Twin air filters

[sprtrx300ex]

How good are these?
How do they compare to stock and K&N?
Do i need to rejet my 300 for just the filter?

[White_Knuckles]

Twin and UNI are quality filters and about the same deal really. If your stock has had more than 12 solvent cleanings it's time for a new one. The K&N thing has a lot of hype with airflow vs. fine particle blocking properties. The cost vs. performance difference is marginal. If you ride desert sand the K&N by itself is fine (sand = large particle). If you ride dry dusty trails add an outerware sleeve, now you have spent $55 for a filter.

If you are trying to benifit from the increased airflow of K&N you must punch holes in your airbox lid or remove the lid totally and re-jet the carb to a larger main jet. This mod can be done with foam or the K&N. If you keep the lid stock, the benifit of any new filter for increased performance is not going to happen - no change. The UNI or Twin is cheaper than a replacement Honda filter. For the additional expense of a K&N, I don't think the airflow deal is really "feelable" and personally trust oiled foam more.

[cals400ex]

i have a twin air and it seems pretty durable. there was no performance from it though. i now run without a lid and jetted the bike and that helped for performance. if i had to do it again, i would get a uni.

[sprtrx300ex]

OK then, I guess i'll get a UNI filter.
If i put just a UNI filter on and leave the airbox lid on, do i need to rejet?

[White_Knuckles]

Originally posted by sprtrx300ex
OK then, I guess i'll get a UNI filter.
If i put just a UNI filter on and leave the airbox lid on, do i need to rejet?

No need to rejet, but you're missing the best low buck mod known to 4-strokes. I installed a UNI filter, added (4) 1" UNI pop-in filters (inserted into airbox lid), a Pro Circuit T-4 slip-on pipe and 3 dealer main jets (for ranging) all for $250 total.

That bugger jumped up and hauled, remarkable difference. You can do it in steps but the jets may need to be adjusted per step increments.

[cals400ex]

i know the uni vents come in a 6 pack. they don't let too much dust in the air box either. for $10 i thought it was worth a shot. with just an airfilter, you won't need to rejet.

[northeast400]

I have both a uni and twin air, I like the uni better because the twin air uses the stock filter cage and in is very tight going on and off, the uni is one piece and does not use the stock cage.