350x exhaust question.

[jsimonh]

I'm hopefully getting a supertrapp soon, and I'm gonna sell my current setup. Is the orginal headpipe a good performing pipe with the supertrapp or should I look for something else? I searched and have read tons, but couldn't ever find exactly what I was looking for.

[SWIGIN]

i always use after market headers due to the fact they are larger then the stock 350x and 400ex headers

[thebutelr]

I'm hopefully getting a supertrapp soon, and I'm gonna sell my current setup. Is the orginal headpipe a good performing pipe with the supertrapp or should I look for something else? I searched and have read tons, but couldn't ever find exactly what I was looking for.

I have read somewhere that the supertrapp is designed to only work with the stock header for the 350x. Someone chime in and correct me if I'm wrong.:confused:

[bigred1981]

My Supertrapp was mounted to the stock headpipe. I'm wondering the same thing as the stock headpipe is narrow and has quite a restricting bend in it.

[BigTBones]

I had a Bassini Header on my 350x with the super trapp. It seemed to do really well!

[NOS_350X]

Bassani and DG have the exact same bends, you cant tell the diffrence between the 2. About the stock headpipes, even larger aftermarkte ones dont flow as well as the stock ones. Theres a reason every dual exhaust for honda have the exact same bends, It just flows the best plain and simple. The only way our going to flow more than that stock headpipd can flow is if your going with bigger valves and over about a 450cc desplacement. With the welds grounded down on the stock 350x/400ex headpipes you cant beat them with aftermarket ones. its all a sales gimik save your money and keep the better stock headpipe.

[350xBomb]

I agree with NOS....stick with stock...honda got it right the first time, as usual

[SWIGIN]

no way guys....with head work and a high rev cam you really think it helpful to have the motor breathing out through 2 straws?

now it all depends what you are going for ...me i like top end and my motor is built for it as is the pipe

[brapp]

but with the 350x;s i noticed in alot of the older conversions into the 250x frames when u do bigger cama nd bigger valves and big bores to get more power u tend to lower reliability majorly, i have abotu 6 or7 motors that gernaded from troying to get too much power oout of them. and now thie rnot even good for alot of thie rparts. caus e3of the ones i have locked up the top ends and when it shockloade dth etrany it spun off shafts or shatterd gears or broek cases.

[NOS_350X]

no way guys....with head work and a high rev cam you really think it helpful to have the motor breathing out through 2 straws?

now it all depends what you are going for ...me i like top end and my motor is built for it as is the pipe


Ride my 350x, Its all topend. i have about 6 diffrent exhausts for the 350x's and jettin tells no lie, stock flows better. Its not about bigger tubes, bends makes the aftermaket ones flow so poorly, and the stock ones flow so much better, and its not about having smaller tube its about VELOCITY. Pull off that stupid aftermaket one put on a stock one and see youll have to go up on your jetting. I am assuming that you know to grind the welds down on the stock pipes. If you dont then yes your correct, aftermarket flows a BIT better but with the welds grounded down stock will flow better than and oversized headpipe.

[thebutelr]

Ride my 350x, Its all topend. i have about 6 diffrent exhausts for the 350x's and jettin tells no lie, stock flows better. Its not about bigger tubes, bends makes the aftermaket ones flow so poorly, and the stock ones flow so much better, and its not about having smaller tube its about VELOCITY. Pull off that stupid aftermaket one put on a stock one and see youll have to go up on your jetting. I am assuming that you know to grind the welds down on the stock pipes. If you dont then yes your correct, aftermarket flows a BIT better but with the welds grounded down stock will flow better than and oversized headpipe.

Where are the welds that need to be grinded down? :confused:

[jsimonh]

Ride my 350x, Its all topend. i have about 6 diffrent exhausts for the 350x's and jettin tells no lie, stock flows better. Its not about bigger tubes, bends makes the aftermaket ones flow so poorly, and the stock ones flow so much better, and its not about having smaller tube its about VELOCITY. Pull off that stupid aftermaket one put on a stock one and see youll have to go up on your jetting. I am assuming that you know to grind the welds down on the stock pipes. If you dont then yes your correct, aftermarket flows a BIT better but with the welds grounded down stock will flow better than and oversized headpipe.

Could you tell me more about grinding the welds down?

Edit: when I posted mine, I seen thebutelr had just posted the same thing.:D Great minds think alike.:beer

[NOS_350X]

Look into the headpipe right where it bolts to the head. There are 2 welds, (one on each tube) grind those down smooth and youll be cookin.


