has a rating for speed/idle that is different from the other 2 engines. it says 1,800±150rpm when the other 2 have speed/idle rated 1,800±50rpm. What does that mean? Why would one be 2" longer than the other?
jeeperjoel
New member
does the 2" longer model have electric start?
firemanjim
Just kartin' around....
Get the 60363.... It's the hemi...... Don't worry about idle speed.....
Welcome
Well, They were on sale last night for $90 a piece. With the sale ending last night I prematurely hit the purchase button (before I heard back) and bought 2- 69730's. I am assuming all will still be good with these.
Thank You
firemanjim
Just kartin' around....
You're ok with all of them except the California models...... (just an epa pollution choke hold tyoe thing..... ) 
Wow!! $90!!! Should been "shopping" myself......
Wow!! $90!!! Should been "shopping" myself......
Poboy kartman
Senior Moments Member
Unfortunately.....it's really,really bad luck to own two of that paticular model # engines at the same time.....
So....I suggest you send the extra bad luck offender to "The Poboy Fund" C/O White Settlement...Texas......
So....I suggest you send the extra bad luck offender to "The Poboy Fund" C/O White Settlement...Texas......
You're ok with all of them except the California models...... (just an epa pollution choke hold tyoe thing..... )
Wow!! $90!!! Should been "shopping" myself......
Hope I didn't get those!!!
I think I have a decent design going here. I have the predator 6.5 attached to a OMB #40 10 tooth TC and a 60 tooth axle sprocket. 19.5" rear tires, not sure the fronts. I'm not sure what they call the front suspension with a "c" bracket and a spring in there with a through bolt. Using Tie rod steering. Going to make the frame out of 1" square since I don't have access to a bender. I have a question about the front suspension springs and the rear suspension. What kind of springs are on the front? The rear suspension I was thinking about using a couple of shocks with 2" of travel. I have noticed in a lot of other builds the tires and drive assembly is on a separate frame that pivots at the base of the kart frame. My questions are; Does the engine get mounted on the stationary frame or the frame that pivots? and #2 how does the chain stay tight when there is 2" of travel in the rear axle? I apologize in advance If you have answered these a hundred times over. This forum has been very useful. If I couldn't find it here I would google it, which mostly brought me right back here. With any luck I'll be welding by Christmas.
firemanjim
Just kartin' around....
There is 2 options used..... Both are considered swing arm rear ends....
First, you have the engine mounted to the swing arm. It is considered unsprung weight because the engines weight is on the tires and not the shocks. The chain always keeps the same tension because the engine and axle move together.
Second, is a "sprung" weight design, where the engine is mounted to the frame and stays stationary. The chain from the engine, drives a sprocket that is on the same shaft the the rear swing arm pivots on. A sprocket next to that one, drives the axle. As the suspension moves up and down, the chain tension stays the same.
Does that makes sense....? That's like the 5 minute version.....
First, you have the engine mounted to the swing arm. It is considered unsprung weight because the engines weight is on the tires and not the shocks. The chain always keeps the same tension because the engine and axle move together.
Second, is a "sprung" weight design, where the engine is mounted to the frame and stays stationary. The chain from the engine, drives a sprocket that is on the same shaft the the rear swing arm pivots on. A sprocket next to that one, drives the axle. As the suspension moves up and down, the chain tension stays the same.
Does that makes sense....? That's like the 5 minute version.....
Yeah, makes sense. Thanks. It looks like swing arm mount is the mount for me. Once I start and have something to show I will post a new thread. Thanks for everything so far.There is 2 options used..... Both are considered swing arm rear ends....
First, you have the engine mounted to the swing arm. It is considered unsprung weight because the engines weight is on the tires and not the shocks. The chain always keeps the same tension because the engine and axle move together.
Second, is a "sprung" weight design, where the engine is mounted to the frame and stays stationary. The chain from the engine, drives a sprocket that is on the same shaft the the rear swing arm pivots on. A sprocket next to that one, drives the axle. As the suspension moves up and down, the chain tension stays the same.
Does that makes sense....? That's like the 5 minute version.....
Adjustable seat and steering design
I was thinking about doing an adjustable seat and steering since my boys are very different heights and I am sure the adults will want to play also. I was thinking of something like this sketch. I have plenty of T-track for the seat laying around with knob bolts (4) and was thinking of using trailer hitch pins for the steering shaft (2). Has anyone attempted this? If so were there problems to overcome? Any other flaws in my design?
I was thinking about doing an adjustable seat and steering since my boys are very different heights and I am sure the adults will want to play also. I was thinking of something like this sketch. I have plenty of T-track for the seat laying around with knob bolts (4) and was thinking of using trailer hitch pins for the steering shaft (2). Has anyone attempted this? If so were there problems to overcome? Any other flaws in my design?
Attachments
-
20141211_120047.jpg
- Status