GT250A airbox, road trial pending

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daxman
To the on ramp
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Suzuki 2-Strokes: A100 GT250 & 4t Yams!
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GT250A airbox, road trial pending

Post 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
dollydog
Yeah Man, the Interstate
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Suzuki 2-Strokes: several gt250 ramairs

Re: GT250A airbox, road trial pending

Post 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.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
daxman
To the on ramp
Posts: 348
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Suzuki 2-Strokes: A100 GT250 & 4t Yams!
Location: Brussel County, England

Re: GT250A airbox, road trial pending

Post 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..
sportston
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Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: GT250A airbox, road trial pending

Post 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
dollydog
Yeah Man, the Interstate
Posts: 630
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Suzuki 2-Strokes: several gt250 ramairs

Re: GT250A airbox, road trial pending

Post 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.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: GT250A airbox, road trial pending

Post 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.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
dollydog
Yeah Man, the Interstate
Posts: 630
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Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT250A airbox, road trial pending

Post 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.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
daxman
To the on ramp
Posts: 348
Joined: Thu Nov 07, 2013 1:59 pm
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Suzuki 2-Strokes: A100 GT250 & 4t Yams!
Location: Brussel County, England

Re: GT250A airbox, road trial pending

Post 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.
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT250A airbox, road trial pending

Post 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.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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markush
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Re: GT250A airbox, road trial pending

Post by markush »

do it Yourself!
made of 0.5mm (stainless) steel sheet.
Eigenbau_Schelle.jpg
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: GT250A airbox, road trial pending

Post 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
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
sportston
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Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: GT250A airbox, road trial pending

Post 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.
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT250A airbox, road trial pending

Post 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;
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
daxman
To the on ramp
Posts: 348
Joined: Thu Nov 07, 2013 1:59 pm
Country: United Kingdom
Suzuki 2-Strokes: A100 GT250 & 4t Yams!
Location: Brussel County, England

Re: GT250A airbox, road trial pending

Post 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:
daxman
To the on ramp
Posts: 348
Joined: Thu Nov 07, 2013 1:59 pm
Country: United Kingdom
Suzuki 2-Strokes: A100 GT250 & 4t Yams!
Location: Brussel County, England

Re: GT250A airbox, road trial pending - Update

Post 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
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