[Texn]

2005 Rancher TRX350FM

I live in Texas and am planning on taking my atv to colorado. The highest elevation I will be driving is around 7,500 ft. Should I change out a jet or something in the carb to avoid fouled plugs, or will it probably be ok? If so, what exact part do I change? I looked at the part schematics and they say nothing about diameter of the jets.

 

[b52bombardier1]

Your spark plug might blacken and get a little rich sooty deposit on it. Depending on how long you are at the high elevation, I might not worry about it.

At most, I might carry an extra new spark plug and install it if you have trouble. That way you won't potentially overheat your engine running it with a lean main jet back at your original lower elevation.

Rick

Sent from my SAMSUNG-SM-N900A using Tapatalk

 

[b52bombardier1]

Hello Again,

2005 Honda TRX350FM A CARBURETOR | Cheap Cycle Parts

See parts 41 and 42 in the diagram above. Looks like a #128 main and a #42 idle / slow jet. Not sure what the parts are at #43 and #44. Maybe somebody else will know.

Rick

 

[Goober]

Hi look the service manual for guidance. I spose if you’re above 5000 ft for a long time you could foul a plug or two. Yes there is a high alt jet.

 

[Texn]

Hi look the service manual for guidance. I spose if you’re above 5000 ft for a long time you could foul a plug or two. Yes there is a high alt jet.

So my manual lists the Main Jet to be #128S and the Slow jet as #42S.

Sorry, but I am still a little confused on what this parts diagram has and what I need.
https://www.cheapcycleparts.com/oemparts/a/hon/5053dd9ff870021c54bdcd7b/carburetor

parts 41 and 42 is likely where the issue lies. I guess I can call cheapcycleparts and see what they say.

 

[Texn]

Hello Again,

2005 Honda TRX350FM A CARBURETOR | Cheap Cycle Parts

See parts 41 and 42 in the diagram above. Looks like a #128 main and a #42 idle / slow jet. Not sure what the parts are at #43 and #44. Maybe somebody else will know.

Rick

thanks for the advice. Yeah I kind of got stuck at the same place as you on the jet issue. I saw the parts, but it doesnt say much about either option.

 

[misterclean59]

You will need the next sized smaller main jet. You may need the next smaller pilot jet. The fuel screw may or may not adjust the slow circuit enough. I'd replace it to be safe and go back with the stock if it runs too lean.

 

[Goober]

Please check the manual don’t think you need a slow jet resize. I only needed to change the main jet and kick the pilot jet back a little.
I usually run at 3200-4200 and occasionally run trail at 5000-6000. Good mix for me.

 

[Menard_LaPue]

IMO, 7500 feet is just a little below "high elevation". I wouldn't worry unless you have sustained travel of at least 9,000', or higher. At 12,000', certainly an issue. Just my opinion, but I have a lifetime of experience at high elevation.

 

[ybs.mike]

I know its old, but this will help those like me that just got a 350ES.

The link to DynoJet's jetting kit provided

Q108.001 2000~2006 Honda Rancher 350 2X4 & 4X4 Stage 1

ATV Jet Kit for 2000-2006 Honda Rancher 350

This Kit has a PDF with instructions for elevation jets and settings........
Everything you need to get it running right.
BTW, they consider high elevation anything above 6000'.
(Not saying thats correct or not, but they dont list any different settings above that.)

Q108.001 2000~2006 Honda Rancher 350 2X4 & 4X4 Stage 1

For mildly tuned machines using the stock airbox with stock or aftermarket filter.
May also be used with a good aftermarket exhaust system.

This is in the kit they sell, that I bought for my 8500' Elevation.
Parts List
1 Main Jet DJ112
1 Main Jet DJ114
1 Main Jet DJ116
1 Main Jet DJ118
1 Main Jet DJ120
1 Main Jet DJ122
1 Main Jet DJ124
1 Main Jet DJ126
1 Fuel Needle DNO767
1 Adjusting Washer DW0001
1 E-Clip DE000


STAGE ONE INSTRUCTIONS 1. Remove vacuum slide from carb. Remove stock needle & spacers, noting order of assembly (Fig. A). 2. Install Dynojet needle on groove# 3 from the top for applications below 6000 feet, groove #2 for above 6000 feet, using all stock spacers. Install the Dynojet washer above the E-clip. 3. Remove stock main jet and replace with Dynojet main provided. If using the stock exhaust use the DJ120 below 3000 feet, DJ116 from 3000 to 6000 feet and DJ112 above 6000 feet. If using an aftermarket exhaust with a high flow baffle use the DJ124 below 3000 feet, DJ120 from 3000 to 6000 feet and DJ116 above 6000 feet. Be sure that the jet you are changing is the main jet. 4. Locate the fuel mixture screw (Fig. B). Using a flat blade screwdriver, turn the mixture screw clockwise until it seats, then turn out 3-1/2 turns .


Link:

https://www.dynojet.com/amfile/file/download/file/1596/product/4539/

 

[ybs.mike]

I know its old, but this will help those like me that just got a 350ES.

The link to DynoJet's jetting kit provided

Q108.001 2000~2006 Honda Rancher 350 2X4 & 4X4 Stage 1

ATV Jet Kit for 2000-2006 Honda Rancher 350

This Kit has a PDF with instructions for elevation jets and settings........
Everything you need to get it running right.
BTW, they consider high elevation anything above 6000'.
(Not saying thats correct or not, but they dont list any different settings above that.)

Q108.001 2000~2006 Honda Rancher 350 2X4 & 4X4 Stage 1

For mildly tuned machines using the stock airbox with stock or aftermarket filter.
May also be used with a good aftermarket exhaust system.

This is in the kit they sell, that I bought for my 8500' Elevation.
Parts List
1 Main Jet DJ112
1 Main Jet DJ114
1 Main Jet DJ116
1 Main Jet DJ118
1 Main Jet DJ120
1 Main Jet DJ122
1 Main Jet DJ124
1 Main Jet DJ126
1 Fuel Needle DNO767
1 Adjusting Washer DW0001
1 E-Clip DE000


TAGE ONE INSTRUCTIONS 1. Remove vacuum slide from carb. Remove stock needle & spacers, noting order of assembly (Fig. A). 2. Install Dynojet needle on groove# 3 from the top for applications below 6000 feet, groove #2 for above 6000 feet, using all stock spacers. Install the Dynojet washer above the E-clip. 3. Remove stock main jet and replace with Dynojet main provided. If using the stock exhaust use the DJ120 below 3000 feet, DJ116 from 3000 to 6000 feet and DJ112 above 6000 feet. If using an aftermarket exhaust with a high flow baffle use the DJ124 below 3000 feet, DJ120 from 3000 to 6000 feet and DJ116 above 6000 feet. Be sure that the jet you are changing is the main jet. 4. Locate the fuel mixture screw (Fig. B). Using a flat blade screwdriver, turn the mixture screw clockwise until it seats, then turn out 3-1/2 turns .


Link:

https://www.dynojet.com/amfile/file/download/file/1596/product/4539/

And yes a 128 Main and 42 Slow Jet is stock.