400EX Drag Quad

[brandan_k]

I am looking to build a relatively low budget drag quad that is still reliable enough to ride the trails with. I am wondering if anyone could help me with ideas. I am not wanting to really mess with the front end besides new bearings and bushings and maybe some 450R shocks. I am wanting to go wide on the rear. I am not wanting to do too much to the motor because I want it to remain reliable. If anyone has any ideas or has built one before that would be appreciated.

Please post all suggestions on this board or email them to me at nodnarbllerk@hotmail.com

Maybe a budget of around 6000 quad and all. I am trying to find a real cheap used 400EX in the area too.

[CHEVYZ]

450r shocks suck for drag racing (especially). They raise up the front end and make it launch like crap. What kind of drag racing are you looking into. As in what will your competition (main) be?

[BigFish]

If I had 6k, I sure as hell wouldn't spend it on a 400:macho

[bayou boy]

not doing much to the motor the only dragging you are going to be doing is dragging ***. this past weekend they had a couple of ex's on alky that were rolling but like the guy above said if you are going to spend 6g you should start with something better...you can get an 04' 05' 450 pretty cheap and spend the extra change on it.

[flauge]

I wouldnt even try to drag mine down at the local 1/8 mile, id prolly be the slowest. Everybody's got either banshees or raps.
Im with everybody else, if you have 6 grand and wanted to drag, id get something else if i were you. I myself would try to find a banshee for cheap and put the rest of the money in the motor.:ermm:

[bansheemorphine]

the guy wants a reliable quad so i wouldn't buy a banshee it would blow up real quick. with 6k you shouldn't waste it on a 400ex if u want to drag race find a cheap raptor or a 450

[flauge]

Oh ya, i forgot about the reliable part. A rap or a 450 would probably be the best then.......

[fastex06]

or ltz400 stage 2 cams, pipe, 14,36 , jetting, close to 83 mph

[H_W]

A 400ex is not a good drag quad, especially if you do not want to do much to the motor. It is only putting out about 26 hp stock. You definately should look at getting a raptor or a 450.

[400eXr1d3rZ]

A YFZ or Raptor 700 would be a good drag quad.

[XR650]

a 650ex makes a good drag/duner, and less than 6k

[firefighterjosh]

Personally if you have 6k I would get a YFZ or 450r used put a HRC kit or pipe and cam of your choice. It would be a great machine and prally be faster then your cheap 400 with some engine work. Even if you dumped 4k into a 400 engine it may be faster then a 450 with a pipe but not by much at all. Plus the 450 would be more reliable

[CHEVYZ]

Yeah, a different bike completely would be much more suitable for that choice. The 400EXs can be made to run, but it is not as simple as a few things to the engine. If you are looking to have a pretty fast bike with a mostly stock engine, you are gonna need something along the lines of a 450 or a Raptor 700.

[brandan_k]

Thank you for all the responses and so quick. Where I ride there are alot of smaller bikes (because of the gearing in the mountains and whatnot). This will be my first sport bike and I don't really want that quick of a bike. I am going to be running in the beginner class only and then head to the trails with the same quad. I will be racing in the same CC class so that is why I wanted to start small. I am willing to do some minor things to the motor (like a cam, jets, pipe, better carb) but the budget is looking more along the lines of 5000 (which includes bike, parts, tires, riding gear, and all mods). I don't think I can handle a 450 class or 700 class bike right now (I'm only 16 and have only ridden utilities). Thanks for all the helo and I would like to get information on turning a 400ex into a "drag" quad instead of buying a different model. Keep in mind that there are only about 4 drag races a year around where I live, so it isn't going to be a bike for solely drag racing.

Thanks again for all the replies (I also have a limit with the parents as to how big a bike I can get, and that limit is 400cc's).

[brandan_k]

I would be dragging on hardpacked ground in the beginner competition. It would be against people with the CC level from 301-450 cc's. I am willing to do a bore kit but I don't really want to do that much to the motor (pipe, filter, jets, cam, and ignition) if I had to get work done I would probably send it off to someone else to do it. What are some basic (mechanically speaking) mods that I should do. I am not going to mess with the front end or frame (except for gussets and skid plates) and I am planning on going 4 to 6 inches wider on the rear axle (with 2' wheel spacers and 4' wider axle) and lowering the front with 2' lowering brackets only while racing. For tires I am not sure if I should go smaller or larger as to diameter. Also, what exhaust gets the best power out of this engine (would I need an aftermarket header) that is not the top of the line but mid range price? I am thinking a 4 or 6' longer swingarm. What kind of gearing should I do. Also, is putting a 450R carb on it a good idea? What I am basically trying to find out is how to get the most out of this engine without increasing the bore and keeping it as reliable as possible. Thank you for your help.

