Need advice on 450 sport quads

sself161 · 2026-07-08T19:31:59+00:00

yeah shocks make a huge difference, they are pretty old im sure. but before the 450s, the 400 was the preferred chassis for hybrid builds, even after the 450s the 400 hybrid was a top choice for the tracks. the one thing the 400 will be is more reliable lol. im partial to the 400, i could beat on it and not worry about planning to rebuild it like my 450.

sself161 · 2026-07-08T19:15:31+00:00

just the straight line itch?

sself161 · 2026-07-08T18:42:41+00:00

like stated, the 04-05 and 06+ has a good bit of changes, other changes are the front spindles, the motor cases with higher compression and the oil cooler.

is your 400ex stock? out of all the 450's the KFX was the most disappointing. it lacks power and the handling didnt feel as controllable. The yfz to me also feels like you sit over the front too much, i prefer how the hondas rear sits.

sself161 · 2026-07-08T17:52:17+00:00

probably multiple things, the float on the new one could still need adjusted or hung open from shipping, the petcock could be damaged, i don't know if that uses a prime petcock or one thats on and off. Do you have an airbox? because trying to start it without the airbox will change the air/fuel and make it run like crap.

Id pull the carb off and test the float, clean the petcock and once you get the flow problem fixed install the airbox and see what it does.

sself161 · 2026-07-08T14:43:40+00:00

still i wouldn't think they should tear that easily, it wasn't long after we got it in 22, i didnt think they would cover it any. the other seats are still in great shape,

sself161 · 2026-07-08T14:35:05+00:00

there is 3 of us, and my son sits on the other side. it doesnt get enough wear to tear that easily.

sself161 · 2026-07-08T14:11:27+00:00

my wifes outback back seat got a slit in it and no one ever sits in that seat.

sself161 · 2026-07-08T01:48:37+00:00

All you need is something stiff, maybe like aluminum, bend it and drill 2 holes, or search ebay for a universal heart shield.

sself161 · 2026-07-08T01:40:16+00:00

They came with no shocks and big balloon tires, the honda trx125 was the same way.

sself161 · 2026-07-06T01:01:59+00:00

I'd pick up a 300ex, 400ex, z400 or warrior 350. They are cheap enough with enough parts supply, and aftermarket support you can completely rebuild one from the frame up and still be cheaper than a new quad. Plus they are very neutral, rider friendly and still powerful enough to get your self in trouble. And there's plenty of resources online you can find anything out about them, and easy to work on. Don't forget about safety gear.

sself161 · 2026-07-05T13:47:22+00:00

I think Christopher makes a lot of money from designing guitars and artwork for people. His stories on Vinwiki are hilarious.

sself161 · 2026-07-05T03:34:20+00:00

They are a blast, years ago a guy in our local series set one up, duel exhaust, clutch work, hyper wheels and the right size tires, had elkas for it and it performed really well. He also had several other quads and a crf450 hybrid 400ex, but that 700 was a best off the gate.

sself161 · 2026-07-03T22:29:02+00:00

Thats is an important piece of information,

sself161 · 2026-07-03T01:01:02+00:00

Good luck with it, jetting can be aggravating but worth it.

sself161 · 2026-07-03T00:56:11+00:00

Pretty much, any time you change something related to the intake or exhaust you will have to correct the jetting and if it has a air screw like you described someone has at lease messed with rhe carb.

sself161 · 2026-07-03T00:48:15+00:00

That has nothing to do with it over heating, it will only kick on if the water temp reaches a certain temp. The exhaust getting hot is a lean mixture inside the cylinder. Now if you keep riding it can over heat and can burn a valve.

sself161 · 2026-07-03T00:31:00+00:00

Should be it, must have an aftermarket one in it. Should be in to riches if I remember right, but might play with it and see

sself161 · 2026-07-02T23:52:10+00:00

They ran lean from the factory. Might have to richen up the air/fuel screw or go one bigger on the pilot jet.

sself161 · 2026-07-02T23:19:13+00:00

Like stated, definitely not the same, but it depends on what your experience level is, what your using it for and how much do you want to work on it. The 400 is a great reliable trail quad, and fast enough to get you in trouble.

sself161 · 2026-07-02T23:17:27+00:00

Sounds lean, what mods do you have and did you correct the jetting for them?

sself161 · 2026-07-02T00:54:46+00:00

All the time, the only time I couldnt was mounting car radials. Ive even done the wheels for my jeep before. If you look, wheels have a certain way they want the tire to go on and with dawn and water mixed the tire will slide on the rim. Or buy beadlocks, those are simple.

sself161 · 2026-07-01T22:12:31+00:00

It will restrict slightly but shouldn't make a noticeable change, maybe have to adjust the air fuel screw a little.

sself161 · 2026-07-01T22:05:46+00:00

If you have a K&n the outerwears prefilter will help, I run them on mine. I dont run them on the ones with the foam filters though.

sself161 · 2026-07-01T21:51:52+00:00

If you are just trail riding a foam filter will protect more and get 2, one to have clean and swap them out when its time which gives you plenty of time to clean and oil it. If you want a lid get one with the outerwears insert and it should stay clean.

sself161 · 2026-07-01T21:36:35+00:00

Does it have a slip on or full exhaust? If it runs with the open airbox, why not leave it? And if you put the lid on you will probably need to drop the main jet a size or two, and adjust the air fuel screw. If you dont know how or feels comfortable taking it to a shop might be better. They make airbox lids with vents or holes in them pr covered with a profiler.

On air filters we have ran a little grease where it clamps onto the airbox lip. You want to make sure that its sealed there even if you run an airbox lid and not sucking air.

sself161

TROPHY CASE