What have I done? Bike not starting after cleaning carbs

**vindy500** · 29th April 2009, 18:05

so my bandits having issues with bogging down at past 50% throttle so the guy at the shop told me to clean the jets with a wire from a wire brush and set the pilot screws, done. 1.5 turns out for a 1992 bandit 250 and scraped out the 2 holes in the jets in all the carbs, put it back together and it wont start, push start electric start and electric start with "start ya bastard" all not working. any ideas?

**autobatch** · 2nd May 2009, 15:50

There is a simple test to see if you have done something bad to the carb so you are not getting any fuel. Take out the plug(s) and put a tiny amount of fuel in the cylinder. Put the plug(s) back in and try to start it. If it starts and runs for a couple of seconds, you know for certain that it isn't getting any fuel. That being the case, you have done something wrong when you reassembled the carbs.

Let's assume that it does start and run for a few moments. Make sure fuel is getting into the carb. Take off the float bowl and check to see if it is full of fuel. Don't worry too much about the idle adjustment as improper setting will not prevent starting. You might have dislodged a bit of dit that has found itw way into the carb. jets. You might have to remove the carb again and blow it out with compressed air.

If the bike does not start, when you put a little fuel into the cylinder, you most likely have some kind of ignition problem. Make sure your spark plug is clean. After cleaning the plug, with the plug removed, connect the wire and hold the plug against the metal of the engine while cranking the engine over. You should see a nice fat spark in the plug.

That's a couple of things to try.
regards,
Johnny

**vindy500** · 2nd May 2009, 15:57

ive been trying to start playing with the pilot screws, (its an inline 4) and very occasionally it will start for a couple of seconds and then die again, and sometime you can hear it trying to fire and it just kinda burbles but doesnt catch. SHould i be trying

**xwhatsit** · 2nd May 2009, 16:01

Like the guy in the VT250 thread, have you set the fuel tap to `Prime' to fill the carbs first? Just leave it on prime until it starts. Vacuum fuel taps are a pain in the arse.

I got told off for scraping out jets with wire. Brass is very soft and if you scratch the inside of the jet, you're making it bigger. It might not seem like a lot but jets are very small so a gouge or scratch can make a difference.

**The Pastor** · 2nd May 2009, 17:10

yeah use carb cleaner not wire, way better idea.

i would go as far as to replace the jets now that youve stuffed em!

i find after taking the carbs off a bike, it is often hard to start them, so i just roll start it down a big hill and 9 times out of 10 it'll start up and be good.

**vindy500** · 2nd May 2009, 18:30

where would you get new jets from

**vindy500** · 13th May 2009, 17:30

took the jets into a couple of bike shops today and they both said they were fine... any other reasons a bike wouldnt start? any troubleshooting ideas i could do?

**Ragingrob** · 13th May 2009, 18:47

Spray in a load of engine start into the air box and see what happens!

**vindy500** · 13th May 2009, 19:50

tried that too :/

**cs363** · 13th May 2009, 21:14

Unfortunately this is a bit like performing surgery over the phone!

I would stop, take a deep breath and then go back and recheck everything you have touched - like are all the hoses connected to the carbs
(and correctly?) no kinked hoses, have you disconnected or knocked any wires off?
Did you do as xwhatsit suggested and prime the carbs? Is there fuel getting to the carbs? (try turning the tap to prime and undoing one of the float bowl drains, better still both of them)
Do you have spark?

One other thing - the two holes in the jets? Which jets were you cleaning - not being smart but do you know which bits are which in the carbs?

Did you have the slides out of the carbs and are they back in properly?

It really could be a lot of things, but if you are confident you've put the carbs back together exactly as they came apart without damaging anything then I would think it's probably just a hose or two somewhere on the wrong way or kinked etc.

**98tls** · 13th May 2009, 21:18

Originally Posted by cs363

Unfortunately this is a bit like performing surgery over the phone!

I would stop, take a deep breath and then go back and recheck everything you have touched - like are all the hoses connected to the carbs
(and correctly?) no kinked hoses, have you disconnected or knocked any wires off?
Did you do as xwhatsit suggested and prime the carbs? Is there fuel getting to the carbs? (try turning the tap to prime and undoing one of the float bowl drains, better still both of them)
Do you have spark?

One other thing - the two holes in the jets? Which jets were you cleaning - not being smart but do you know which bits are which in the carbs?

Did you have the slides out of the carbs and are they back in properly?

It really could be a lot of things, but if you are confident you've put the carbs back together exactly as they came apart without damaging anything then I would think it's probably just a hose or two somewhere on the wrong way or kinked etc.

Xactly what he said(good post mate) Start with making sure there getting fuel..both.

**vindy500** · 13th May 2009, 23:45

its a inline 4... but yeah. i know at least one of them is getting fuel cause i drained it, didnt check the other 3 tho... the carbs i cleaned were the pilot jet and the main jet im pretty sure, they unscrew with a normal flat head.