[coryatver]

I don't know anything about this bike but I know it is FAST it won the open class beating all the Raptors and banshees so I know you can make 400s great drag quads.

[Wheelie]

Pump or race gas? How long is the drag?

A few thoughts: run 20" or 18" tires--less weight.

The stock headpipe is fine--even with a mildly modded engine.

[togup]

you said you wanted to go wide you can buy a +3 axle from rocky mountain atv for a measly 199.00. I got one and i've had it for a year and a half , I like it.

hope that helps.

[brandan_k]

I would probably be running on race gas. Around 110 octane. Looking into it I should be able to afford a bbk. I am wondering what size to go to and which brand is the most reliable also which compression is more reliable. The kit can be at most 450 cc's though, that is the limit on the class I am going to be entering.

I will look into that axle, thanks.

[lpmaster]

a 440 with hd studs, at 11:1 or 11.5:1 is very reliable, and get a stage 2 cam with it, you probably wouldnt need straight 110 octane with anything under 12:1

[oldskoolex400]

still think you should get a 450 since your not the most experienced rider you will eventually get used to it

[PismoLocal]

Originally posted by brandan_k
I would probably be running on race gas. Around 110 octane. Looking into it I should be able to afford a bbk. I am wondering what size to go to and which brand is the most reliable also which compression is more reliable. The kit can be at most 450 cc's though, that is the limit on the class I am going to be entering.

I will look into that axle, thanks.
Reliable and drag quad are two things that do not work together. If you truely want to be able to keep up with other drag quads your going to need a lot of work and your quad will not be very reliable.

If I was building a drag quad out of a 400ex on a limited budget I would build a 416 with a 12.5:1 or higher compression ratio with a stage 2 hotcam to keep it simple and cheap. I would get some HD headstuds and a crf timing chain. Then I would send the head for porting and polishing a long with some oversized valves. I would also get an FCR carb from ebay. Throw on a K&N filter and a slip on of your choice. Oh and don't forget about your clutch, buy a new clutch kit to go with your motor work.

[brandan_k]

Maybe I should change the title of this project. It is going to be a fourwheeler that I will be riding on the trails most of the time. Then about four or five times a year I will be competing in local drag competitions. I do not think the people I will be racing against will have top of the line equipment or will be racing quads solely built for drag racing. I am trying to build a reliable quad that when it needs to can pick up and go. I want to go longer and wider just for the looks (the trails I will be riding are pretty wide, or they are country roads).

Here's what I am thinking:

Frame- gussetted and cleaned

Suspension- new rear shock, lowering and widening kit in front, +4 swingarm, +4 (total) rear axle

Drivetrain- new chain, lower gearing

Clutch- clutch kit with new basket

Brakes- braded lines and wave style rotors

Tires- Razr2's in rear and Razrs in the front

Wheels- reinforced rear (Baja T-9's ?), aluminum fronts

Motor- 416 or 440 bore kit, HCR XR 400 cam, HMF pipe and powerbomb header, port and polish, 110 octane race fuel, oversized valves, HD headstuds, heavy duty timing chain, ProFlow K&N kit, DynaTek? ignition and rev box (I think it is programmable), oversized oil tank, new oil filter, TRX450R carb

What else should I do? I am not really worried about the cosmetics of it, since it is just a father son project. I will probably get one of those plastic renewer kits to clean it up a little.

[PismoLocal]

What compression ratio are you planning on running and are you planning on running a race gas strait or a 50/50 mix?

[BigFish]

U won't be doing much tight trail riding w/ a +4 swingarm. If u are planning on running dirt drags, +4 prolly won't do anything but spin. +1.25" swingarm will hook u up. We do alot of 300ft dirt drag racing (but the quads are set up for mx)

[HondaEXrider22]

You have the money, and want a 400ex with a 440 kit when you could just go for the 450:huh :huh

[brandan_k]

I regretably inform the members that have helped me so far with this project that it will not happen. My father has told me that I will not be getting a sport quad because of the speed and that he doesn't think I will be safe on it. This sucks but I am very grateful for all the replies that this thread got and the pm's and emails which I recieved.

Thanks again everyone.

[Xater]

thats too bad sport quads are way funner than utes.

[firefighterjosh]

What kinda UTE? Get yerself a Kawie 700, KQ 700, CAn Am 800, or somethign alongs those line. You will not be disapointed with speed.

[exrider272]

thats what im going to run next year is a 460ex but im going to do every thing possable to it this year i was running a raptor 700r and i worked good i was running high 7's down the track

[brandan_k]

Probably a Honda Foreman 450 or along those lines. I can't afford to spend 10,000 to get a Bomb or anything like that. I know that sports are way more fun, and I am very dissappointed to hear that I can't get one.