MadDogRC

hey all,
as a school project we have built a petrol/nitro powered dune buggy and we eventually plan on racing it some day when its done, which is a long while since its all hand made and no books or anything to work off. we still got our alum wheel hubs to work on, body frame, new roll cage, NOS kit, paddle tires, etc. so far the current and favourite upgrade is my fully custom made exhaust which i designed completely and built all by myself.

its been about 8 weeks or just under know since i began creating my creation of ultimate power as the stock exhaust was crap, plus kept back firing after putting nitro in it

it weighs in at around 5-7kg and is made from all STEEL. its 290mm long by 81mm wide and is a dual chamber pipe.

original plan:


and finally, here it is:







and also 2 vids:
this is a test run: http://www.youtube.com/watch?v=DzCA-xTlh1s
and this is after the damage occured : :weird:http://www.youtube.com/watch?v=qqHkP3QECR8

what do you think? all feedback welcome. also if you listen in the first vid near the end where is slowly rev it up it sounds like a Harley at a certain point, excellent, hehe

its still got a LONG way to go as we only got 3 lessons a week there aint much time to work on it which sucks and its already term 3. plus my mate screwed up the alum hub on the lathe by cutting out too much metal so now the bearing for the hub doesnt fit :cry:

so does anyone here do dune buggy racing of the sort or know anything about it?

thanks for looking!

NOTE: i aint in the pics or vids as i took the pics and vids using my fone. also the kid in the first pic is not stoned even though he looks like it, lol

saleens7

sounds quiet (probably just the volume on the vid though)....cant wait to see how it ends up working...

is that you in the 3rd pic?...you look freakin creepy....

what engine you got in there?

my grandpa and me built a go-cart from an old frame he found and a 6 horse log-spliter motor....its pretty quick, but too small for me now....never got to get it to go top speed since the tire would always spin out when i punched the gas....but damn did this thing have some quick accelleration to it...the thing had no shocks though so it was a bumpy ride...and one time when we were testing out the engine the exhaust got so hot it turned yellow/gold and when it cooled down it started to flake....besides that, we also added a roll cage to it.....im pretty sure its too small for me now....that last time i drove it (2 years ago) i could hardly fit in it....too bad its up in michigan and im down here in FL...

ttoks

that is a honda 4 stroke no? if so if your looking for performance being a 4 stroke you want as little back pressure as possible, so although your exhaust looks nice, and i must admit sounds sweet, it probably wont help performance, other then that you may wanna put a really soft seat on that thing coz without suspension it's gonna be a bumpy ride, looks like she coming along nicely, a bit rough around the edges, but the edges are just for looks.

MadDogRC

thanks guys.

saleens7, PLEASE READ the WHOLE post, hehe. read the last sentence....

ttoks, it aint a 4 stroke. its a 2 stroke and i confirmed that.

there is still plenty of work to be done on the car, thats for sure and stuff having a soft seat, i love a bumpy ride! hehe. though i wish the car was a lil higher so it didnt bottom out though which sucks. oh well, the alum hubs for it will be finished shortly so we will have front wheels! all we need now is for our teacher to find spare chain links since we killed it.

trust me, the performance is amazing. i mean seriously, snapped the chain in half at HALF THROTTLE! thats sum serious power :-) hehe.

MadDogRC

either way, i'm getting a A+++ for this project as i had no help from the teacher or anyone else, hehe.

well, someone did try and help, and ended up screwing up a part that i had to fix..............noob, lol

for my first exhaust, I LOVE IT!

-Inverted-

Actually not once did you state the words 2 stroke, motor, or engine in your original post.....

I would bet the chain failure on user error and set up before guarenteeing that kind of performance from that engine. Seriously a 450cc quad isn't out snapping chains and they are much more powerful then the motor your using.

I compliment you on the progress but the name is a bit off. With no suspension and such low ground clearence it won't make much of a "dune racer". More of a go kart in my opinion.

SpeedAddict

He wasn't talking about the engine when he said to read the last sentance. saleens7 asked if he was in the third pic, but the last sentance of the first post already said he wasn't in any of the pics, he took them.

jatoracing33

thats wat inverted was talkin bout.

back on topic...looks nice, but you need a suspension of some sort.'
good luck

-Inverted-

I know... He told ttoks he confirmed it was a two stroke when in fact no such words were in the original post.

