need more speed

[4fiddytrx]

I have a 2004 honda 450 with a stage 2 cam, LRD pipe and header, knn air filter,and jets. Is there other small mods to make my bike faster that dont cost a ton of $$$.

[pro-rider46]

could you give us a budget range possibly?

[4fiddytrx]

i could probably spend about $600. could that do anything?

[the Z Man]

Go with a different needle, Sparks or HRC, lid off the air box, port the head, go up 2 teeth on the rear sprocket for torque down 2 teeth for speed.

[d3ktrix]

12.1 Piston
Head porting

FCR Carb

turbo it:D

[400exrider707]

You should be more clear what you're looking for here. When you say, "faster".... do you mean more top speed, or more acceleration? More top speed can only be achieved using different tire sizes and changing gearing. Acceleration can also be achieved using different tire sizes and gearing, and also through more power, but it will not give you a higher top speed.


Small mods to make your bike Faster (top speed) would be different sprockets. Taller on front or smaller in rear will yield more top speed. Try dropping two teeth on the rear sprocket.

[4fiddytrx]

would porting the head make my engine less reliable? what about a 12:1 piston? What would you think about a different carb or better pipe and scilencer?

[JimmyHoffa]

Porting the head really doesn't affect reliability. One school of thought (the general knowledge one) would say that a 12:1 compression piston is somewhat mild, and will only affect reliability mildly, and is well worth the performance gain in the eyes of many.

The other school of thought (mine, the specific one) would say that you bought a 1st gen 450r, which is pretty much a bottom-end hand grenade of some sort waiting to happen, so you should probably not tempt the crank/rod with any additional stress unless you do something to band-aid the design flaw that cannot be worked out of the bike completely ever, no matter what you do. Personally, I'm staying near the stock CR for the life of my engine/bike. (...which may be shorter than my pet fruit fly. :ermm: )

[JimmyHoffa]

As for the pipe and silencer, I wouldn't hesitate. I just finished (as in a few minutes ago) putting on my new HMF QRS full system. Not only does it look outrageously sweet, I'm pretty sure I got about 1,000,000 ft-lb. at 2K RPM compared to the stocker. Way torquier. Smart people (e.g. 400exrider707) correct me if I'm wrong, but I would think a new carb would be fairly far down the list of things to get... At least when compared to the other things you mentioned, especially when bang-for-buck is a consideration.

[4fiddytrx]

well i already have a lrd pipe and silencer.Are you saying i should look into something better? if so what do you think? i bought my quad over a year ago used with every thing on it,and i dont realy know to much about after market parts.

[Sjorge450R]

Originally posted by JimmyHoffa
As for the pipe and silencer, I wouldn't hesitate. I just finished (as in a few minutes ago) putting on my new HMF QRS full system. Not only does it look outrageously sweet, I'm pretty sure I got about 1,000,000 ft-lb. at 2K RPM compared to the stocker. Way torquier. Smart people (e.g. 400exrider707) correct me if I'm wrong, but I would think a new carb would be fairly far down the list of things to get... At least when compared to the other things you mentioned, especially when bang-for-buck is a consideration.

exactly. I carb is one of the last things you need to worry about right now. That comes after the motor work. IF you were to change the carb, you would be over killing the motor.

[bloodmoney23]

you want small cheap mods. do 18" tires on rear which will take away top speed but get you to top speed a hell of a lot faster. and send your head in to get ported. The only hesitation people have about high compression pistons is wether or not you can get race fuel. 12.5:1 is the highest you can go with pump fuel. 13:1 and above you need race fuel. I run a 11.5:1 with 93 pump and octane booster. I have a 2005 and have not had a single crank problem yet. But liek he said some go and some dont. hit or miss pretty much.

[JimmyHoffa]

Actually. 12.5:1 is not as high as you can go on pump gas. There are so many other things that affect how an engine runs on certain octane ratings that I don't even want to start talking about it. (Part of the reason I don't want to say any more is that someone smarter than me deserves to do so, and I will probably never get to the thermodynamics classes that can explain, with solid math, why this is true.) Look up the 2008 RM-Z 250's CR if you want to see a hard hit. I think it's 13-and-some-change to 1.

Also, I think people hesitate to put high compression pistons in for a variety of reasons (anyone feel free to add or subtract from this list):

1.) Measurably increased stress on almost every moving part in the entire bottom end of your engine, and increased top end pressures and stresses.

2.) Yes, the engine is more prone to detonation and may require a "finer brew" of fuel.

3.) You have to take your engine apart, and darn well better replace almost every gasket you touch. The top end isn't too bad, actually. However, some find this process complicated. It challenges me. I can do it, but I'm slow. (I get it right.)

4.) Many people trust OEM components more than high performance aftermarket accessories of any type.

5.) You should probably step up your top end maintenance intervals.

Also, I solved the gearing problem by buying sprockets. Personally, I have a pile of sprockets I can slap on my bike at any moment instead of having to break the bead on my two rear tires to "tweak my gearing." Also, two tires are about $100, and a front sprocket is about $9. Penny saved, penny earned.

