Pipe Advice

[kevmo]

Ok, time for my 2005 EX to start being non-stock....First step, exhaust.

Questions -

How much more of a gain am I going to get if I do head pipe and silecer or simply just go with a slip on?

Right now I am considering the HFM Sport series but am open to suggestion.

BTW - At the same time I plan on airbox vents and re-jetting.

[2004exrider]

If your not planning on boring the engine out, i'd just buy an hmf slip on. I got some pretty good power with mine and they sound great! Opening up the intake will help out a lot too, i'd suggest either a K&N or Uni.

Jimmy

[trx400exxracer]

I would get a yoshimura full comp series

[kevmo]

At this point I am not planning on boring out, but you never know?

The game plan right now is uni filter, airbox cover and exhaust.

I am not ahuge Yoshimura fan (just personal preference) and like I said am leaning HMF but considering White Bros and FMF as well.

Let me ask this....with the few basic mods I described will I notice any real diffrence between a slip on and a full system?

[trx400exxracer]

My 400 came with the slip on hmf but it had a stock air filter with no lid and a 165 or 170 main jet and when I put my uni air filter on I could notice it like a night and day difference
what I am saying is that to notice it you have to jet it get an air filter adn the pipe all at the same time to notice a difference and believe me you will notice it

but if you are going the get the hmf slip on I would get a fmf powerbomb header

I would also look around for a used 450r carburator and also a stock xr250 cdi box to help your performance

those are just some cheap mods that make a good noticable difference

I would also look into getting some aftermarket shocks or some 450r front shocks you can get them off of ebay for about $325

[trx400exxracer]

Originally posted by kevmo
At this point I am not planning on boring out, but you never know?

The game plan right now is uni filter, airbox cover and exhaust.

I am not ahuge Yoshimura fan (just personal preference) and like I said am leaning HMF but considering White Bros and FMF as well.

Let me ask this....with the few basic mods I described will I notice any real diffrence between a slip on and a full system?

that is a good choice I wouldn't bore it out until it actually needs it unless you just feel the need for speed or you like to build quads

[cals400ex]

get a full system. thats my opinion. i have used a variety and the new full HMF does well. i would recommend it

[400exrider707]

Originally posted by trx400exxracer
My 400 came with the slip on hmf but it had a stock air filter with no lid and a 165 or 170 main jet and when I put my uni air filter on I could notice it like a night and day difference
what I am saying is that to notice it you have to jet it get an air filter adn the pipe all at the same time to notice a difference and believe me you will notice it

but if you are going the get the hmf slip on I would get a fmf powerbomb header

I would also look around for a used 450r carburator and also a stock xr250 cdi box to help your performance

those are just some cheap mods that make a good noticable difference

I would also look into getting some aftermarket shocks or some 450r front shocks you can get them off of ebay for about $325


XR 250 cdi is a bad idea!

[trx400exxracer]

Originally posted by 400exrider707
XR 250 cdi is a bad idea!

why

www.powroll.com it is on this web site on the 400ex section

[underpowered]

Originally posted by trx400exxracer
why

www.powroll.com it is on this web site on the 400ex section

because it will be hard to start. get a CDI made for the 400, not a cheap alternative such as the XR250 box. GT Thunder makes two boxes fro the 400. TC also has one made for the 400. WHite bros, Big Gun, And other cheap boxes are just the xr250 boxes.

for a 400ex u will only see 2 hp gain for slip on
for the full system u will only see about 4-6 more hp.
u will rev alot faster than the stock muffler.
that hp reading is for a stock engine. on a modified engine u would see more gain.

[400ex28]

HMF/UNI:blah:

[hardkoratvmxr]

get a curtis sparks full system and either an uni or k&n air filter

[400exstud]

for a 400ex u will only see 2 hp gain for slip on for the full system u will only see about 4-6 more hp.u will rev alot faster than the stock muffler. that hp reading is for a stock engine. on a modified engine u would see more gain.

Lets be serious here. With a slip on you will get like 1 hp on top end. With a full system you will get like 2 hp on top end. All of the gains will be in the low to mid range.

PS: Check the dyno section about the 416 ex making 33hp. A stock 400ex makes about 27 hp. If you would get 6 hp from a full system you would have the same power that that 416. I don't think so.:p

lowend is more important than top end

[ride red 14]

if i were you and wanted to make my ex sound really good id do what i did and put on a full lrd exuast and it sounds great

[GOTFEAR]

I replaced my tc pipe two a LRD makes good power . 440 hot cam big valves masive porting and std carb. cant get off the corners with the 450's but soon off it will run with them.