Read the 3rd post down.

http://www.exriders.com/vbb/showthread.php?s=&threadid=258416&highlight=400ex+headpipe

[jsimonh]

The stock one I'm bidding on ends in a couple of hours, so I'll either be getting that one or trying to locate one here. Sounds like the stock is the way I'll definatly be going. Thanks guys for all the input.

[thebutelr]

Could you tell me more about grinding the welds down?

Edit: when I posted mine, I seen thebutelr had just posted the same thing.:D Great minds think alike.:beer

Well said man :cool: . :beer

[NOS_350X]

Both exhaust's the stock 350x and 400ex exhaust have theses little welds that holds on the colars for the flange thing that actualy bolts onto the engine. If you take that stock exhaust and look down the 2 tubes that bolt to the engine youll see what i'm talking about. Just take a die grinder or something like that and grind them down smooth. Ill see if i can take a pic later tonight.

[kb200x]

Both exhaust's the stock 350x and 400ex exhaust have theses little welds that holds on the colars for the flange thing that actualy bolts onto the engine. If you take that stock exhaust and look down the 2 tubes that bolt to the engine youll see what i'm talking about. Just take a die grinder or something like that and grind them down smooth. Ill see if i can take a pic later tonight.


Is the 350x header and the 400ex header the same? Interchangable?

[HRC1]

If you go to supertrapp's website and download the instructions for the 350x pipe it tells you there is no gain to be had from a larger headpipe. BUT, that is on a stock bike as well. I have to dissagree and say that with a high comp and cammed motor that is ported such as mine is, a stock headpipe will be the cork in the system. Larger jets don't always mean more flow. There is a reason that almost all atv exhausts use larger headpipes. They flow better.

[SWIGIN]

i agree....bin there and done the grinded out stock header thing .....on a real built motor you need a larger header and pipe

[mudbogger]

The stock one I'm bidding on ends in a couple of hours, so I'll either be getting that one or trying to locate one here. Sounds like the stock is the way I'll definatly be going. Thanks guys for all the input.


I have 1 for you-it is rusted up pretty good-but it is surface only-PM me if you need it.:w00t:

Also, has anybody ever measured the ID of the stock versus the aftermarket by chance -thats a good indication as well-they look very similair in some cases.;)

[NOS_350X]

Is the 350x header and the 400ex header the same? Interchangable?


No, it takes some cutting and welding to get it in there.

And guys that are doing the 400ex headpipe i forgot to tell yall that you need a longer brake hose also. Going from the resivor to master. Sorry




If you go to supertrapp's website and download the instructions for the 350x pipe it tells you there is no gain to be had from a larger headpipe. BUT, that is on a stock bike as well. I have to dissagree and say that with a high comp and cammed motor that is ported such as mine is, a stock headpipe will be the cork in the system. Larger jets don't always mean more flow. There is a reason that almost all atv exhausts use larger headpipes. They flow better.

Ill stick to what the experts say, not your interpitation. High comp, cam and ported dosent even start the list of what my 350x has done.

[SWIGIN]

o.d of most after market headers are 1 1/16 - 1 1/8 with 1 1/2 pipe

[SWIGIN]

Ill stick to what the experts say, not your interpitation. High comp, cam and ported dosent even start the list of what my 350x has done.[/QUOTE]




experts???.....ever see a tc 350x pipe or even a tc 250x pipe?

if a old team honda rider dont know what he doing id like to know who the ''experts'' are

[NOS_350X]

just measured,

aftermakrt: 1.14in

stock at the welds: .89in

stock witht he welds grounded: 1.12 in

[NOS_350X]

experts???.....ever see a tc 350x pipe or even a tc 250x pipe?

if a old team honda rider dont know what he doing id like to know who the ''experts'' are


Lets see what the dyno tells. Rider, not mechanic. It really dosent matter what tc or any other company says there trying to sell a product. Look at a boost bottle on a banshee, they do absoutly nothing but yet every company sells one.

[SWIGIN]

your saying tc is not a mechanic?

hes bin building motors for what....like 20 years

[mudbogger]

Thanks for the measurements -I apprec it!!

[HRC1]

No, it takes some cutting and welding to get it in there.

And guys that are doing the 400ex headpipe i forgot to tell yall that you need a longer brake hose also. Going from the resivor to master. Sorry





Ill stick to what the experts say, not your interpitation. High comp, cam and ported dosent even start the list of what my 350x has done.


