GPX 250 airbox installation

[Martin]

Hey guys, im fixing up a 1989 gpx 250 and im having a few problems (im new to bikes)
the bike i bought didn't come with anything to restrain the battery, it was sitting on the rear wheel mudguard plastic...thing, and the mechanic i went to stipulated that this was unroadworthy. so i got a battery holder and airbox (one unit) from a wreckers and it dosnt fit. at all. its too wide. the wreckers have painted '07 gpx 250 on it so im assuming thats the problem, i know the bike design has been going for ages but...
well that really isnt the problem, the problem, more of a question, is that there was no airbox on at all right? all that was on were two pod like air filters straight onto the intake for the carby. now i though this would allow more air into the engine than this airbox would, so would what the previous owner have done be a performance modification? if so would i just be able to mount a strap or something to hold the battery down?

does that all make sence?

[MadKaw]

Have you got a pic..

We just rebuilt a zzr250 (very similar bike) for my wife and getting the airbox out was impossible, so we didn't. According to the manual, you have to remove the subframe.
So if you sre trying to fit it from the top with the tail still on, this may be why you think it doesn't fit. Not sure, just a guess..

[Daisy]

Its been a while since I did mine, but if I remember correctly you can get the airbox in and out if you split it and fit one half at a time. I do remember that it was a pain in the arse. The battery just has a rubber strap across it.

[Martin]

yeah ive undone the screws and split it in two, but the problem still is its a bit too long (or deep) in the base, it clashes with the idle adjuster and i cant fit the carby intakes to the box. its a real see you next tuesday of a job if i have the right box. should i even bother with it? or should i just leave the air filters that was on it on, two foam pod filters (ill take a pic in the morning cuz its too dark and cold out now) and just fix a strap to the battery?

[Martin]

update with pix

[robracer]

Why would someone do that?

[frog]

Because THEY couldnt get the airbox in either
I think you have to go in through the front, ie pull the carbies out, put the box in (I think the crankcase breather has to come off too?) then reinstall carbs. Only ever did it on exes ZZR250 but.

[Martin]

i didnt really want to start fiddling with the carby. lots of little parts to go wrong on me

[frog]

Nah mate pull them out as a whole. Just undo the clamps on the inlet manifolds. Piece of piss, mind you I HAVE been wrong before..... lots

[Martin]

done it!
didnt need to get the carby off

to anyone who needs to take out the airbox or install an airbox:

i did everything with the rear wheel (replacing chain and sprockets anyway), seat, fuel tank, side fairings and rear fairing off - rear section completely naked and the bike on the center stand
unbolt the coolant reservoir tank, push it out the way, and the little electronics box THING next to it. just get em out the way.
unbolt the rear break fluid reservoir tank (little thing) and the fuse box next to it. push them out the way.

this will give you the clearance you need to slide the airbox out

now the mudguard needs to come off. it has two bolts on the top, about midway along the mudguard, two bolts in a nice and awkward to reach place low down on the inside (probably covered in dirt) and a bolt or two on the left. the only way to reach the two bolts low down on the inside is with an extender on your socket wrench.
The spring for the seat lock has to be removed (ply it out of place).
There are also two bolts in the bottom of the battery tray.

when its free (if i haven't forgotten any bolts) with a bit of shimmying it should slide out backwards and down. i imagine this to be a bastard of a job with the rear wheel still on.

with the mudguard out of the way, on the airbox, where the airbox meets the carby, push the two springs back (towards the airbox) so the hoses are free of the carby. (the hoses have two rims along it for the springs to sit on, the rim closest to the airbox is the 'release' rim).
The airbox should now be removable with some shimmying.

if your taking the airbox apart, it splits in two halves, but for gods sake remember to keep the carby intakes, the inside of the airbox and the filters clean. also don't forget to put the filters back in the airbox BEFORE you put the two halves together (yeah i put everything back, wrestled the airbox back into place and realised id left the filters out).

getting the airbox in gets easier each time you do it. slide it up and from the back. get the hoses located onto the carby intakes first, with a bit of shoving and tapping from the rear they seem to line up quite easily by themselves. i did have to push the carby up a little as i did this so they would meet.
Push the springs on the hoses back onto the front rim (the rim furthest from the airbox, closest to the carby is clamped). Dont fiddle with the airbox now. its only being held by the hoses. i did that too. it slips out of place and you have to do it again.

put everything back together. rear mudguard, coolant tank, break tank, electronics. it should all fit snug.

[the kid]

Good post Matey . Have wrestled with a GPX airbox before and it was a nightmare . Will reread your post before I attempt it again .