Page 1 of 1

GT250A airbox, road trial pending

Posted: Sat Aug 31, 2019 5:03 am
by daxman
Hi All

The 'A' is getting close to a road trial :shock: .Having had to helicoil the oil pump inlet thread and order a m/c rebuild kit (brake was locking on with rebuilt calper) I concentrated on re-fiting the airbox, BUT inspite of buying a new box-carb rubber at no small expense it's proving a SOB to refit. Thinking of abandoning and using cone or foam types instead. The bike is already very unoriginal (e.g. GN250 seat, GSX 250 rear mudguad) so I don't care much about looks but function is important. Would it be OK? I noticed that running with open carbs it won't rev. until I place a hand over the mouths so I realise some restriction is needed.

Cheers

Re: GT250A airbox, road trial pending

Posted: Sat Aug 31, 2019 11:14 am
by dollydog
aha, somebody else that's found out what a barsteward those carb to airbox rubbers are to fit. it must be the worst job ever on a gt250 :D if you're going to fit airfilters, i'd go with the foam type, not the k&n type with the solid ends. just something i've learned from experience and other people over the years :D
cheers, dd.

Re: GT250A airbox, road trial pending

Posted: Sat Aug 31, 2019 11:49 am
by daxman
HI DD

Thanks - yes its like juggling, trying to keep three balls in the air at once (or three things clipped on). I'm going to have another try with the battery box off tomorrow, then its pod. Although i had another thought to use the rubber but clamp a bit of of filter foam over the oval - not very rain resistant though..

Re: GT250A airbox, road trial pending

Posted: Sat Aug 31, 2019 1:00 pm
by sportston
Try a bowl of boiling hot water straight from the kettle. It softens the rubber up and makes it easier to stretch it onto the airbox. Its worth it to avoid the hassle of trying to tune the carbs to pod filters. But as already said if you absolutely must use pods, get the foam type, not cone type

Re: GT250A airbox, road trial pending

Posted: Sun Sep 01, 2019 3:24 am
by dollydog
easiest way to do this horrible job, i found putting the rubber on the airbox first is a must. the airbox is obviously removed :D then, once the large jubilee type clip is tight, so the rubber can't pop off, struggle the airbox c/w rubber roughly into position. loosely fit the top bolt, smear of grease round the carbs and with a bit of luck - works for me - with a push from behind the airbox the rubber should pop on. trying to fit all 3 holes at once is basically impossible and a new rubber makes ALL the difference. good luck :D
cheers, dd.

Re: GT250A airbox, road trial pending

Posted: Sun Sep 01, 2019 5:50 am
by jabcb
I use a pick with a 90 degree tip to help get the boot lined up & started.
https://www.amazon.com/Craftsman-Hook-P ... B001OIMXYI

Start with the boot attached to the airbox, but the airbox not bolted to the bike.
Lightly push the boot against the carb & run the pick around the circumference to line the boot up & get it started. Then push & its on without too much trouble.

Re: GT250A airbox, road trial pending

Posted: Sun Sep 01, 2019 2:51 pm
by dollydog
pretty much the same jab, but if the top bolt is loosely fitted then the airbox will swing at the right angle to go on. another thing i did was just before i fitted the rubber to the airbox, was push the rubber over one of the carbs, then off again and repeat for the other side. a smear of grease really helps as well. still one of the worst jobs on a gt250. even rebuilding the left hand switches with cold hands is a doddle to fitting those bloody carb rubbers :D
cheers, dd.

Re: GT250A airbox, road trial pending

Posted: Sun Sep 01, 2019 4:26 pm
by daxman
Thanks again.. now I need to find some narrow-band hose clips for the carb end. :roll: Looking at T350 types which i think are 8mm band.

Re: GT250A airbox, road trial pending

Posted: Mon Sep 02, 2019 6:01 am
by dollydog
hi dax, i just measured the band on my spare rubber and it's 7mm wide :D unfortunately no longer available from suzuki.
cheers, dd.

Re: GT250A airbox, road trial pending

Posted: Mon Sep 02, 2019 7:59 am
by markush
do it Yourself!
made of 0.5mm (stainless) steel sheet.
Eigenbau_Schelle.jpg

Re: GT250A airbox, road trial pending

Posted: Mon Sep 02, 2019 9:53 am
by jabcb
The clamps are available from Suzuki in the US, and from CMS in the Netherlands.
https://www.cmsnl.com/suzuki-gt250-1973 ... W06wi2ZPFw

Re: GT250A airbox, road trial pending

Posted: Thu Sep 05, 2019 1:55 pm
by sportston
Why not use a jubilee clip? They come in various sizes of diameter and width. I have stainless ones fitted to my bike. They work fine.

Re: GT250A airbox, road trial pending

Posted: Thu Sep 05, 2019 2:26 pm
by dollydog
i've used these before. they aren't brilliant as they seem to strip when you've used them a few times, but if you're only tightening it up once they should be ok :D 8mm, but they do fit under the lip on the rubber - i just tried a length of mine :D
cheers, dd.

https://www.ebay.co.uk/itm/Hose-Clamp-C ... SwNCtdJxEp" onclick="window.open(this.href);return false;

Re: GT250A airbox, road trial pending

Posted: Fri Sep 06, 2019 5:19 pm
by daxman
Hi - infact I just orderd soem 8mm like that but 'ready made'. Fingers crossed.. Now having another issue with teh m/c.. tut.

Ps Thanks all :wink:

Re: GT250A airbox, road trial pending - Update

Posted: Mon Sep 09, 2019 4:23 am
by daxman
Update - after an a hour or so of swearing, pushing, shoe-horning and disassembling I got the b*gger on :up: - had to remove battery box and pump cover and loosen all other clamps though. Subsequently getting the pump cover back on was another challenge :?

Now I was also looking at the filter itself. I made some new foam 'sleeves' but inside the filter 'frame' it is also stuffed with some white fluffy fibres - is this normal?

Cheers