Suzuki gt250 high idle

[dollydog]

250A is when they changed to the bolt on petcock. ?????????? nah, 1974/5 was when they changed to bolt on taps on the gt250 of that i'm 100% sure. when the seam on the front of the fuel tank appeared all the way round, the round fuel tap went and that seam was missing til about mid 74. have a look at a 250k tank right at the top of the tunnel you'll see what i mean but i could be wrong. unfortunatey i tend to go to sleep and wake up minus several brain cells
i've refurbed several dozen sets of gt250a/b carbs and none of them have had a vacuum take off on the carb rubber side and neither have the carb rubbers got one in. however i did find ONE 250a carb manifold with a vacuum tube built into it, but that's the only one i've ever seen. it was pretty heavily built, definitely not home made. but don't forget, i never use these carbs, so if there's a built in vacuum pipe/tube then i apologise for being a complete peasant
cheers, dd.

[karl pa]

20180826_151508 by 20180826_151438 by karl pa, on Flickr37389@N05/]karl pa[/url], on Flickr
Well I hate to make you a complete peasant My 77 GT250 has a vacuum petcock with the vacuum tube coming from the right side of the right carb.
As for the old petcock style I may be mistaken,I looked it up on alpha sports parts webite and they show the old style for k,l,m and a. Also bike bandit.
If you look at alpha sports parts, they show the A and B carbs having vacuum on right side of right carb.

[dollydog]

hi mate, ok, i'm a peasant but like i said, i don't build the later gt250's, i only build ramairs and t250's, and i only refurb 250a carbs for other people and not for me i looked on alpha sports and on the ramair carbs it's showing a booster hose for the vacuum tap, but on the 250a carb it just says hose rh, which doesn't help a lot. glad you pointed it out though because i was going to use some gt250a carbs on the gt350 project, as they are 28mm and that's got a vacuum tap on it. thanks again, i'll go and put me smock on, beany hat on and straw in my mouth before i go out for my cider
cheers, dd.

[dorT500]

............... thanks again, i'll go and put me smock on, beany hat on and straw in my mouth before i go out for my cider ..

I needed a visual on that one .......just missing the cider.

[karl pa]

Now that is a visual.

[daxman]

edit: that looks like a newer gt250 as it has rubber carburetor boots so the vacuum line may be in a different location i cant remember. it will be on the engine side of the carburetor slide.

The vacuum pipe is on the RHS carb of my 250A..

OK I'm too late now I see..

[cleaf]

carbs cleaned and bike runs much smoother now.

and to the next question. when bike is running there comes white smoke on right side exaust but not on the left side (exaust pressure is same on both)?

is oil injection working only in the right side cylider?

[dollydog]

easy peasant answer is white smoke equals oil from the gearbox being burnt. 2 stroke smoke is blue if yours is the 250a? which i think it is, the gearbox feeds the right hand crank bearing, so it sounds like the seal is leaking there and gearbox oil is getting into the crankcase and being burnt get stripping that engine down - or at least keep an eye on your gearbox oil level - if it gets too low you'll wear gears out and eventually seize the right side main bearing. hope that helps?
cheers, dd.

[karl pa]

250A is when they changed to the bolt on petcock. ?????????? nah, 1974/5 was when they changed to bolt on taps on the gt250

I must say that every search I do on 74/75 petcock keeps coming up with the old style petcock with big nut fastener, I seen lots of pictures of 74/75 GT250 bikes that have the old style petcock, all the parts books I find show the old style, so I guess we are just going to have to disagree.