anyone have any info like when, how much
how it performs

It's been discussed already. Do a search...there are pics too!

can't find it help me out here searched under
several things did not find much.
still wondering how much when and how much it helps.

help i have fallen and am to stupid to get up


02/yz250f 1/29/02 added atc 90 runs but not fast
02/yz250p
01/kx250
01/yz125
73/road toad
00/xr70

[ January 28, 2002: Message edited by: dynoman ]

[ January 29, 2002: Message edited by: dynoman ]

I searched for dubach air box pics and got the following link:

http://www.thumperta...=10&t=002359&p=

No one has tried one yet because they are not for sale yet. February I think.

I spoke with Gina Dubach the other day and she said that it should be ready early next month. They are expecting gains of 3-4 Hp. out of it and a weight loss of 1lb. It is not cheap, $499, I will assume we will get our TT 10% off of that.

Can you really get 3-4 hp from adding a new airbox? If this is the case.... I will definately be buying one. I need some more power and dont want to do anything to the motor and everything has been bought.

Sean

Why waste the money? I was able to put the air box, seat and side panels from a YZ125/250 on my 250F with very minimal modification. The air boot is a direct bolt on. It's much, much lighter than stock, easier to service and it flows a lot more air (I had to go fatter on the needle and main jet) The air box only cost me $62.00 US. SDG seat cost was $80.00 and the side panels were $45.00. I needed to cut 4mm off of the pipe mount at the frame to pull it away from the air box. But that was as hard as the mod got. Looks cool too!

Godfather

3-4 hp gain i very much doubt it. but we will see.
how much more does this Dr d pipe give?

500 is a bit steep but if it gives three to four Hp more then that is worth it. as that kind of gain is phenominal.

but i am interested though on this yz 2 stroke add on.what do u mean cut the pipe mount. did u have to then weld it back in place or what? and what years yz was this from?

how much faster is ur bike with it?

could u give an estimated gain?

It's kind of hard to estimate the gain because I don't have a dyno. I did the mod because I had a 290kit in my bike and that really up'd the volume of air being drawn through the carb/air filter/airbox system. With the stock set up, it felt like the motor was struggling on the top end. The 2-stroke airbox made the motor feel like it rev'd faster and farther... And the set up is much lighter. As far as the pipe mod goes, I had to take a hack saw and cut about 4mm off of the welded on stud on the mid pipe. Basically, cut enough off to pull the mid pipe up next to the frame tubes. I even went and far as doing a little metal forming of the mid pipe where it would touch the frame just to get a little clearence. It is a tight fit but it works. I forgot to mention that I had to pull the seat cover back on the seat where it met up with the lower part of the tank and do a little trimming of the seat base to get a custom fit there. All-in-all, it was easy to do. The side panels fit well with my PC T4 pipe and with my WB e-series. I also did it for my buddy's 426 with an e-series pipe. The mod seemed to be easier to do on the 426.

Godfather

Quote

how about some pics?

GODFATHER,Thanks alot! Now you have my brain thinking.Just when I was looking to buy a C/F AB.If the deal falls through this could be an option.Might be worth a chance,whats 60 bucks nowadays.Anyone else ever heard of this? Did the 125/250 ab go on easy you say? Maybe I could borrow one for a day,need to call a sucker,er,I mean friend!Somebody has to do this and let us know,the world [our own little world]needs to know!Damn,this is gonna drive me nuts!

What year is your 250F and what year the new parts ?

Don't forget the guy on ebay who is selling a conversion kit like this. He made a plastic airbox to accept the two stroke side panels.

Scott Boyd is the guy selling the air box for the 250F that accepts 2-stroke number plates. I emailed him recently to see if he was still offering them and here is the response:

Yes I am still selling the airboxes!
They are $119 without the sidepanels. They are 13 ounces lighter than the stocker.
I haven't done anything else with the seat. Most everyone I talk to (and myself) just use the stock seat...the gap isn't that noticeable and the tradeoffs are worth it.

When I inquired about how much weight is saved from the 2-stroke side panels, here was the response:

They save about 2-3 ounces. Most of the weight reduction is from the box.

His email address is: letsmoto@earthlink.net

The thing mentioned above about the seat gap was the 250F seat doesn't match exactly with the 2-stroke number plates. He mentioned that you could put a 2-stroke seat on, but it is not as flat as the 250F seat.

I have an 01 250 f.So all you need is the airbox and 2stroke side pnls?Does he say anything about performance gains at all?Let us know or should we contact him to ask?Gotta ck this out.THANX

---------
RIDE TILL IT HURTS AND THEN SOME

Mike Tolle from MT Racing (the Vortex Ignition importer) said that the Euro race teams are running the YZ250 (2T) airbox like GodFather did. He didn't say what all was required to do it though. He said it flowed like 13 CFM more than the 250F box.

GodFather

Why did you have to change the seat? If you are using the same subframe I haven't grasped the seat change yet? Also, did you have to change the side panels or did you do it for weight savings? It seems like the pipe would melt the 2T panels.

My big question is if it's worth it if you don't spend all day on the rev limiter? Does it improve the throttle response and low/mid power enough to make it worth the investment?

I managed to ask 6 new questions.
Thanks

YZ Abuser,

The guy selling the ebay airbox said the seat number plate juncture doesn't line up perfectly. If you want a perfect fit, then you buy the 250 2-stroke seat. The problem then is that seat has more of a dip in it (isn't as flat). Sounds like the ultimate would be custom seat foam on a 250 2-stroke seat base.

I have been out for a while, so I will try to answer as much as possible. I used the 2-stroke seat because I am kind of particular about how my bike goes together. The YZF seat works but it looks kind of cheezy on the 2-stroke side panels and there is a larger gap between the yzf seat and the 2-stroke airbox. I also did not care for the hard flat yzf seat. My SDG YZ seat seemed to have thicker foam and it just felt better to me. To use the YZ seat, you need to do some minor trimming on the seat base where it meets the lower part of the tank and you also need to cut the slot about 1/4' deaper at the top of the seat where it hooks to the tank. You have to use the 2-stroke side panels because they are part of the 2-stroke airbox design. I took a hair dryer to the exhaust side panel to kind of form in around the pipe; But it did not really need much. I am kind of a perfectionist. The 2-stroke air box bolts directly onto the yzf subframe; No mod required. The YZF snorkle bolts right into the 2-stroke airbox with no mod required. The whole set up lines right onto the carb just like it came from the factory that way. Then I cut the 4mm (or so) off of the mounting stud on the exhaust mid-pipe. The mid pipe needs to be pulled as close as possible to the frame tubes to allow clearence at the airbox. I got about 1/4" clearence from the mid-pipe to the air box and never had a melting problem. I also trimmed about 2mm off of the muffler mount where it bolted onto the subframe to add just a little more clearence for the side panel. I know it sounds like a lot of detail but it was really not a hard mod to do. It really looked factory when I was done. Sorry that I have not posted pic's yet. I don't have a digital camera, so I will have to borrow one. I would offer my phone number to anyone that had more questions but I'm afraid that I would never get off the phone.

Godfather

Godfather: Do you have a 01 or 02 YZF ? Do you think (if you have a 01 YZF and 01 YZ parts) it could be done on a 02 YZF with the new 02 YZ air box, side panels and seat ? with the added performance and lower weight, the bike would look ultra trick with the new 02 airbox/side panels combo !

I had a '01 yz250f. and I used '00 yz parts because I wanted the black airbox. All the yz's from about '96 and up to '01 are the same. All these parts should fit on the '02 YZF also. I am starting to see these mods at my local tracks. My buddy's tell me that I started a trend.

Godfather