I've only really had to mess about with Weber's for cars in the past and I think that the 2 stroke bike carbs are much simpler/agricultural so less to go wrong. Is the fuel flow metered solely by the slide position or is there also a vacuum metering? I'm probably not being too helpful here
No thanks Harry, you are being helpful as all the members are, yes me thinks the vacuum diaphragm could well be metering the fuel supply, which with the dummy supply it's not getting at the moment.
I would investigate all that is rubber from the diaphrams to the fuel pipes themselves for air leaks and low flow. Age and standing may well have cracked more than is visible.
Stick a plug tester in line .. that way you’ll see straightaway if it’s sparking when it stops running I’m leaning to fuel as some others above - flooding due to floats - but only because that’s what I found recently on a 2 stroke I got running after about 30 years standing .. How long is it running before stopping ?
New set of correct heat range plugs is worth getting, to help initial startup and running even consider a slightly softer/hotter running set but don't even think of riding it with softer plugs or you'll be holing pistons. Check both plugs are sparking and that static timing is correct then si long as you have fuel you should be good to go. Very simple technology compared to modern machines but still need to be accurately set up.
Have you given the carbs a good clean If your not using a vacuum tap you need to block off the connection from tap to carb it's usually just one carb that operates the vacume tap Could be crank seals
Hi Matt, It runs for just a few seconds now or it did until i found the oil feed union had snapped at the pump feeding the left hand pot, a mate in the village had a spare one which i have fitted now the fun begins trying bleed the lines...oh hang on i need the engine running to do that. Just come in and had tea it can wait till tomorrow now i will do a pre mix of fuel in case i am lucky.
I bought it a couple weeks ago as a non runner, i have never been into 2 smokes but 50% of my fleet are now strokers. No history other than its quite a rare model being a 1970 Suzuki GT250 they never appeared in the UK until 1973.
Yes did all that , and removed carbs again today and checked all the jets, i have reversed the floats brass plates that shut off the float needle jet by that i have lowered the float height rather bending the tangs. Yet to be tested.
I would strip the carbs again and ultrasonic cleaned when I was rebuilding my T350 had to do it 3 times and replace the jets Not sure if the GT 250 carbs are the same as T350 but there's a jet in the float bowl that isn't shown in the parts books
Is it the one with low pipes (Hustler) or the other variant which has a higher exhaust like a scrambler? The Hustlers are quite quick for their size & age. Rode one several times back in the day.
Yes Jez it has low pipes, drum brakes all round, and an usual shaped remote headlamp, and no indicators. very similar to this minus indicators .... same colour
After several times removing the carbs and cleaning, points re- gapped and engine re-timed the same symptom kept occurring, after a couple of mins going down on the left hand side pot. Just fitted a pair of new coils this weekend but daren't try to kickstart it, i foolishly strained myself carry a lot of furniture last week creating a massive external pile (nice). I have just got to be patient and hope the problem gets better soon. Thanks for the interest mate, i bloody hate being immobile don't get old .