[bloodmoney23]

good call on the tires and sprockets. i have a good handful of front sprockets now too. from 16 down to 12. they are more like $20.00 though. (I run Sunstar or Renthal only) the smaller tires though also keep the fourwheeler lower to the ground, which is good for MX, but this kid has yet to respond on what kind of riding he is doing so if trail riding smaller tires wont really help. And the 08 LTR is a completely different bike so the physics are different therefore it can run a 13:1 piston on regular fuel. But, for the physics of the 05 450R, i would need to run race fuel with a 13:1 or higher piston. its just safer.

[JimmyHoffa]

For the '05 engine with that valvetrain, I'd agree. The compression ratio can't be too terribly high. However, many other things can be done to any engine to change it's tolerance of fuels. I'm not an expert, so I'll stop there. The 450r engine isn't completely incapable of running premium pump juice at 12.5:1 - 13:1, there are just a few things that need to be done to get it to not blow up. (It's going to anyway... oh well.) Those are some top of the line sprockets. I just run JT or Primary Drive. Most good stores can get them (at least Primary's) for you for about 8-9 dollars.

With smaller tires you reap the added benefit of less sidewall (which means less sidewall to flex) and a lighter carcass. This equals less rotating mass, and everyone knows what that equals... It's just a little more expensive and completely impractical on any type of technical trail. I would guess that 4fiddytrx doesn't strictly race, so this may not be the best route. I'm in the same situation. Little of both, and fairly poor for a quadder.

[bloodmoney23]

well i know its kinda impractical and a little expenisve but im poor and found a way to afford it. I just bought 18" tires on Baja 9x9's and 20" tires on the same baja 9x9s so i have 2 sets. So when i race i run the 18s and when im just messing around i throw the 20s on. Like i said, not everyone would wanna do this but it does help out. Im not big on the JT or lower brands cause ive had too many teeth break on those. thats when i started with the renthal and sunstars. anyway, i think we can both agree that if this kid wants more speed he needs to change his gearing and probly some head work or a stroker crank.

[JimmyHoffa]

speaking of... Do any of the stroker cranks have a better reputation for longevity than the pre-late '05 cranks? I know that even Honda's "fix" isn't a real fix. Also, bloodmoney, apparently some late '05 R's have the updated crank, which could explain why your engine is happy. I wish mine was.

[4fiddytrx]

i mainly ride in the sand, and thats where i want more speed. do you think smaller paddles would be good idea or would it slow me down because of ground clearance. i think it would be faster to changes tires instead of sprocket.right now i have a 13 tooth on my front and stock in the rear.

[400exrider707]

Originally posted by JimmyHoffa
speaking of... Do any of the stroker cranks have a better reputation for longevity than the pre-late '05 cranks? I know that even Honda's "fix" isn't a real fix. Also, bloodmoney, apparently some late '05 R's have the updated crank, which could explain why your engine is happy. I wish mine was.

Nothing changed on the cranks, they just added a collar to prevent crank bearing wobble. I've seen many more rod bearings go than crank bearings myself. If your crank bearings are bad, they usually go within the first hour or less. If you get more than a season or two out of crank bearings, you are pushing your luck anyways in my opinion. These are high performance motors, and need high performance maintainance.

As far as reliablity, I will run an OEM crank any day of the week, at least until I can afford a Falicon supercrank. Very nice units.

[d3ktrix]

Originally posted by 400exrider707
Nothing changed on the cranks, they just added a collar to prevent crank bearing wobble. I've seen many more rod bearings go than crank bearings myself. If your crank bearings are bad, they usually go within the first hour or less. If you get more than a season or two out of crank bearings, you are pushing your luck anyways in my opinion. These are high performance motors, and need high performance maintainance.

As far as reliablity, I will run an OEM crank any day of the week, at least until I can afford a Falicon supercrank. Very nice units.

You'd really consider 2 seasons the limit for crank bearings?
Never herd this before, I figured the bottom ends were like cars and lasted forever. lol

[bloodmoney23]

well im on my 3rd year for crank bearings but i do feel like im pushing it thats why i want bottom end rebuilt. well if you are running sand do you want more speed or top speed faster. like D3 said in another post, I would do 20"tires and 15/38 sprockets. with that setup i still had good bottom end but not enough for MX, i felt i didnt lose much bottom end from full stock though. but gained a bit on top speed. i suck at explaing but with exhaust, intake, cam, piston and 15/38 gearing with 20" rears, it still had more bottom end than stock and scooted out alot faster once i hit 3rd 4th and 5th. It will add about 5-8 MPH faster with the 15 front. and with the 13 you are full bottom end MX ready pretty much. which you will get to top speed faster but lose about 10-15 mph. i hope i didnt screw nothing up this time. like i said im horrible at explaining. and it only took me about 10 min last night to change my front sprocket.

[JimmyHoffa]

I just went to Falicon's site and I changed my pants immediately afterwards. Quite an operation. Nice stuff, but since I pretty much rebuild my bike every year, I might as well just put OEM stuff in. I'll be in the engine anyway, and It'd probably be cheaper just to go with the 193 dollar OEM setup whenever I crack the block open, than to go with their $399 supercrank heavy setup. (which is what I'd do if I went with Falicon since I basically only care about reliability.) I'll give the thread back now. Here ya go. :p

[4fiddytrx]

well i think iam going to get a 15 tooth sprocket and see how i like it. thank guys