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smokin01'400
07-28-2001, 07:56 PM
i need some help on making my 400 go faster and have more life to it. i was thinking a WB rev kit, but i talked to my g/f's cousin who used to be an ATV mechanic and he said his friend got an "unlimited'' CDI box for his 400 straight from HONDA. he told me to get that. so i called my dealer and asked and he said they make no such thing and he said that doesnt even sound like honda. any help? i dont want to waste money on a WB kit if it only adds 1,000 more RPMS. please help:confused:

07-28-2001, 09:01 PM
huh how is it a waste of money it is a good deal i have dragged a stock 400 vs a stock 400 with a wb rev box and it beat it on top sure it tied it every where else but passed at the end

kabd69667
07-29-2001, 07:57 AM
I'm not sure on this but i think that's the highest rpm's that you can get in a CDI. curtis sparks-1000 wb-1000. well, those are the only ones i've seen. unless your racing, i would advise against a CDI

smokin01'400
07-29-2001, 09:22 AM
thanks for your help guys, now i think i will get the WB. will it hurt anything in the engine if it's stock? i am planning on jetting it and putting a pipe on it and maybe a sparks andvanced flywheel key but someone told me that they dont recommend them for stock motors? thanks for the advice

smokin01'400
07-30-2001, 09:52 AM
how much faster will i go top end? i am also planning on some minor mods like a pipe and k&n jet kit. will that help? will it hurt my piston or anything internal? i hear they arent recommended for stock motors? please help. later:rolleyes:

nakomis0
07-30-2001, 10:16 AM
I wouldn't recommend it for a stock motor either. theres just not enought power on a stock. I wouldn't think it would help your top end very much. And as far as hurting things internaly, of course theres more wear when you piston is revving faster. I have a few engine mods and the WB rev limiter, and I occasionally hit the rev limit. I think its still at a safe limit, I would never keep it redlined intentionally. An unlimited rev sounds pretty unsafe.

smokin01'400
07-30-2001, 10:24 AM
thanks man, maybe i will mod it out first. i jsut want to be ahead of me freinds on their stock 400's. any onther cheap mod to make me smoke em in a race? later

nakomis0
07-30-2001, 10:27 AM
14 tooth:macho

smokin01'400
07-30-2001, 10:32 AM
wont that slow me down top end? i am plenty happy with the low end mine is putting out stock, it's in the shop now getting service and tuned up so it will be better when i get it back, cuase it wasnt running right and i was still wooping on everyone. a 16 tooth would slow my acceleration right?

nakomis0
07-30-2001, 10:41 AM
Ya 16 would slow down accel a bit, and a 14 would slow down your top speed. I guess it depends on your riding type. Around the trails we never got to the top speed of the 15 tooth that much and for the sand 5th gear couldn't pull very well. Thats why I liked the 14 tooth so much. But ya as far as riding on open roads or something where top speed was a concern, I didnt like my 14 tooth. But I loved it for everything else.

smokin01'400
07-30-2001, 11:07 AM
i would set my quad up for low end torque anyday over top end. i would get the 14 tooth but then my freinds would say they kill me and stuff but mine will be geared lower, they are too stupid to realize that. i ride roads around here alot and that's why i am getting bandit tires because they last a long time. but anyways, i am done with top speed because i had an accident. i was pinned doing about 70 up this hill and a dog came out of nowhere and i hit it broad side, my brandnew 400 flipped over on the pavemnt 4 or 5 times and so did i, i bent the tie rod and the handle bars and the back of the sub-frame. nothing major, but i need a new sub frame. so i am done flying on the roads, it only makes people mad and it gets boring. so i will work on low end now. so i can whoop on everyone in the local riding spot called the pit. it's like riding at the coal piles but dirt. loose river bottom dirt. so i will whoop on them. any mroe advice? let me know. later

07-30-2001, 12:29 PM
Make sure your throttle cable is adjusted correctly,,,they normally ship from the factory with alot of slack...:devil

smokin01'400
07-30-2001, 01:35 PM
thanks for the tip on the throttle cable, i will call the dealer now and tell them to fix it while it's down there. later
:cool:

xcntry
07-30-2001, 03:02 PM
I would not advise a rev limiter at all . I like the way that duncan racing looks at it. They build there engines to run within the specs of the engine. They have built world championship winning 440 ex's with tons of mods utilizing the stock rev box. So in my opinion if you want to keep reliability up leave the stock cdi in. Work on gaining your HP in the midrange. Your engine and pocketbook will thank you for it.:D

smokin01'400
07-30-2001, 08:08 PM
thanks for the help, i will consider every angle of this topic! since there are pros and cons. later:cool:

