View Full Version : Gsf250 carb issue after cleaning
2000 gsf 250 vz-v
25th February 2019, 19:27
Hey there i have a 2000 suzuki gsf bandit 250 vz-v i have had it for over a year and really enjoy the performance from the little 250. My problem is i cleaned the carbs on w.e and tried to replace the main jet with a larger jet as i have an aftermarket air filter and exhaust but when i put it back together the bike does not want to start and crash starting it will run really rough sounds to me like its running rich but not 100% if i keep revs up highish it will stay alive but sounds terrible but if i let off it dies straight away even with the old jets in i have the same problem i cleaned everything fairly thoroughly i did not reset float heights as bike was running really well before this cleaning attempt i used compressed air and tiny wire also. Im really not sure whats going on any help would be greatly appreciated as i dont want to take it to shop but will do if its beyond my ability any questions i am happy to answer about it cheers!
OddDuck
25th February 2019, 21:07
Well, welcome to a bottomless pit of trouble.
Right:
1: what do the spark plugs look like?
2: Inlet manifold vacuum still good?
3: check your fuel tap, is it actually flowing fuel when switched on and the engine is cranked over?
4: were there any old rubber seals (O-rings etc) that had gone a bit flat but were re-used?
5: what's the state of charge of the battery?
6: how old is the petrol?
7: what's your setup like, working space, tools, time, cash, access to people with experience?
FJRider
26th February 2019, 07:51
Try putting the original jet in it and see if it runs (better .. ??). Just changing the air filter wont make a huge difference.
And how much bigger was the jet you put in it ... ???
sidecar bob
26th February 2019, 08:18
It will take a lot more than a bigger main jet to compensate for a free flowing air filter with CV carbs.
Go back to standard jets & filter & start again.
Unless you spend a fair chunk of time with considerable knowledge on the topic, invariably fitting free flow air filters to cv carbs makes the bike less powerful & harder to ride.
Not to say there isint something else wrong that's causing this issue.
2000 gsf 250 vz-v
26th February 2019, 09:29
Thanks for answering the battery is fine was running well even with new filter before i pulled carbs. Spark plugs are fine, even when i put old jets back same issue but worse. Im not sure how to test vacuum? I tightened everything up fairly tight as tight as the wearing screws would go. Unfortunately do not know anyone who has motorcycles as quite new to Wellington. I have most tools to work on bike and garage space. I will try check the fueling but was all running well before hand so unsure there. Thanks for your answers
2000 gsf 250 vz-v
26th February 2019, 09:31
It must be getting fuel as the float chambers are always full when i take them off, i only noticed rubber seal o rings where the inlet for the synchronous device to go no other seals came out
sidecar bob
26th February 2019, 10:08
Is drew about ?
husaberg
26th February 2019, 10:29
Is drew about ?
341037
Hey there i have a 2000 suzuki gsf bandit 250 vz-v i have had it for over a year and really enjoy the performance from the little 250. My problem is i cleaned the carbs on w.e and tried to replace the main jet with a larger jet as i have an aftermarket air filter and exhaust but when i put it back together the bike does not want to start and crash starting it will run really rough sounds to me like its running rich but not 100% if i keep revs up highish it will stay alive but sounds terrible but if i let off it dies straight away even with the old jets in i have the same problem i cleaned everything fairly thoroughly i did not reset float heights as bike was running really well before this cleaning attempt i used compressed air and tiny wire also. Im really not sure whats going on any help would be greatly appreciated as i dont want to take it to shop but will do if its beyond my ability any questions i am happy to answer about it cheers!
OP i wouldnt faf -arround with a mini fours carburetion. Unless i had very good reason too,put it back to stock, or look up a website specific to the the mini bandit.
HAve a look there may be alternative jetting kits on the net similar to dynojet.
https://www.ebay.com/itm/Suzuki-GSF250-GSF-250-Bandit-6-Sigma-Custom-Carburetor-Carb-Stage-1-3-Jet-Kit-/331934692235
Failing that look for ripped diaphragms and airleaks.
Not sure from your post if its still running the original airbox.
If its not you will likely never get it right.
2000 gsf 250 vz-v
26th February 2019, 10:44
The thing is it runs the same with original set up and new jets i changed main jet from 97.5 to 107.5 neither run correctly now it doesnt want to start only crash start sounds boggy as while running and cuts out if i dont give it gas
husaberg
26th February 2019, 11:15
The thing is it runs the same with original set up and new jets i changed main jet from 97.5 to 107.5 neither run correctly now it doesnt want to start only crash start sounds boggy as while running and cuts out if i dont give it gas
So it was runing fine with the airfilter and can before you took it appart?
Now it back together its running crap?
Ginge09
26th February 2019, 11:41
Main jet won’t affect starting. Idle circuit will. Stop playing with the main jet.
Is the diaphragm seating properly? Does it have a pin prick hole in it?
2000 gsf 250 vz-v
26th February 2019, 12:27
Yes was running fine with exhaust and filter, im starting to think vacuum leaks maybe it actually runs better with the larger jets now than smaller ones have swapped them out multiple times now testing, the slide diaphram if thats what your talking about that suctions is working fine i took time to check it sealed properly cheers
2000 gsf 250 vz-v
26th February 2019, 13:14
Its still running original airbox but with gs500 filter that fits nicely im not sure if maybe it needs new hose clamps for the intake to engine and airbox to carbs as i do struggle a little to get them more than nipped up as screws are wearing out but i go as far as i can till the ends are touching
nzspokes
26th February 2019, 13:55
Get it running and spray a little water over the carbs and see if it coughs or revs. If it does you have an air leak.
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2000 gsf 250 vz-v
26th February 2019, 17:48
Got home from work today and tried to get going still rough at first sprayed brake cleaner over while idling high as and would straight away kill it so took everything off again and had a real good go at tightening tubes up did it as best i could withought stripping the screws and fired it up and went for a little ride actually wanted to move at low throttle now still not running great but definitely better than yesterday so i think i found the issue and im hopeful i can fix it with some new hose clamps👍 Cheers guys will let you know how it turns out on the weekend
husaberg
26th February 2019, 18:25
Got home from work today and tried to get going still rough at first sprayed brake cleaner over while idling high as and would straight away kill it so took everything off again and had a real good go at tightening tubes up did it as best i could withought stripping the screws and fired it up and went for a little ride actually wanted to move at low throttle now still not running great but definitely better than yesterday so i think i found the issue and im hopeful i can fix it with some new hose clamps👍 Cheers guys will let you know how it turns out on the weekend
Get some rubber grease and check the inlets and rubbers for cracks, when you have them off i see no reason for new clamps?
You can temp repair clacked inlets with Silicon but it will not last
2000 gsf 250 vz-v
27th February 2019, 06:00
I didnt see any cracks but will check again👍
speedpro
24th June 2019, 15:04
Just saw this. That is a huge jump in jet size. How has it all ended up?
FYI - tipping in more fuel will not make more power, unless it is actually running lean before. Even then you need to achieve the correct fuel ratio to make power. Carbs on those 4 cylinder bikes cause motorcycle mechanics to have nightmares which is why they sometimes won't touch them. A newer bike shouldn't be a problem.
The isse sounded like not enough fuel, or lean due to a leak. Stock is best I would suggest. It's a long slippery slope if you start playing with things.
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