delima

[yellow machine]

I have a bit of a delima, I can not decide what to buy.

I have a stock 400 and about 500 dollars to spend, I have heard people talk about cams, pistons, filters, pipes ect. I have fallen in love with the DMC alien system, but I am not sure if this is the best move. If i got the exhaust and filter kit I have killed the 500. is it worth it to get the exhaust now and wait on engine mods, or do the engine mods and wait on the exhaust. I am not interested in a 440 kit but a 416 would not be all bad.

help me, i am confused(with +or- 500 dollars):D

[Texan32]

I just got my Alien put on. AWSOME. I haven't riden any other quads with different pipes yet, but i will assure you, the DMC makes a difference. I went riding yesterday and now i realize that with all the newfound power, i have to go with a higher gear ratio. There is that much power to spare.

I think you would be better off going with a pipe and jet kit first. That way when you do get more money (for the cam/416 stuff) you already have a well vented intake and exhaust. You can dump all the fuel you want into your combustion chamber, but if you don't have an open enough exhaust, it wold be worth a hill of beans.

Just my opinion. I personally would go DMC. its a little loud, but not annoying. And the power increase....OMG.

[400exRacerX]

I'd wait for the motor mods after you helped your chassis out first. With that 500 bucks i would get myself some shocks or tires. My quad only has the basic motor mods but yet is worth over 11k. The chassis is a very important place to mod, but yet very expensive.

[Tommy 17]

i did cam and piston porting and carb mod first... if u don't get the porting or the mod carb it will be 500$... i beat piped 400ex all day... right now i am goin for handling so the pipes gonna be on hold till atleast august or so... but i would do a cam and piston b4 i would go pipe.... thats just me....

[400MXer]

well, if you get a pipe now, then you'll be free flowing for when you get your motor work done. But, if you get the piston and a cam, then you'll have a "sleeper" on your hands...people will think you are stock, then their jaws will drop when you leave them in the dust, this happened to me once at the dunes. I thought i was gonna kill this guy on a 400 with a stock pipe in a drag race. well he killed me. I pulled up next to him afterwards and he told me that he was stroked, bored, ported, carb, ect.....but had a stock exhaust.

[DESDAK4]

As you can see with all these posts there is not any clear cut way to go. I will tell you I have my 400 with just an e-series slip on and some tuning along with a modded head pipe and it just depends on the day and who had the shift when it comes to racing my friend who has done all the same things except he has the full DMC system. You can take that for what it is worth to you.

[tprender]

The stock head pipe on a 400 is very good. Take it off and clean up the inside welds on the two pipe and it will flow much better. If you measure3 the size of the pipes compared to some of the aftermarket ones the stock is the same size and the bends are very close. For thew money just rejet your carb and it will run very good. The gains by other carb are not that great for the money that they cost, unless money is no object.
This is the mods that will work and don't cost very much.
1. Clean up the head pipe welds.
2. Get a WB E series slip-on. In tests it is 2nd best to the sparks full system.
3. Stock carb rejetted.
4. Foam filter with Outerwares cover.
5. Steering Stabilizer
6. Mod the airbox some way to get more air.
7. Get some different tires after the stock ones get holes in them.
Don't believe everything that you read in the mags. Alot of things just look good, but don't make you go any faster or much faster for the money. These are some things to do before you start working on the engine size.

[Kadafiy]

tprender, Will I need to rejet if I grind the welds out of the head pipe?

[DESDAK4]

I don't think you would have to rejet or not I did mine at the same time as I did all my other work and as you can see I had to rejet. But anyway, working with the jetting on a stock 400 isn't a bad idea.

[Blackguywithouta400]

If you want to be the next Rico jumping your quad all day then i would go with shocks first. I have the DMC and got mine when i i just had a stock motor. I was running a K&N and open air box the thing just rocked, i tuned my carb myself and there were many 400's with different exhaust i was able to beat. I would kill the WB bikes all day from bottom to top. I would take the money and get the pipe. Then work your way up. Your going to need it in the end. Then you can just work your motor how you want it, you can then add xr400 cam 130$ and so on. I think anyone with a slip on that beats a bike with a full system means the full system needs a lot of tuning.:p

[DESDAK4]

I have just the slip-on and my headpipe has been ground out the DMC full system I run against is very well tuned as is mine and we are neck and neck reguardless.

[yellow machine]

:) Thanks for the reponses everyone!

With the help of all of you I am going to get the DMC and filter kit, the way I look at it is I was going to get it someday anyway (it is different looking than everyone elses, and not many people out here are using it yet, and someone once said "different is good") and there is no time like the present. So it looks like the cam, ect. will have to wait.

Anyone out there who has put the DMC on have any good tips for insatllation? Air box modifications that worked? Jetting combos that worked? I am down here in Nebraska, so my elevation is not so high.

Any input would be helpful!:)

[Blackguywithouta400]

160 Main jet open airbox with a K&N filter with an outerwears cover. 42 pilot and then move the needle clip down 1 notch to the sharp tip of the needle. This is not for a Jet Kit there jets are differnt this should only cost you 10$ to jet 5 for the main jet and 5 for the pilot jet u dont need to buy a jet kit.

[DESDAK4]

My friend and I live here in ND less than 1200ft.. The instalation of his DMC was pretty simple and straight forward but after a day of riding we figured out we had to drop the main jet one step lower to the 165. We also cut the entire center out of the lid on the airbox and used it to hold the outwears lid inplace which works great.

[Texan32]

with no prior experience with taking the 400 apart, i did the pipe and jet kit in about 2 hours. I took a while talking to rocky mountain. I thought the jet kit came with a new pilot...it doesn't. The K&N kit just tells you to readjust the mixture screw. I followed the instructions verbatum. Runs like a raped ape. I went ahead ad used the K&N needle, clip, and washer and put clip in 3rd notch (per K&Ns instruction). Alot of people like the 42 pilot jet. I don't really mind using my choke. It lets me know that the engine is warm enough. More than likely you are going to have to slightly bend you exhaust flange studs. The one on the left port (left if your sitting on it) is is kinked out a little. Loosen the nut out and tap on it with a hammer. Hit the nut, not the stud...you'll bugger up the threads otherwise.

Also, you may think the stock pipe doesn't want to come out. It will. Just push the tail end of the pipe up and it'll pop right out.

Hope it all works out for ya. Let me know how yours goes. I don't know who/where your are getting you system, but JR at Factory Racing is who i talked to (1-800-265-2563). I have ordered from there a couple of times. GOOD PEOPLE! It ran me $489 to my door and took 4 days.

James