DISHO1
07-30-2001, 08:49 PM
the xr250 cdi box is the same thing white brothers sells as there own. they just mark up the price!! the only thing about most of the rev kits is they have trouble starting in the winter. most of the high rev cdi box needs to spin about 100 to 110 rpms to even produce a spark. the stock 400ex cdi box needs around 70 rpms to produce a spark.

in the winter the starter on a 400 sometimes can not spin the motor 100 or 110 rpms to get the high rev cdi to produce a spark.

on a kick start bike you can spin the motor faster than electric start when starting it.

smokin01'400
07-30-2001, 08:55 PM
DISH- thanks for the tip. my dealer adjusted me fuel/air screw for this past winter, and will do it again this winter to help ease the starting, maybe it will help. where is the cheapest place to get an XR250 cdi? thanks. later:cool:

DISHO1
07-30-2001, 09:02 PM
http://www.servicehonda.com/

smokin01'400
07-30-2001, 09:05 PM
thanks, i am an idiot, i go on this site all the time. will it fit right on? no adjustment? later

07-30-2001, 10:47 PM
Hey smokin01'400
I have had the 99' XR250 box on my bike since it was a stocker. To be honest with you I did'nt notice it too much at low rpm, but it screamed up top! Without any problems. The 250 CDI lets the motor go to 10,200 rpm. A stock Honda XR400 will go that high with no problem. I know because I have one. Like one post the only draw back is the cold starting when it is cold. I carry both CDI boxes at all times, if it is cold I will use the stocker to start and warm up, then plug in the XR box. oh, and by the way-If you want cheap power pull the lid off your air box, get a K&N and rejet your carb. Roughly 3hp for under $100.00!

smokin01'400
07-31-2001, 12:40 PM
Jay- thanks man. it didnt hurt your motor when it was stock? yeah, i am looking for top end since i am think of gearing it down to smoke everyone on trails. i already have the k&n air filter, it's not on though, in the box. i was gonna get a jet kit but until i get the PC pipe. my dealer to me to keep the stock air filter on since the k&n lets in too much dirt and would ruin the valves. he also said no ari box mods, but now after reading all the airbox posts on this board, i feel safe about doing them to the air box since i have your help. later keep us this great site. :devil

MARCUMS ATV
07-31-2001, 08:27 PM
I have sold hundreds of my Unlimited Rev Box and have yet to have one complaint. No one has ever grenaded a motor with one. They allow the over engineered honda motor to achieve its full potential. I have run one on my 400 since 99. My box advances your timing 5 degrees also. It is not a magic box that will give you massive horsepower but it will make a significant difference in allowing you to gain more power from your gearing meaning you can pull each gear longer. It also does not affect how your quad starts. It definitely makes a difference. I guarantee it.

Terry

smokin01'400
08-01-2001, 10:31 AM
wow ugys, thanks you got me confused again! lol. i was jsut on Big Guns website and they now make a Rev box for the 400's. anyone have one or can tell me what they are like. Big Gun claims they add 1 horsepower. do they others do that? hey, Marcums- how much do they cost? thanks. later

08-01-2001, 02:37 PM
I'm tired of hearing about that article. The only reason why that atv didnt have the rev box was because they built that motor for stock style revs.

smokin01'400
08-01-2001, 07:41 PM
hey, 426. if you dont like reading about it, then dont. go bug someone else. not all of us are rich like you and can put a 426 kit in our 400s, so we try to use cheaper mods. and i aint jeremy mcgrath so i wanted to expand my knowledge on something, is that a sin? didnt think so. later:macho

08-03-2001, 07:37 PM
RENTHAL BARS, WHITE BROS REV LIMITER, K&N FILTER AND ALL THAT ****, YOSHIMURA PRO SERIES EXHAUST SYSTEM, AC FULL LENGHT SKID PLATE, DG A-ARM GUARDS, DG FRONT AND SIDE FRAME GUARDS, PURESPORTS AND DOUGLESS BILLET BEAD LOCKS ALL THE WAY AROUND, ADN I POUND THE **** OUT OF IT.

400exRacerX
08-03-2001, 07:42 PM
yo man calm down with the language, what are we 3 years old here?

smokin01'400
08-03-2001, 09:29 PM
sorry guys, i guess i was a little p*ssed off at the time that i posted that. sorry 426, no flame intended. also, i posted this before a few posts up on the page.....what about Big Guns rev box? their website says it adds 1 hp. dot he others do that? later:cool: