Best 03 carburetor

[RatX13]

Title says it all, I want a better carb on my 03 450, right now I just have stock (mom asked me what I want for my birthday and that's all I can think of lol) my bike is by no means insanely built, it has a full rebuild that is being done as we speak (hot rods heavy duty crank, kibblewhite valves, pro-x standard bore piston, yunno nothing crazy) I also have a uni-air filter, PowerCore4 muffler and a PowerBomb header. I want to do my carb next. I have a budget of about $300... I have never messed with the carbs on any of my bikes I think the 03 is a 39mm..? All I know is I want serious throttle response and flow all the way through the rev range so please help my decision, thanks

[Diggla117]

Title says it all, I want a better carb on my 03 450, right now I just have stock (mom asked me what I want for my birthday and that's all I can think of lol) my bike is by no means insanely built, it has a full rebuild that is being done as we speak (hot rods heavy duty crank, kibblewhite valves, pro-x standard bore piston, yunno nothing crazy) I also have a uni-air filter, PowerCore4 muffler and a PowerBomb header. I want to do my carb next. I have a budget of about $300... I have never messed with the carbs on any of my bikes I think the 03 is a 39mm..? All I know is I want serious throttle response and flow all the way through the rev range so please help my decision, thanks

I think tuning, exhaust and a cam is what your really asking for here..

Only other carb I know of for that bike is the edelbrock series and I'm pretty sure that don't make them anymore

[RatX13]

I think tuning, exhaust and a cam is what your really asking for here..

Only other carb I know of for that bike is the edelbrock series and I'm pretty sure that don't make them anymore

Well like I said I already have a full exhaust. I am eventually getting a stage two hot cam when I save up enough. I didn't know there was only one other carb for it. I've just heard of people getting different carbs for there bikes to up the performance. (I'm no bike guru just a kid that likes to ride) If there isn't a carb I can get then I'd want to change the jets in the one I already have

[danfor50]

Higher compression ratio piston. Best bang for buck.

Sent from my intergalatic communicator

[RatX13]

Higher compression ratio piston. Best bang for buck.

Sent from my intergalatic communicator

My mechanic told me they dont make a difference unless the head is ported and bored. Even if it does, Im not looking for a piston, I'm looking for a carb lol I already have all my parts and it's already being rebuilt

[FORMA MOTO]

The stock carb is fine when properly set up.

 

https://www.thumpertalk.com/topic/1053317-06-crf450r-still-bogs/?hl=%2Baccelerator+%2Bpump#entry11143305

[Diggla117]

^true that. 13.5 high compression piston will wake it up.

Man jetting is everything. ESP if you never rejetted after you put your exhaust on or ever properly had it jetted to begin with.

[Diggla117]

Your mechanic sounds like a very knowledgable guy.. LOL.

[EnglertRacing]

MMMMMKKKKKAAAYYYY

OEM > Hotrods

CP High comp > CP > JE >Weisco > OEM > PROX

I put a 12.5-1 CP piston that i ordered with the "custom option" lateral gas ports

and then i cut the cylinder to achieve 0.039" quench. the result was 12.9-1

made a significant difference.

 

Kibble white good, but a performance decrease can be expected with stainless valves and the heavier valve springs.

in my bike id use oem or delwest TI with moldstar seats, and PAC valve springs and TI retainers.

 

and your carburetor is fine.

i think they made a few refinements on later carbs like a replaceable leak jet (you can drill your own leak orifice if your good)

but do some research and find out what you can do to improve your accelerator pump circuit.

get a merge adjustable fuel screw.

get a new vac release plate from a Yamaha dealer (Honda sells it with other parts you don't usually need)

think about a JD jet kit.

[RatX13]

MMMMMKKKKKAAAYYYY

OEM > Hotrods

CP High comp > CP > JE >Weisco > OEM > PROX

I put a 12.5-1 CP piston that i ordered with the "custom option" lateral gas ports

and then i cut the cylinder to achieve 0.039" quench. the result was 12.9-1

made a significant difference.

Kibble white good, but a performance decrease can be expected with stainless valves and the heavier valve springs.

in my bike id use oem or delwest TI with moldstar seats, and PAC valve springs and TI retainers.

and your carburetor is fine.

i think they made a few refinements on later carbs like a replaceable leak jet (you can drill your own leak orifice if your good)

but do some research and find out what you can do to improve your accelerator pump circuit.

get a merge adjustable fuel screw.

get a new vac release plate from a Yamaha dealer (Honda sells it with other parts you don't usually need)

think about a JD jet kit.

Now that you're telling me this I feel pretty ripped off by my mechanic.. I was actually looking at a 13-1 CP piston on tokyomods and my mechanic told me not to get crazy.. so he got me the prox because it's the same as oem, I did the kibblewhite because they were cheap and they last long then price was obviously the reason for the hot rods crank vs oem. I feel pretty shitty about my bike now.. there is this think called a "Power Bowl 2" on Rockymountain that says will fit my carb and wake it up, but is it worth the $200? Does anyone know what I'm talking about? If I got that I'd probably still do a JD jet kit with it

[Diggla117]

Now that you're telling me this I feel pretty ripped off by my mechanic.. I was actually looking at a 13-1 CP piston on tokyomods and my mechanic told me not to get crazy.. so he got me the prox because it's the same as oem, I did the kibblewhite because they were cheap and they last long then price was obviously the reason for the hot rods crank vs oem. I feel pretty shitty about my bike now.. there is this think called a "Power Bowl 2" on Rockymountain that says will fit my carb and wake it up, but is it worth the $200? Does anyone know what I'm talking about? If I got that I'd probably still do a JD jet kit with it

You can order cp pistons directly from them and you want a 13.5

The power bowl two will help your carb a lot.

Jd jet kit is a waste of f'n money, the only good thing about it is it comes with all your size jets... And those are cheap as hell anyways.

You can listen to who ever you want but I went down that road a few years ago and ended up redoing it right.

R&d Powerbowl 2 (amazon prices was cheapest)

Ncvs needle (partzilla.com)

Rebuild kit (eBay)

Vacuum plate and vacuum plate seal (partzilla under 08 yz450f)

R&d REMOTE fuel screw, any other fuel screw is a waste of time money and patience.

And nothing wrong with hotrods cranks at all.

Edited August 5, 2014 by Diggla117

[RatX13]

You can order cp pistons directly from them and you want a 13.5

The power bowl two will help your carb a lot.

Jd jet kit is a waste of f'n money, the only good thing about it is it comes with all your size jets... And those are cheap as hell anyways.

You can listen to who ever you want but I went down that road a few years ago and ended up redoing it right.

R&d Powerbowl 2 (amazon prices was cheapest)

Ncvs needle (partzilla.com)

Rebuild kit (eBay)

New throttle plate (partzilla under 08 yz450f)

R&d REMOTE fuel screw, any other fuel screw is a waste of time money and patience.

And nothing wrong with hotrods cranks at all.

Thanks man big help!

[EnglertRacing]

Well don't feel shitty about it.

The kibble white stuff is good.

But did you get their springs??

And in a way your mechanic was right. The yosh Shit is overpriced. So is pc. It's good stuff but guess what their pistons are marked up cp or je. Their valves are marked up exeldyne or delwest. A better place for parts is crfs only.

Edited August 4, 2014 by EnglertRacing

[RatX13]

Well don't feel shitty about it.

The kibble white stuff is good.

But did you get their springs??

And in a way your mechanic was right. The yosh Shit is overpriced. So is pc. It's good stuff but guess what their pistons are marked up cp or je. Their valves are marked up exeldyne or delwest. A better place for parts is crfs only.

I just got all four valves because the mechanic got me oem springs