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Big bore in my 300ex or bigger bike?
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Posted by: hondaex420

Right now i have a 300ex bored to a 330 but its not fast enough to me. I rode dirtbikes my whole life and traded me little 80 for the 330. I raced my sisters b/f's stock 400ex(only K&N filter) and of course lost but only by about 2 quad lenths. So i'm thinking about either selling it and getting a bigger bike or getting the biggest bore i can(390)...what should i do???!?!?!?!??!

Posted by: hardkoratvmxr

prolyl move to a bigger bike because after 330 and it starts losing reliability

Posted by: Jr_300ex

Id go wiht a bigger bike like a 400ex or an R. I dont know what kind of reliability you get with the the 390 kit.

Posted by: hondaex420

yea that is what i was origionly thinking of doing. i want a 450r, my bother has one its fast as hell..but i cant afford it ..soo i'll probly get a 400ex

Posted by: dork

i've run a 380 kit for a year and a half, no reliability problems to speak of. and thats with a season of ice racing. if you use good parts and maintain them, they'll run for a very long time. remember, with the bigger kits like this you're running the beefier rod, and the stock rod is the weak point on the 300ex, so thats eliminated. the biggest problem is keeping the clutch from slipping, springs will usually solve that though.

and i go by stock and piped 400ex's, and run with the 416's. but if you want more potential, obviously go with the bigger machines. just don't count out the 300...

Posted by: hondardr4life

I don't know man. My 330 beats piped 400ex's???. Maybe the motor need freshened up

Posted by: 300ex73

Well, there could be more you could do to enhance the power of the 330 kit. What kind of exhaust do you run? Because I doubt a standard 300ex exhaust works that well for a bored out motor. Try getting a Sparks X5 pipe, it's designed for big bore 300's. Has the head been ported? If not, that could make a world of difference. Cams could help as well. Are you running a larger carb? If not, grab a 400ex carb off Ebay. And what's your tire size and gearing?

I honestly think that if it was all setup correctly, you oughtta be able to take the 400. I can run with some stock 400's, and my motor is stock. Just exhaust, filter, jetting, and some gearing.

Posted by: hondardr4life

I talked directly to Sparks and he said that the x-5 is too large of a pipe for a 330 kit. Thats why I have the x-4 on mine.

Posted by: 300ex73

Either way, there's something wrong if he's got a 330 kit and can't beat a stock 400.

Posted by: 300ex-boy

just drop a 350x engine in there

Posted by: hondardr4life

Oh yea, there is def. somethign wrong if his 330 cant take a stock 400. Mine is dead even, actually I pull away a little, from a z-400 with a yoshi slip on. Are you sure its a 330? Do you have the stock piston to prove it? Maybe it was bored .30 over and the kid before you thought that it was a 330

Posted by: quadfamily

well you're trying to make 330cc's breath through ports, carb and cam made for 282cc engine. Keep your exhaust and get a cam, 400EX carb and have the head ported. It should fly then. What's your compression ratio?

Posted by: Cody_300ex

quote:
Originally posted by hondardr4life
I don't know man. My 330 beats piped 400ex's???. Maybe the motor need freshened up .

My 289 beats stock 400exs. He needs to P&P the head, cam, carb rev box and all those other goodies.

Posted by: hondardr4life

lil300exkid, What kind of gearing and what size tires are you running?

Posted by: roostin_dale

my 298 would spank 400ex's...

I still have a few parts forsale that could freshen up yours...Mikuni 38mm Flatslide carb (will really wake it up)..and a FourStrokeTech unlimited rev box....This should help your motor alot..let me know

Posted by: hondardr4life

Ok, I'm interested in that stuff too. How much for each one of them? And would that carb and a 400ex carb be much different, because I don't know how much you want for that, but I can get a used 400 carb for $60- $80.

Posted by: roostin_dale

quote:
Originally posted by hondardr4life
Ok, I'm interested in that stuff too. How much for each one of them? And would that carb and a 400ex carb be much different, because I don't know how much you want for that, but I can get a used 400 carb for $60- $80.

you will get more power from this carb. I want $55 shipped on the rev box...and I want $80 shipped on the carb. I have $40 worth of extra pilot and main jets also that i will sell for $25 shipped..

Posted by: hondardr4life

Will this carb be any better than a 400ex carb? And I have had no experience with rev boxes, will it give me a good bit more power too. I will let you know on those parts, I need to buy a different rear sprocket because my engine revs out of gears wayyy to fast, and I might be needing a new clutch soon, but I will get back to you.

Posted by: roostin_dale

quote:
Originally posted by hondardr4life
Will this carb be any better than a 400ex carb? And I have had no experience with rev boxes, will it give me a good bit more power too. I will let you know on those parts, I need to buy a different rear sprocket because my engine revs out of gears wayyy to fast, and I might be needing a new clutch soon, but I will get back to you.

oh my, you have a 330 with a stock rev box? wow! your 330 will not rev any more than stock, all an aftermarket does is give you unlimited rev, so your engine can rev higher.

You will feel alot more power gains with this carb rather than a 400ex!..I have a brand new 38 th rear sprocket and some slightly used 36th's....

Posted by: hondardr4life

Ok, well I am looking for like a 36, preferrably a 34, but a 36 will work. That carb is for a 300ex, right?