302 big bore, any reviews?

I'm interested in a big bore for the 250F and have not seen any reviews on it, anybody have one

I got my a$$ kicked by a 49 year old man with the "Ice Cube" cylinder... He was pulling me hard on straight aways, so I would say that is pretty fast ! ! ! !

Thank you Scooter for the post. I'm a 42 year old old guy and my 450 would just wear me out to quick, so I'm looking to do a CRF250 into a 302 or a RM250F into a 315(if the '06' has an aluminum frame) so any info is great. Thanks.

I am 32 and 190lbs... I put the hot cam in my CRF250 last week, man what a difference. It pulls alot harder. I too had a CRF450 and just couldnt hang on for an entire moto. I REALLY like my 250, even stock. But as heavy as I am, I just needed a little more "umph" if you know what I mean.

Although big bores do make more power.....the 302 kit is pretty expensive.

I had Crowerpower regrind my cam....made a huge difference...much more than a pipe would do.Makes about the same power as a 280 kitted bike.

I am 32 and 190lbs... I put the hot cam in my CRF250 last week, man what a difference. It pulls alot harder. I too had a CRF450 and just couldnt hang on for an entire moto. I REALLY like my 250, even stock. But as heavy as I am, I just needed a little more "umph" if you know what I mean.

I am getting some additional "oomph" via a cleaned up 2005 head, a 13.5:1 piston, along with my SM1 pipe and some Ultimate-4....when RHC has his camshaft ready next month or so...I am going to get that too...porting at this point is going to be my last mod (bang for buck factor) unless I win the lottery or get a big bonus at work this month...both of which are highly unlikely :naughty:

Thank you for the reply's fella's.

I am going along the same lines I am getting whipped by the weight of my DRZ400 and am thinking of going the route of CRF250X or Wrf250, but I keep bieng told that the low end torque will dissapoint me, so I am thinking big bore kit and heavier flywheel. does this sound about right? How is the reliability of big bore kits?

thumper racing makes a 270 kit that is supposed to give you a little more oomp throughout the powerband and improve reliabilty. I have done business with them before on other bigbore kits, and they deliver what they promise. I talked to them yesterday. You could go nuts and have them do all the work and install SS valves and get away for less than $1,000 and all you have to do is put the completed motor back in the frame :naughty:

I am considering getting a 4 stroke and I'm split between a 450 and 250. I'm coming off of a pro circuit built worx 250 (2-stroke). My 250 is without a doubt the fastest motorcycle I've ever ridden (yz450f, crf450 and cr500 included). It was a former outdoor nationals bike and it's all topend--the power is totally useless. I rode a friends 04 crf250r with a 52 rear sprocket and I thought it was amazingly strong--much stronger than I expected. I don't know what kind of riding you're doing but have you considered a gearing change. I'm only a 170 (w/gear) and the 250f pulls the front end in 3rd with the new gearing--didn't before. Weigandt just got 2nd in a WORCS on a crf250! The 302 might be the perfect bike, but for MX I can't imagine anything better than a 250f.

Thanks for the reply's. I ride mostly MX, but will buy this for playriding also, it might be my last bike! I'm 42, 200lbs and stay in fair shape(not race shape), the 450 kicked my butt but was fun! I'm just trying to find an all around fun bike, and this 302 or the 315 kits seem like the best for me, light, good power, trailability(is that a word?). My budget is ok to do this(unless we have triplets in this next pregnancy, know in a week!!!) so any info is great to make my decision. My dealer is a Honda Suzuki guy so they are my only options, although I steer to the Honda first(just fits to good). Thanks again for the reply's. Wally.

If you want and can afford the 302 i say get it.But just to let you know i also weigh 200lbs and beat 450's all day long.The only place they beat me is the start sometimes.I do have a few perfomance mods.Icat,Vortex-x10 ignition,Pro Circuit Ti pipe.My bike Rips.If i keep my bike another year which i plan i will get an 05 head and go with the 270 kit.

Thanks for the reply 88, I might also be interested in the 270 kit but am steering towards the 302 right now because I think it would perfect for what I want to do. I read on one of the post's about Tom Morgan doing this kit also and he has done my suspension on two bikes and it was great, so he would be an consideration also for motor work. This will more than likley be my last bike and I might as well get what I think will be the all around best for myself! Thanks for the reply's fella's, Wally.

I've got the 270 kit on my X and it is AMAZING... Everyone that has done the kit loves it that I know of. It really wakes the bike up. There is some concern over the add'l piston weight but I don't think its an issue if you are not bouncing off the rev limiter all the time. For woods riding, it is the way to go.

For all who are interested there is supposed to be a test in the July 05 Dirt rider of the RPM CRF302 big bore kit.

I rode a friends bike yesterday with rick petersons ice cube 276.WOW!I can't belive 26cc's makes that much of a difference.I think it is way over priced but i will deffently get a big bore done this winter.

Bump, bringing this back to the top. Thanks.

I'm plan on getting a 270 kit as well.

I scare my self sometimes, I go so fast on my X right now.

But with the 270 kit it will be a SWEET trail bike.

Gentlemen......i'm A Female Local Mx Racer And I Ride An 04 Crf250r That Is Due For A Top End ( I've Had The Bike For A Year Now). I Had An 01 Cr250r That I Started Racing With. I Ride/race 2-3 Times A Week. I Miss The Power Of The 2-stroke And Am Thinking Of A Big Bore Kit For The 4-stroke To Get Some Of That Power Back. I Have An 05 Crf450r That I Love To Ride But It's Too Much To Race. The Only Mods I've Done To The Bike Is A 51 Rear Sprocket And A Dr D Pipe. So......who Can Help With Suggestions? I Would Wait For The July Issue Of Dirt Rider But I Only Have A Couple Weeks To Make The Mods. I Need To Beat The Crf450's!

Any Help Would Be Greatly Appreciated.

Call Gary at Thumper Racing.

Price for the 270 kits is less than a lot of Ti-pipe set ups and WAYYYYYYY more power across the board.

He will more than happy to talk to you, and his work is ++++++ :)

You would be amazed at what his 20cc boost does to this motor.





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