Jim's freebie Winter Hack, Work has commenced!

Ok. It's just u mentioned your vacuum outlets were capped on the carbs. If this is so and your petcock works on a diaphragm then it won't be allowing fuel through.

There needs to be a hose from the vacuum outlets on your carbs to the petcock.

/edit you only need one outlet / hose from one of the carbs as u likely only have one petcock.

 

Hoppie I refer you to Paul's post can you show me on the pic where the vacum pipe you're on about is? Cheers Bud.

 

Hi Jim...trawled through the internet...this is probably the best I could find...with the vacuum hose its the black one just below the number "3'' is depicted...shud go to the back of the petcock.

Item "3" is the the Fuel Outlet...

lol...this probably explains it much better than me...

http://www.bbburma.net/FuelHoseRouting.htm

 

Good diagram and reminded me that the GS has a SECOND tap where the fuel lines come out of the tank, as well as the frame mounted petrol tap.

The other thing that occurs to me is the GS500 tank is notorious for filling up with water and rusting inside out. Tiny bits of rust end up in the float so might be worth checking the drain from the float bowls just on the off-chance that your fresh tank of fuel hasn't dislodged any crap into the carbs.

 

Black plugs and dying once warm suggest over fuelling, not staving though, unless it's combustable rust

 

Doh... good point.

 

Maybe overfuelling on start up, which could be a dodgy diaphragm (hence your black plugs)
but after revving it dies ? (I'm assuming a few revvs..enough to drain what ever new fuels has trickled in...not long period of revving ?) - hence lack of fuel (engine dying) opposed to running lean since running lean requires the engine to still run (in order to change the colour of the plugs).
(This is all still guess work and assumptions )

However, without any vacuum hoses connected, the Fuel System isn't going to work properly ...and Jim has said his Vacuum outlets on the Carbs are blanked off with caps....and the fact that Jim's trying to figure out what or where this vacuum pipe is

Just trying to get the bike connected up properly first as to how it should work...

 

I am learning so much reading these posts

 

Can you come around mine and fix my bike then!
The tank has been cleaned and fresh fuel put in, (it was nice an clean already but good to start with clean slate). The diaphrams were fine, I had the carbs apart after they were cleaned to check them.
It'll run lovely on tick over for a fair few mins but the second I start to blip the throttle it starts mucking about and dying, suggest that fuel is getting into the bowl continuously otherwise I'd expect it to use the limited available fuel and cut out sooner than it does?

 

Vacuum in the tank causing fuel starvation perhaps (blocked/kinked breather).....what happens if you leave the petrol cap open?

 

Dunno will try this as well. Thanks Ducky.

 

you probably know this, but just to clarify...the diaphragm I'm talking about resides in the petcock...thats why you need the vacuum lines...from the carbs to the petcock...and the diaphragm in there can be buggered too.

 

I'm getting really worried about Hoppielimp. First we learn he's got a pet cock, now we find he has a diaphragm in his pet cock and it may be buggered!

 

OMG Read and learn..........................of my stupidity!
So I'm studying hard this week, doing a Foundation course in Fire Safety this week and at 6.30pm I think "hmm I'm gonna go and have another play with the GS......." So mug of coffee in hand a tin of cigars in my pocket Ihead out to the scene of operations! I decided to take the carbs off again and try Scortchios '7th turn of the mix screws', first of all I took the top of the carbs off to check the diaphragms are sound and the little 'O' rings in the vacum take off ports are present, they were, so next I think I'll take the carbs out again and as I disconnect the airbox I noticed the fuel feed pipe, which is hidden at the rear of the fuel tap housing, is disconnected! UH OH! I try connecting this and ...........................bugger me the f*cking things is fixed!!!! AAAAAAAAAAAAAAAARGH! Scortchios advice must have been right on the money, my previous tinkering with the mix screws DID actually fix the original problem but as I re-assembled the bike I inadvertantly knocked the fuel feed pipe off, hence the bike started ran a bit, then ran a bit rough, then cut out and wouldn't start at all. It was something very simple in the end, mainly me!
Thanks everyone for your help, especially Dave and Paul (whose link proved very useful).

 

Right so the project continues with more pics but first photographic eveidence of the engine running sweet as a nut! You'll have to take my word for it but you can see the rev counter on 1200 rpm and the neutral light!


A slightly buggered Diaphragm, this one was found to be kinked over on dismantling so I replaced it with one form the spare set.


And a busted Vacum take off tube so Irobbed a top from the spare set again.


Carbs back on and ready for the air box,


a tip here, when fitting the air box remove the filter, stick your hand inside and feed the rubber boots onto the air intake of the carbs with your fingers rather than just peushing the air box onto them. When I took the box off Inoticed that the lip of one of the boots had got twisted over and so wasn't getting a seal against the carb air intake! Does that make sense?



Whilst all this was going on I was also starting on the ebay acquired luggage rack

 

You

Prat!

Glad it's working though

 

Nice one Jim and Dave!!!

 

Glad your back on track (now theres a thought, sat 17th???perhaps)

 

It was only fuel starvation because he introduced a new variable and didn't tell anyone!

Should have guessed by his sig really