I'm planning out my mods atm, and need some advice on a few things.

So far, the only thing i've done is toss the airbox cover. Sounds allot nicer, but I haven't noticed any performance gain, and it seems like the power band really gets flat once she hits around 7000-8000 RPMs. I never really noticed this prior, so i'm wondering if this is a side effect of how lean the mod made the bike, or if it's just a characteristic of the bike that I hadn't noticed before.

In terms of the actual mods though, what i'd like to do is purchase an exhaust kit (most likely the Big Gun, since i'm sure the ceramic header will help fight the salt air where I live), and then either a TM33 pumper, or just a dyno jet kit.

That's my first problem, deciding betwen the TM33 pumper and the dyno jet kit. Is the TM33 really worth the 300 dollars? Is the change in responsiveness that great? Is the cleanup in the powerband worth the 300 dollars? What sort of hit to fuel economy can I expect?

When we hit the trails, it's almost allways with my uncle and at least his son, and the frequency of the trips has really been dwindling. I can safely say that a good 70-80 percent of my riding will PROBABLY end up being street, but it all depends on how this comming year goes in terms of schedule.

 

i asked similar questions and everyone on here was really helpful - all i did was Big Gun ,K&N and jet kit will go in saturday or sunday...you can check out my thread for info "pumper carb vs. stock carb"

 

I could have sworn that I scoured the entire board, I can't believe I missed it []

Oh well, another Q.

Should I be running some sort of airbox lid when I hit the muddy stuff? I figured it can't be that bad since my uncles son runs his two stroke YZ without an airbox lid.

 

well i just found my 2001 300EX tail pipe so i'm keeping mine on, i'll loose if i don't haha. but its up to you, you're riding trails against a 2 stroke, i dont know how much more power you are gonna get with the lid off...i trail ride with 2 klr 650s 2 drz 650s a dr400 and a klr250 when the 7 of us go out me and my younger brother with the klr250 always have the most fun, its funny watching those fat 650's wipe out in the sugar sand...anyway i'm rambling , start a post "airbox lid on or off" and list your mods everyone that has responded to me has been helpful

 

the airbox lid faces up anyways, its not gonna hurt it, you plan on sinking your bike that far? i remember reading on this forum that u might have to tinker with the jetting if you do keep it off

 

Oh, my old bike's gone through some serious hell. I remember me, my uncle, and his son were maybe 10-20 miles into a trail when a flash flood hit, and what used to be a fairly solid hill turned into a giant waterfall of mud and god knows what. We had to tie each bike up to ropes, and have two guys pull at the top of the hill while one guy on the bottom pushed.

The water was so high that we didn't bother unzipping to take a **** :|

But I suppose that was an unusual day. I've lost my bike in some fairly deep water crossings, effectively submerging the bike for a good 2 or 3 seconds, but I think i've matured enough as a rider to tackle the previously hairy crossings.

I'm still wondering though if the airbox lid removal would have caused that flatspot. I swear, it was never there before. I remember being able to wring the throttle dry and the bike just kept going and going and going and going. Now, at about 8k revs, the bike doesn't seem to go any faster. It doesn't slow down, but the acceleration and power completely disapear.

 

hahaha peeing your pants is the coolest (billy madison),thatsprobly what did it,put the lid back on and see if it goes away, it should, if it does then put on your after market air filter and see how it feels with the lid on, most of what i read on here people like the uni filter

 

You really need to put the richer jets in to get any performance gains with the airbox lid off - plus without a high performance exhaust/slip-on (or at the least the stock muffler drilled) - too much back pressure (no place for all that extra air you're taking in to go). You're also causing the engine to run hot and very lean with just the airbox lid off.

 

I guess i'll pop the lid back on then. I DID notice an increase in temperature, yet wasn't sure if it was just because the ambient around here increased a bit in the past few days.

Just the other day I was riding under 20mph, and I had to kick my left leg out because the heat was getting very uncomfortable.

Sad though, I really do enjoy that thicker sound with the airbox lid removed.

Is there anything I can do for now to even out the jetting, without rejetting the entire carb?

 

You will end up destroying your motor if you have the lid off without rejetting due to the motor running very lean. It runs lean stock but with the lid off it will be lean to the point of the excessive heat you have already noticed cooking the piston and rings and maybe the valves too. Of course any damage you do will NOT be covered under warrenty.

Cheers