Ya know i try to be professional when i post here, but i've noticed you like to contradict me. For one, I'm not just talkin out my a** when i'm posting. Have you ever herd of John Ziehl? He ownes venom performance, Builds some of the fastest TRX450R's in the country And is the inventor of the pulse charger exhaust, wich is on my 350X, the black widow piston and numerouse other improvements for the atv world. He's a buddy of mine and the person i consulted when building my motor. He's been building atv/motorcycle motors for 20+ years, and the first think i was told is ditch the stock headpipe, it's too small for what i'm doing. Especially after he ported my head. The stock header is fine for retaining low end torque, but will be the bottleneck in the higher rpm's. There's a reason why all aftermarket systems have a larger header, his pulsecharger system included. The same reason i had to go to bigger headers on my car when i installed AFR heads and a new cam and intake. The stockers wont cut it. I don't know what aftermarket header you measured but mine is marginally larger than the stocker. And i've seen the diff between stock header VS aftermarket on his dyno, not on a 350x yet, but on a 450r. Like trying to blow through a drinking straw vs a firehose... I did ask the experts.

[NOS_350X]

And i've seen the diff between stock header VS aftermarket on his dyno, not on a 350x yet, but on a 450r.

Well i have to agree, ON A 450 a full system helps drasticaly. But where not dealing with a 450. Then engine designs are completly diffrent. Just pull off the head and compare the 2, Try to check the valve clearances. There is nothing the same about a 450 and 350x except there 4 stroke. Here we are dealing with a dual exhaust port head. I live 30 minutes from Esr and Sparks racing, Ludas racing B&B racing. All engine builders have there strog points, The thing to do is find who does what and mix and match to suit your style the best. Really the onlyway to check what headpipe is best would be to put them on a flow bench and run it through the head then the headpipe. In that case porting would most likely make a bigger affect than a headpipe. Like i said before it all depends on what your building and how it all fits together, i have herd neomours times from many builders that you cant beat that stock system, unless your running a huge displacement. Ive built my 350x to run and she runs good, and would love to see you guys that think you have fast x's compare to it. But dotn think well see them next to each other anytime soon.

[jsimonh]

I didn't realize this was such a heated debate!:eek:
I have a stock headpipe on the way along with a supertrapp tail pipe. Even with the stock headpipe, I'm guessing it will be alot better than my full DG setup. If not, I'll put the DG back on and resell the other, but I doubt that will happen.

[HRC1]

Well i have to agree, ON A 450 a full system helps drasticaly. But where not dealing with a 450. Then engine designs are completly diffrent. Just pull off the head and compare the 2, Try to check the valve clearances. There is nothing the same about a 450 and 350x except there 4 stroke. Here we are dealing with a dual exhaust port head. I live 30 minutes from Esr and Sparks racing, Ludas racing B&B racing. All engine builders have there strog points, The thing to do is find who does what and mix and match to suit your style the best. Really the onlyway to check what headpipe is best would be to put them on a flow bench and run it through the head then the headpipe. In that case porting would most likely make a bigger affect than a headpipe. Like i said before it all depends on what your building and how it all fits together, i have herd neomours times from many builders that you cant beat that stock system, unless your running a huge displacement. Ive built my 350x to run and she runs good, and would love to see you guys that think you have fast x's compare to it. But dotn think well see them next to each other anytime soon.


