07 TRX300EX Upgrades

[timb052]

I just got a TRX300EX about two months ago and i am dying to do something to it. I want to do some upgrades to improve performance.

I have been wanting to put 20s on the back. What sprockets do i need to get to make it the back to stock. Also what is the best tires to get.

I am completely dumb when it comes to fourwheelers, but I am fairly new to them.

Also I am still in college, so I want to keep the cost down.

Timbo

[bwamos]

20's on back.

Raise the front to a 14 tooth (will have to shave the chain slider on the case).

Or, drop the rear to a 36 tooth.

14/38 should give you close to stock final ratio on 20's
13/36 will give you just slightly lower gearing that stock on 20's.

Bolt-on Bang for the buck. Pipe, Filter, Rejet.

After that, suspension, IMHO.

[timb052]

what does rejetting mean? I mean i know it has to do with carb, but that is something i dont know anything about.

[bwamos]

The carb is pretty simple once you figure it out.

There's 3 main circuits (or positions).

Pilot wich controls idle-1/4 throttle ranges
Slide and needle jet wich controls 1/4-3/4 throttle
Main Jet which controlss 3/4 - Full throttle.

The pilot jet controls how much fuel is let in at idle.
The needle is tapered and allows less to more fuel in as the slide raises (when increasing throttle).
The main jet is what controlls the maximum amount of fuel let in when at full throttle.

Generally if you are flowing more air (filter and exhaust), you need to compensate with more fuel. More air+more fuel at the right ratio = more power. ;)

Simplistic of course. No need to get into interpreting bianary language of a watch processor when all you want to do is change the battery.

Here is a great article.
All carbs vary a little but the basics are the same.

http://www.duncanracing.com/techfaq/Tech_keihin-carburetion-jetting.phtml

Or you can do it the easy way and spend an extra $30 and get a jet kit. ;)

[timb052]

thanks for the info.

Now what exhaust is the best to get? I want something good but not something that is going to expensive.

I am wanting more power but i dont know where to start.

[born2ride14]

there are great deals on exhausts on ebay theres a guy who sell jardine slipp-on exhaust they are good but if u got $400 get a sparks

[07250ex]

Hey timb can you post like a bunch of pics of your bike i really like the way the new 300ex looks

[SET THE STAGE]

first thing i would upgrade on your 300ex would be the tires for sure. get maybe some 20 inch holeshot HD's on the rear. totally worth it. then once you get some extra cash, work toward an exhaust (sparks or a supetrapp 4" race system preferably)

from there i'd upgrade the front suspension. a lot of people do a conversion for their front a-arms where they use 400ex a-arms on the front (including the spindles, brakes, front hubs, tie-rods, etc.) and 400ex shocks. but in order to do that, you have to buy a shock relocator which you can get for about 50 bucks, i believe.

doing that will give you a wider front end (more stability), longer shocks/more shock travel, and just a better front end altogether.

[rrntheboyz]

SET THE STAGE.....By doing that to the front end, should he widen the back too? And if so, what the recommendation on that??

[SET THE STAGE]

Originally posted by rrntheboyz
SET THE STAGE.....By doing that to the front end, should he widen the back too? And if so, what the recommendation on that??

you wouldn't necessarily NEED to widen the back, quads generally handle better with a slightly wider front end than the rear. but a +2 axle in the rear would work GREAT.

g-force has axles for 200 dollars from rockymountainatv.com. they aren't the best out there, but i don't think you plan on racing nationals or anything by the sounds of it so i think it'll be okay.

[JIMFROMTEXCO]

or a 350x axel and hubs its about 2 1/4" wider and alot cheaper then buyiing a brand new one.

[SET THE STAGE]

aren't 300ex hubs wider than the trike hubs, though? i know that's the case on my 200x and the 250r's. 400ex/300ex/250x/450r hubs stick out about an inch and a half wider than the old trike hubs.


is the 350x axle a straight bolt up?

[timb052]

thanks for the advice guys. Didnt get on here any this weekend, i went out riding saturday, just rode on some power lines. It does pretty dang good. I wasnt expecting much out of it, but it exceeded my expectations. It is a good factory bike to me.

Timbo

[timb052]

I doubt i ever will, but how would someone get into racing quads?

[bwamos]

Get a kill switch, sometimes nerfs, a helmet, goggles, gloves, and find a race to go to and pay the racers entry fee.

Most races (around here anyway) you just show up pay the fee, roll through inspection, and get on the starting line.

[timb052]

well that isnt all that bad. I would probably get blew away unless i was racing other 300s, then i would probably still get beat, but i guess you have to start somewhere. Thanks for all the information guys