I bought a 300ex and was told it was very fast. I bought this quad without researching it. It is a 2005 trx 300ex bone stock. This thing is a dog. feel like I am riding the old 200x. Is there any way to bring this quad to life?? I love going fast and would love to find a couple of mods to get me there.

 

You could do the norm, exhaust and jet, airbox lid remove, filter. But if it seems like a dog to you its not going to feel fast no matter what you do. In other words you could potentially spend alot of money and still not be satisfied. I would just live with it until you can sell it and buy something bigger.

 

ok thanks. I have a few Q's. Exhuast? slip on or full to motor? Brand? How hard is it to jet a 300ex? I should remove the air box lid? What type filter? Thanks for the help. Which of these will do the most for power?

 

First off, this thing needs a header! The tiny little stock one is pathetic.

I put an FMF PowerCore 4 on mine and it came with a header...no extra charge! EHS Racing airbox lid (with Outerwears), UNI foam air filter (I don't trust K&N), and a rejet. These will all help...

Also, consider a gearing change????

 

Thanks for the advice. Will this make a considerable difference? How hard is it to jet?

 

Jetting is very simple,and you can acheive great results with jetting if you have a good after market header and muffler on a trx250x/300ex. Dont forget to make sure the timing is set perfect and the valve are set withen spec's as well. One would not think how important valve adjustments are but trust me its as important as the correct jet settings.
For me i went with a bit smaller rear tires (from 22's to 20's) and kept with the 13 font and 38 rear sprockets. Gives me a balance of low end torqe and speed.
I have a 250x, complete custom cobra header and muffler, run 132 keihin main jet and have needle set 3 notches from the top. Air mixture screw 1 and 3/4 turns out. Run K&n slip on , open airbox ,It is bored 60 over and been ported but i would have to think very close to what a 300ex would be needing to wake it up..

A few pics of it http://s185.photobucket.com/al...urrent=91trx250x_7.jpg the warrior its pictured with never stands a chance when where out riding and my neighbor gets so pissed [img]i/expressions/face-icon-small-smile.gif[/img]

I been messin around with the 250x and 300ex's for a long time if you need some info just ask..

 

Thanks. I guess it isn't a complete dog it does have tourqe. But what honda 4stroker don't. Is the header pipe and exhuast a good start? Will that and a airbox removable make a noticable difference? The jetting might be something I have a honda shop do. I dont know much about carbs and would hate to hget it all out of whack. Is a cobra exhuast a good choice for a 300ex. And is it safe to buy one used if its not beat up? They dont go bad do they? Thanks for all the help.

 

The 300 really shines as a tight trail quad! It has a torquey low end, and the engine doesn't mind being lugged down. Plus its smaller frame lets it fit easily between the trees. On both the 250's and 300, first thing I did was put 20" rear tires on it...for even more low end....

The machine is a little out of its element at very high speed.....

 

Or go find a good 350x motor and build it for your quad.I have a friend with a 250x quad with a little port and valve work and some other stuff done,and it keeps up with my kids 400ex !