Far From a invite to dragrace. I built mine for fun in the dunes, and i really don't care how fast your bike is. If i really wanna go wicked fast anywhere i grab my 250r anyways... The 350x wasn't built to be a no holds barred world beater, just a fun project that was warmed up a bit, and john happened to be interested in the build for it, so i took his advice. As far as the 450r motor vs 350x motor, lol, i know verry well what lives under both those rocker covers. The valvetrain setup is completly different, But just because the valvetrain is different doesen't have any effect on the fact they are both 4 STROKES!. In that aspect they are identical. ( my drag car is a 4 stroke and it sure liked it when i put larger headers on) They both have 4 valves, the only difference in the flow path is the single exhaust port on the 450r. I have 3 350x's and different pipes on each one. the built one has a pulsecharger with a cobra headpipe,(all i could source, had it laying around) the 86 is stock except for the uni and the DG xcellerator full system, The reverse megaphone system, and an 85 that's bone stock. The dg is actually a really good design. Why is that? it incorporates a reverse megaphone front on the silencer that creates vaccum, as well as the discs on the silencer, coupled with a larger headpipe. I'm sure it's more suited to a built bike but it was on there when i got it, so no sense changin it. It's basically what a supertrapp would be if they offered a larger headpipe. Like i said, on a stock bike, your not gonna beat the supertrapp. And i plan on someday equipping the stock 85 with one. You can go to big on header size, i will admit that, killing throttle response and low end. But in the case of aftermarket headers for a 350x your not gonna find anything too big. It's not like were going from 1-1/8 inch to 2 inch headers here. As far as sparks and luda, i'm not listening to anything those guys say, they both were debunked long ago on a diff website. as for porting, if you have no way to get the exhaust gasses out of the head porting is worth nothing.
Anyway, i'm done arguing, you stated you can't beat the stock headpipe no matter what, now you say you can with large displacement, wich is what i said in the first place. I'm saying stock bike, stock cam, stock comp, run the stock header. You like torque? stock header, You like all top end? aftermarket header and some pipe with a reverse megaphone silencer with disc's. Built bike, biggie comp, bigger cam, bigger carb, stroker, whatever, i'm going up on header size.

Gotta roll, the UPS guy just dropped the new supertrapp off for my XR600, and Because i like torque, i'm keeping the stock header...

[badculture]

after wasting 10 min of my life reading this I have to ask..............why?

[NOS_350X]

Far From a invite to dragrace. I built mine for fun in the dunes, and i really don't care how fast your bike is. If i really wanna go wicked fast anywhere i grab my 250r anyways... The 350x wasn't built to be a no holds barred world beater, just a fun project that was warmed up a bit, and john happened to be interested in the build for it, so i took his advice. As far as the 450r motor vs 350x motor, lol, i know verry well what lives under both those rocker covers. The valvetrain setup is completly different, But just because the valvetrain is different doesen't have any effect on the fact they are both 4 STROKES!. In that aspect they are identical. ( my drag car is a 4 stroke and it sure liked it when i put larger headers on) They both have 4 valves, the only difference in the flow path is the single exhaust port on the 450r. I have 3 350x's and different pipes on each one. the built one has a pulsecharger with a cobra headpipe,(all i could source, had it laying around) the 86 is stock except for the uni and the DG xcellerator full system, The reverse megaphone system, and an 85 that's bone stock. The dg is actually a really good design. Why is that? it incorporates a reverse megaphone front on the silencer that creates vaccum, as well as the discs on the silencer, coupled with a larger headpipe. I'm sure it's more suited to a built bike but it was on there when i got it, so no sense changin it. It's basically what a supertrapp would be if they offered a larger headpipe. Like i said, on a stock bike, your not gonna beat the supertrapp. And i plan on someday equipping the stock 85 with one. You can go to big on header size, i will admit that, killing throttle response and low end. But in the case of aftermarket headers for a 350x your not gonna find anything too big. It's not like were going from 1-1/8 inch to 2 inch headers here. As far as sparks and luda, i'm not listening to anything those guys say, they both were debunked long ago on a diff website. as for porting, if you have no way to get the exhaust gasses out of the head porting is worth nothing.
Anyway, i'm done arguing, you stated you can't beat the stock headpipe no matter what, now you say you can with large displacement, wich is what i said in the first place. I'm saying stock bike, stock cam, stock comp, run the stock header. You like torque? stock header, You like all top end? aftermarket header and some pipe with a reverse megaphone silencer with disc's. Built bike, biggie comp, bigger cam, bigger carb, stroker, whatever, i'm going up on header size.

Gotta roll, the UPS guy just dropped the new supertrapp off for my XR600, and Because i like torque, i'm keeping the stock header...

AWWW i feel so special you wrote a novel just because of me:postwhore

Whats done to that 250r i like racing them also :Bounce There becomes a spot where you need that larger headpipe. But the flow and velocity of the stock one ON A 350x (not car, 450, or anything elce) is hard to match and i dont think there are too many engines out there that take a larger one. I will admit i do have a larger headpipe on one of my X's going into a supertrapp, with no dics. For whats done to the engines where dealing with i do not belive that a larger headpipe would help performance one bit.

Sparks and luda's??? wtf? Have you looked at the results of the FSW??? Sparks dominates.

We dissagree, who cares and lets move on.

[jsimonh]

We dissagree, who cares and lets move on.

I think that's an excellent idea!:beer