Best pipe for trail riding.
 

I have an 05 250ec, totally standard. Would like a bit more bottom end. The bike is used for tight techincial trail riding. Which pipe would give the strongest bottom end, top end not important. Also has anyone fitted a flywheel weight or one of those aftermarket powervalve covers.
Any advice appreciated, Thanks Paul.

FMF Gnarly pipe focuses on increasing the lower RPM horsepower and torque to get you out of the toughest terrain. When looking to add 4-stroke tractor like torque to your 2-stroke and you need a pipe to withstand the harsh elements, this is the pipe for you.

Nickel plating is an FMF trademark and has been ‘copied’ by everyone making it the most imitated expansion chamber in the world.
Super strong18 gauge steel construction makes it GNARLY

www.fmfracing.com/Mode/Category/51

I prefer the mesico power delivery for off-road.. but the thin wall makes it a consumable part. The GG stamped pipes are copies of this I believe,, and somewhere on here was a pipe test.. do a search it should come up.. the fmf gnarly and fatty for the GG are the same pipe,, just thicker metal on the gnarly.. so a little more mx like.. I took the fmf off my 03 and went to a messico and armor plated it as best I could.. I ride rocks.. so I needed grunt.. the 03 had the worst bottom end and the messico pipe, boysen cf reeds(pre v-force bike) and an 01 xc cdi gave that bike killer bottom..
In fact I have a messico now for my 97 and an fmf too,, but I like the messico.. just working on a silencer to fit the pipe.. The motowest pipe was the best pipe for low end but they didn't make many.. I have a proto-type that is badly crushed and was repaired over a dozen times.. I'm thinking about fixing that pipe one last time.. need to borrow a tig welder and get some 18G sheet metal to do it tho..

The GG pipe originally on my kids bike was excellent for lazy trail riding. When he smashed it we put on a Gnarly. The FMF comes on stronger at low end. I think for easy trail riding the GG pipe was much better, I think they are the same or similar to the Messico.

To smooth the power and make it easier to use, you can try a CCK needle
in the carb- so easy and cheap to try. Eliminates the 1/4 -3/8 throttle
mini-hit.

Also, I can personally recommend the RB Designs head mod, VERY noticible
low end improvement. :eek:

A 10 or 12 oz. flywheel was tried and I really liked it, too.


Jeff

-01 300 XC with head mod, big ignition, LTR power valve cover
(going to try a 35mm carb- we'll keep you posted, as I want
what you want, too)

My personal favorite for trail riding is the stock GG pipe (which is like the Doma).

I have used the FMF, Doma and stock GG pipes. The FMF pipe signs off very early. The Doma on my '01 XC300 and the stock GG pipe on my '06 EC300 are nearly identical. The stock GG pipe and Doma are much more linear, smoother and have much more top end power than the FMF.

My real world dyno is a hill. On a steep dirt hill, my '01 XC300 with the FMF was only able to pull 3rd gear at a moderately high RPM. When I put on the Doma pipe, I could pull 4th gear screaming at a much higher RPM than with the FMF pipe in 3rd gear. It was a huge difference.

The Doma & stock GG pipe are much better than the FMF Gnarly for my technical trail riding.

If you really want a strong low end boost and better fuel mileage, then get the RB Designs head mod.

I think you're going the right direction, but I'd try the less expensive things before going to the pipe. Cheapest way to get what you want would be to do the $75 RB Designs head mod. I realize it's half a world away, but if you have a period of the year where you have down time, I'd consider it. This combined with jetting will yield the most cost effective results. The LTR powervalve cover, or anything like it is also a worth while mod. It improves the low end response, is relatively inexpensive, and very easy to install.

A flywheel is a really good idea for what you are describing. I'd say get the biggest one they make. If there's a 16 oz available, get it. It's truly amazing the effect a flywheel has for keeping an engine chugging. A 16 oz flywheel will make it almost impossible to stall, and actually improve traction over difficult terrain.

All of these mods are inexpensive, and effective. If you really want a new expansion chamber, then that's one thing, but if you're after low rpm performance, one or a combination of the items listed above should make you pretty happy. The easiest two would be the flywheel weight and the powervalve cover, I'd do them both first and see where that takes you.

Is there room to add a flywheel weight to a '03 ec250?

If you have a DE/XC250 then adding a flywheel weight is a great idea for trail riding.

If you have the EC250 it has a good flywheel - even better than adding a flywheel weight to the DE/XC250.