Tech Review - UNI Filter

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Sidney

Well-Known Member
Joined
Mar 15, 2007
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Location
Adelaide, SA
PRODUCT: UNI Filter
PRICE: $25-$30
WHERE TO BUY: Basically most pitbike shops but it could sometimes be hard to find the right size, or you can get them online.


Well, if you want to make a noticeable amount of faster throttle response a UNI air filter is definitely a MUST HAVE. I didn't think putting one on would make so much of a difference. Compared to the stock airbox which is restrictive as hell, this definately makes your Honda CRF50F perform A LOT better. It also makes the engine sound better which is a bonus :)

It will take you about 5 minutes to install your UNI.

I will guide you through the steps (I have no pics sorry)

1. Remove your seat and plastics
2. Remove your fuel tank (The reason for this is that the nut that holds the Earth wire and the top of the airbox in place is inline with the fuel tap so the nut is difficult to undo)
3. Take off the nut that holds the top of the airbox to the frame. You can put it straight back on because the UNI Filter doesn't use that bracket (you still have to put it back on for the Earth Wire.)
4. Undo the Phillips head screw that closes the hose clamp that holds the airbox in place.

OK so you should have your airbox off now and you simply slide on the UNI Filter and do up the screw on the hose clamp and you are done!

You don't need to adjust your carby in any way.

As soon as you kick over your 50 you will notice a difference in throttle response!

WHAT I LIKED

Performance: I love the way my bike revs up a lot faster and it has a small gain in power compared to the restrictive airbox.

Looks: I simply think a foam filter looks better than an airbox haha. The UNI airfilters come in Red and Green in colour. You can also buy a straight one or a 30 degree angle bent one. I am currently running a green angled UNI.

FIT: It is basically a "bolt on" modification which a massive difference in performance.


WHAT I DIDN'T LIKE:

Getting the old stock airbox off hahaha. When you have a UNI you don't need to get the tank off which makes life easier. :)

Comments:

Seriously consider getting one of these as a first modification for your CRF50F because they make a big difference for the little money.

MY RATING - 9/10

Q&A

Q. I have just put a UNI on my CRF and now it's not starting, what do I do?

A. Check that you put the nut back on where the airbox was held onto the frame, the earth wire has to be on firm.

Q. What size UNI fits my stock CRF50F?

A. 29mm,30mm,31mm (maybe a couple more but these will be your average sizes)


Well here are some pics of my bike with the UNI filter.

Image002.jpg


might be hard to see in this pic \/
Image001.jpg


cheers guys
 
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it will make some differnce to your power but it all depends whats on there atm... as the crf50s have a restrictive airbox it makes a huge differnce to open it up and let more air in!

great man.. just simply for the look and the performance i would always run one, just knowing that WHEN its clean and not clogged up with dust, dirt, bush and other stuff it will not restrictive anything and run to peak performance!!

great review man i love the set out, very easy to read (everyone should take a leaf out of sid's book on this one) =)

good work bro! =D
 
great review, but will it make much of a difference on a 125 or 140?

Not very much because they already have a foam airfilter but I was comparing my UNI to the stock CRF50 airbox, which WAS a huge difference.
(everyone should take a leaf out of sid's book on this one) =)

I loosely base mine on unit mx's review lol but you can use my layout if you want.
 
Foam are ghey for the simple fact that u goto throw them out.... UNI's pay for them selves after a while. And they look ubes
 
good review
don't forget that most uni filters come un oiled and you have to oil them before use. Once you know how to clean and reoil them they are great and will pay for themselves over a standard replaceable filter.

Also on most pitbikes the old filter is very simple to remove, undo hose clamp and pull it off.

To help with correct sizing aswel you should either take your old filter into the shop with you or simply remove the filter and measure the inside diameter of the flange that bolts onto the carbie.
 
What are you talking about mate... Ive had a UNI for about a week so why would I ask where to buy one yesterday?


link please
 
hmmm..i'm after a uni filter in 50mm diameter atm. But uniflow are on holiday till the 7th. Anyone know where i could grab one online or something?
 
Guys pics have been added. Should I make a tutorial on how to clean your UNI?

cheers
 
alright I'll do it when mine is dirty again because I cleaned it last night haha
 
good review sid. I've had mine for almost a year untill the gator on the boot seal ripped open and now the filter is rooted but still how many external filters last 12 months? (my china stocko lasted a 3 rides haha) half my fault for doing it the hose clamp up a little tight.
Tip for the kids
Put a cable tie around the filter gator where the flange starts so that the hose clamp does not slide down the filter and pinch the gator and rip it.

Also clean your filter in oam washing detergent in a ice cream container , it works better than no toil filter treatment.Dont oil your filter in regular tin can air filter oil as its way to thick and any trace of dust near the bike it attracks and sticks to, instead use the spray on filter treatment or 3 in 1 oil.
 
Hi guys,

Sorry if my question sound dumb. I bought my motovert expert '07 2nd hand and I'm really new to pitbikes. anyone here knows what size UNIfilter should I buy for my stock Motovert?

I believe my carby's a mikuni 25mm...
 
if u want to get a new uni airfilter just take ur old on off and take it with you to the shop and they will get you the one that fits
ur carby will be 26mm im pretty sure cuase thats the same one as mine
 
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