MadDogRC

i confirmed it as in i went to skool, asked the teacher for the manual for the engine and it says its a two stroke.

i didnt say that i confirmed it in my first post that it was a 2 stroke

considering this is all made from SCRAP metal its a good job. i spent $0 on the pipe and built it dead from scratch.

yes, i know we need suspension but we'd have to make it or find some super cheap as we have a tiny budget.


please, back on topic...

Mr. Mugen

The university I went to has a program that makes similar buggies. They won 1st place in a national comp. this year with it and my pal James was the head of operations. He had quite a few gray hairs sprout during the process. They used a 5hp engine and it had suspension. I will try to find a pic for you's.

Yours looks good so far. Just make sure your having fun! That is the important thing....oh yeah and learning something along the way.

Inverted.....why do you pick apart peoples posts? I see you do it all the time.....not bashing you man but come on. Your too technical sometimes. Stay kool.

MadDogRC

also its surprising i broke the chain since it is not a normal bike chain, its actually a half inch wide chain which is like some small industrial chain which is supposed to take the torque and power, but it didnt.

it didnt break with the original pipe on it, lol!

2916jr

I doubt it is a 2 stroke look at the valve cover on the engine it is a over head valve motor and the way the motor sounds it is a 4stroke

MadDogRC

2916jr, nup, its a 2 stroke. it clearly says it is in the manual for the engine and i also found the same engine advertised on the net as 2 stroke.

also the pipe is a dual chamber pipe so it really has changed how it normally sounds.

Mr. Mugen

So what ratio do you mix your fuel at?

PS you dont mix fuel on a 4 stroke.....that is what you's have there.

Mr. Mugen

oh yeah and if it was 2 stroke you would have an expansion chamber on it and you don't. Don't take offense to this. Your manual is wrong if it says it is a 2 stroke. Sorry. I have 6 of each and they are very different.

2916jr

take this off and you will see rocker arms a 2 stroke would not have that

MadDogRC

i dont get it then. my suzuki lt80 is a 2 stroke, doesnt need fuel mixing though as its got oil injection into the carb and also it doesnt have an expansion chamber. and the manual also says its a 2 stroke.

lol, why is everything lying these days!

MadDogRC

ah well, its a 4 stroke then. good to see that there a folk out there to prove me wrong and save me from getting into trouble.

it might hinder performance a bit, but we dont know that for sure as we dont have a dyno, obviously. there is a bit of back pressure and i designed it that way but as far as i know performance HAS increased and power is BETTER than the last crappy old pipe.

i will prove this by doing a speed run with my GPS. if it can climb the hill with the new pipe which we couldnt climb before, then its a fact that it has got more power.

Mr. Mugen

Hey man, I wasn't trying to call you out by any means. Your teacher should have taught you's a little better than that. Speaking of teachers.....what kind of teacher lets guys use the lathe with neck ties on? Heck we weren't allowed to have baggy sleeves let alone ties. I know they are tucked in but hey ....weirder things have happened.

hands without shadows

You dont even need to take of the cover, all you have to do is read the three letters on it. OHV.........Overhead Valve.

ttoks

yeah i thought so, it's a honda stationary engine, i bet it's either the 6 or 8 horsepower model, they are a good reliable little engine them, so the next chain doesn't break, make sure the pinion sprocket and the larger sprocket line up perfectly, i'll bet thats why the chain snapped, so far so good though.

and take your ties off before using a lathe, or any machines or power tools for that matter, and roll your sleeves up, they gets tangled in a lathe and it will do a lot of damage, they're not to be played with

MadDogRC

we all wear aprons using lathes and other tools and the ties are always inside the apron so they dont fall out. we never have to roll up our shirts as they arent loose and wouldnt get caught easily.

the only accident that happens is when idiots leave the chuck key in the lathe then turn it on. in the 30 years of the skool being open, never had an accident.

MadDogRC

i always thought it was a 4 stroke but it was the same as my motorbike engine setup since you didnt have to mix fuel even though its a 2 stroke which is really handy. it does sound different to a 2 stroke as it doesnt have that 'putt putt' sound but i thought that was the pipe changing it since the last pipe went ' putt putt BACKFIRE putt BACKFIRE putt put put putt BACKFIRE' lol.

also the fact i've never used a 4 stroke engine before deffo contributes to my lack of knowledge about it and thus being incorrect.

oh well, just wait for the test results to come in.

Mr. Mugen

I hope things go good for you's. Try and try again if it doesn't. Check your alignment between you 2 sprockets to make sure there is no side tension on the chain. You may also want to install some chain guides to keep it from slapping from side to side causing unwanted binding.