Duncan racing pipe?

[wild400ex]

I just recently purchased a 400ex that has a White Brothers E Series pipe. I rode a totally stock 400 the other day and really didn't notice a difference, and in a 200 yard drag race, my bike was only about 2 bike lengths ahead of the stock 400.

I was reading about the Duncan raccing Fatboy 4 exhaust. It's a 20% power increase and a 20 bike length gain in a 300yard drag.

My question is...Is it worth selling my E series and buying the Duncan Fatboy 4. I figure the Fatboy 4 is more focused on real power and racing. I'm power hungry, and want nothing but the best for my 400. Also what is said to be the most powerful pipe for the 400ex?

[Alex654]

I have heard the Duncan pipe is good but I think Curtis Sparks are about the best. But I dont have either so I dont know for sure.

[TC426EX]

There are tons of posts about this but basically if you want the best pipe get the SPARKS X-6, TC, or LRD. The Duncan is supposed to be in the same ballpark, but I couldnt tell you because I never rode one. I HAVE owned both a TC and now a Sparks, and I can tell you that the TC has better torque through the rpm range (you cut 5" off the stock header to run it, but it is LOUD), and the Sparks is better on top end and built motors. The sparks is only available as a full pipe. The X-6 or the X-4. The X-4 is more for mid- bottom and a stock motor, and the X-6 is for built ones but still does good on stock. The LRD is probably one of the other top 3 full systems people rave about but then again you cant forget CT. There are alot of good pipes for the 400. I would say DUncan, TC, Sparks, or LRD are your best bets. Any one of them would be better than the E series, I used to run an R4 and they are similar so I know....

[s-10s_rule]

CT pipes are the winners of almost all dyno shootouts, and the E series is actually a very close second. Try adding some more disks to the E-series you have, there is no way at all that any pipe will make a 400ex 20 bikes ahead of another with any other pipe. Stock pipes are not all that bad on Hondas, Dunacn is full of crap 100%, I wouldn't buy their pipe simply because that is such a lie, I now have less respect for them thanks to the info you have given me.:grr: I was not aware of that rediculious claim.

[toby400ex]

HAHAHA, 20 bike lengths, thats some funny chit.:blah:

[Giz400ex]

Originally posted by TC426EX
. There are alot of good pipes for the 400. I would say DUncan, TC, Sparks, or LRD are your best bets. .... :D :D

[wild400ex]

Yea, thanks for all your thoughts. I'm gonna have to re-read that. I think it means 20 bike lengths ahead of a stock pipe. The only problem with the Duncan pipe, is that it's expensive.

[Puff Daddy]

MY BEST BET OF CHOICE:

1. Sparks X6
2. CT sonic
3. TC
4. Duncan
5. LRD
6. HMF
7. Yoshimura
8. WB
9. Pro Circuit
10. Big Gun
11. Hetrick


DG, FMF, supertrapp, & cobra are off the scale.........
(no offense Tim Farr)

[thame2010]

Originally posted by Puff Daddy
DG, FMF, supertrapp, & cobra are off the scale.........
(no offense Tim Farr)

Man, if Tim could be running a good pipe, he may even won :(
DAMN DG PIPES :mad: