Newbie with a yammy 750

[Durangokid]

Hey hows it going? My names mason, im 18 and a student at wyotech. Theres nothing to do out here in Blairsville, Pa so I started brain storming ideas for a toy to build. After going on Youtube I found it. A motorcycle engine in a buggy. Next week im picking up a 750 3cyl yammy motor, and I ordered a harness off ebay for it. I have the know how, and welding skills, and access to some quad parts. Im trying to get this done for as CHEAP as humanly possible, but FUN as hell. Any advice on how to start a nice frame would be AWESOME!
Thanks in advance!

[Durangokid]

I found a site and I was reading and there is a picture of a body and frame from a company here in PA, thats CHEAP. and I think it would make an awesome base for my project
let me know what you think.
TheSamba.com :: View topic - Who makes a go cart size dunebuggy body?
O and I forgot to mention, I have a IHI turbo for it as well hehehe

[nutz4sand]

The body would add to the cost and the weight. If your willing to pay that for the looks then its your thing do it your way (not affiliated wtih Burger King...) Plus you gotta cut tube holes in it or build around it.

As for know how you need to make sure you understand front end geometry before anything else if you want it to ride and handle anything like good.

A good design will start with the wheels and tires then build the spinldes to match those for proper king pin Inclination and the ackerman you wish to have. This is also the time to set up the caster and camber curves and the spindle design reflects all of this.

Once the spindles done you fab the arms then go inward to the frame.

The frame should be the last thing you design.

Or buy plans of a proven design and follow them.

You can by a frame or frame kit off someone and build from there. People do it all the time. But you have to be willing to make any compromises that particular frame may have in the way of just what you may wish to do.

[Durangokid]

Yea, the plans have changed. I found a 2 seater go cart with no motor that I want(as long as it has a full cage like the one seater he has pictured). I wanna put a IRS rear end from a quad, and a front end off a quad on it, then then 750 in the back.
What do you guys think of that plan? Im getting the motor and harness for like 90 bucks, and im hoping to get the whole go cart roller for 100 bucks.
im up for ideas from you guys, I just want something fast that I can take on and off road while im in college. Plus its a project to keep me out of trouble.

[nutz4sand]

Pictures of the frame to try to judge its abilty to hold the 750 would be a start as well as the power this particular 750 makes.

Out of trouble...On road buggy... I see a lil conflict of interest here! lol

[Durangokid]

Originally Posted by nutz4sand

Pictures of the frame to try to judge its abilty to hold the 750 would be a start as well as the power this particular 750 makes.

Out of trouble...On road buggy... I see a lil conflict of interest here! lol

Well its mostly gonna be a offroad one. I want to do a IRS and IFS, its got a full cage, its a 79 750 3cyl.

im trying to get a set of 250r spindles, a arms, rotors, and hubs off ebay

[voodoochikin04]

be careful.. is it a 750 special? probably since its a 3cyl... those engines hate high rpms.. i think they redline at 8.5 or 9.. in a buggy, with the low power the engine makes and the gearing you would need in order to tear around, you would have to be running higher rpms all the time in each gear in order to get pushing along.. ive personally had these engines pop on me before. i would recommend finding a 4cylinder.. those 750's also have very strong records of killing the second gear, gear dogs.. and losing 2nd gear. just some advice from someone who has dealt with these engines before.

[Chikin1974]

Well A 750 motor in a 2 seater gocart frame would be FAST but being safe on a budget with a rocket can be a conflict. I hope that you make a cage that can protect you and a PASSENGER. Post video of this when its done.

[voodoochikin04]

its not a rocket!! its a 1979 yamaha 750 3cylinder engine. those engines dont have squat for power.. and they are prime to blow when ran alot at high rpms.. and for a 2 seater.. the frame plus rotating assembly(axle, brake, wheels & tires) plus weight of two people is alot to push around for that engine unless its geared high, which in turn would mean high rpms all the time while driving..

[K-fab]

I'd guess that engine put out about 45 hp new. Not a rocket at all.