Honda TRX ATV Forum banner
1 - 10 of 10 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
hey all thanks for having me. I don't really do forums so forgive please. I just bought my first atv an '05 trx 300ex. I think the state switch needs replacing or at least jumped to get it running. it needs a lot of tlc. what is the best manual to get for this machine ? thanks in advance.
 

·
Super Moderator
Joined
·
4,479 Posts
hey all thanks for having me. I don't really do forums so forgive please. I just bought my first atv an '05 trx 300ex. I think the state switch needs replacing or at least jumped to get it running. it needs a lot of tlc. what is the best manual to get for this machine ? thanks in advance.
The best manual is the factory manual - I have it in PDF and can email it to you - just send me your email address in a private message and I will send it to you
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #3 ·
The best manual is the factory manual - I have it in PDF and can email it to you - just send me your email address in a private message and I will send it to you
Hello, my name is Marvin, my email is [email protected]. Also, if you don't mind, my quad came with a yoshimira exhaust, I'm going to assume the carb was rejetted for the exhaust. If I get a carb rebuild kit do I need to specify that or just reuse my current jets ? Secondly, I'm looking into getting an aftermarket cam, do they make performance cams for this machine ? Thank in advance for your time and consideration. Respectfully,
 

·
Super Moderator
Joined
·
4,479 Posts
Marvin, my name is Steve - don't assume the carb has been rejetted - jetting is not usually necessary for a change of the exhaust - changes to the intake have a more dramatic effect on the jetting than changes to the exhaust. Get the carb apart and check the jetting against the specs in the manual, then you will know if the jetting has been altered. Hot cams has a Stage 1 cam for $185 Megacycle cams and Megacycle can regrind your stock cam into a high lift cam or may have off the shelf cams for you 300. Just to make your search easier, the cam is the same for 87-92 TRX250X and 93-09 TRX300EX.

PS - sent the manual also - if it says you need permission to view it, just request permission and be patient - I'm off here until tomorrow.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #5 ·
Marvin, my name is Steve - don't assume the carb has been rejetted - jetting is not usually necessary for a change of the exhaust - changes to the intake have a more dramatic effect on the jetting than changes to the exhaust. Get the carb apart and check the jetting against the specs in the manual, then you will know if the jetting has been altered. Hot cams has a Stage 1 cam for $185 Megacycle cams and Megacycle can regrind your stock cam into a high lift cam or may have off the shelf cams for you 300. Just to make your search easier, the cam is the same for 87-92 TRX250X and 93-09 TRX300EX.

PS - sent the manual also - if it says you need permission to view it, just request permission and be patient - I'm off here until tomorrow.
I'm having hell of time with procrastinating getting a parts list together
 

·
Registered
Joined
·
3 Posts
I'm sorry, but that's on you - I can't help with that.
Good day Steve, so time and money and parts later, I'm into the buttoning up phase the last major thing I need to do is WAAAAAAAYY out of my wheel house. The carburetor. This was my first time ever installing a rebuild kit, my first time doing anything to a carb other than giving it a good spray down cleaning. iIn the tear down phase, the pilot screw was only 2 turns out with a 38 slow and a 118 main jet. According to the manual this appears to be a high altitude set up. In rebuilding the carb I used to #38 slow and #122 main that is factory and came with the kit, I also returned the pilot back to 2 1/8 turns out. I should add that the only thing I'm aware of that isn't stock is the FULL Yoshimura exhaust and the dozen or so holes drilled in the air box lid.
Thank you in advance for your time and attention to this matter.
Respectfully,
 

·
Super Moderator
Joined
·
4,479 Posts
So what do you need to know? the pilot screw setting is not finite - 1 3/4, 2, 2 1/8, 2 1/2 they are correct depending on engine operating temp, air density, fuel quality, humidity and other variables. The pilot screw is for a smooth consistent idle. It will be different on each carburetor. The setting in the manual is the initial setting. To set it correctly, you have to ride the vehicle about 15 minutes to get it up to operating temp. In the shop we let it idle with a box fan blowing air across the engine for cooling. Connect an accurate tachometer and set the idle at the desired speed. Then using a special 90 degree screwdriver, turn the pilot screw in in 1/8 turn increments pausing 5 to 10 seconds between adjustments. When the idle speed drops 50 RPM, turn the pilot screw out one full turn and that is the final setting.

With an after market exhaust and holes in the air box, it should be lean across the RPM range and the pilot jet could be bumped up to a 40 and the main jet just has to be adjusted until it runs right at full throttle. If it falters in the mid range (1/4 to 3/4 throttle opening) then the slide needle needs to be adjusted up or down depending on the mixture (down for rich and up for lean) - all you can do is ride it, determine how it performs and adjust accordingly.
 

·
Registered
Joined
·
3 Posts
Thanks for the info I'll have to take it to a shop. I don't see myself having much use for a tach otherwise and I'm doing most of this in my living room. What state is your shop located in ?
 

·
Super Moderator
Joined
·
4,479 Posts
Illinois - if you filled out your location when you registered, your screen cursor may be parked over the nationality flag under your Avatar and the location will appear. My location is 'Smack in the middle of Illinois'.

You might consider shipping the carb to me for servicing and then all you have to do is install it and make some minor adjustments. I can advise you of the problems discovered and recommended repair. Many times no parts are even required, just a thorough cleaning, proper assembly and correct adjustment. Sometimes they are beyond repair due to water or alcohol damage, but they are the exception. Most unrepairable carbs are off neglected vehicles that have sat unused for a year or more unprotected from the elements.
 
1 - 10 of 10 Posts
Top