Hiya, fitted a set of cbr600 carbs to my gt engine and its always running rich, I'm running a facet fuel pump that runs at 3psi and have fitted a fuel king fuel pressure regulator to drop it back down to 1.5psi.

Even having fuel king fuel pressure regulator it still runs rich, I've adjusted the fuel pressure regulator so its wound right off, so it drops to 1.5psi is that right???

The carbs have been refurb'd and jetted by bogg brothers.

How do you know its running rich?

You say bog bro's have done the jetting. Did you tell them its for your engine?

What's are the jets its using?

Generally more information needed.

Max

The exhaust stinks of petrol and its doing shit mpg.

Yes told them the exact spec of my engine.

I dont have clue.

Strange,

I wouldn't have thought BB's would have incorrectly jetted them.

You need to find out what the jets are throughout the carb's.

Take the bottom's of the carb's off and you will find the jets, they are brass. They should have a flat head screw drive on the top of them. The small one is your idle jet, The larger one contains your air corrector jet, emulsion tube (which is the long piece in the middle, Marked f30 probably) and your main jet which is at the bottom.

The numbers will either be embossed on the sides, or the top.

Just check one outer carb and one inner carb.

or you could just ring them up and explain your problem.

Neither would I.

Could it be the fuel pressure regulator? I've wound it right off so the brass adjuster is finger tight and locked it in place.

Edited 10 November, 201015 yr by Coldforged

Only if it was way too high, I would expect you to have fuel leaks as well as this symptom though.

Check the jets, Or find out what they have put in.

As well as checking what other people have used in the FAQ section, Here:

http://www.clubpolo.co.uk/forum/index.php?showtopic=205846

sure there's a GT in there.

if you just sent the carbs to bogg bro's for setting up then it does say on the website that they are only roughly setup as every car is different so they will only work well enough so you can get it too them for the fine tuning, i have used bogg bro's a couple of times and the old chap there really is s**t hot, he had my carbs setup so well that going on the emmision's readings on his machine they were good enough to even pass a standard car with a CAT!

btw, i wouldnt start messing with your carbs unless you have all the correct setup equipment as they are very temperamental...

but tbh my car still smells very rich but mpg is ok considering my setup (about 245miles to a tank) and it passed the mot fine this way

craig

I know i should have the car RR and setup properly but i cant afford it at the moment.

First thing I did was check for fuel leaks and there isnt any.

I'll ring them tomoz

Edited 10 November, 201015 yr by Coldforged

well until its properly setup i would take it easy as if its running rich or lean you can cause damage to the pistons etc bla bla, plus its only £80 for the rr and tune up so dig deep and get it done, its definitely worth it! :)

if you just sent the carbs to bogg bro's for setting up then it does say on the website that they are only roughly setup as every car is different so they will only work well enough so you can get it too them for the fine tuning, i have used bogg bro's a couple of times and the old chap there really is s**t hot, he had my carbs setup so well that going on the emmision's readings on his machine they were good enough to even pass a standard car with a CAT!

btw, i wouldnt start messing with your carbs unless you have all the correct setup equipment as they are very temperamental...

but tbh my car still smells very rich but mpg is ok considering my setup (about 245miles to a tank) and it passed the mot fine this way

craig

Checking what jet sizes he has isn't messing about with them.

Your choices are ring them up and see what they say, Or cross reference your jet sizes with the ones in the link i sent you and see if they are way off.

Max

well everytime the chap at bb took the carbs off to fiddle with them he had to arse about for a while re-balancing them again because unless they go back in exactly the same position the air volume inside the inlets would be ever so slightly different causing a rich or lean mixture in every piston chamber

plus hes just going to say that he needs to bring the car in to be properly setup

Edited 10 November, 201015 yr by dubownerbilco

I am doing trust me, I'm driving like a granny just incase!

I'll ring them up tomoz see what they recommend for jets and then strip my carbs down this weekend and check.

Right gone to start the car up this morning to go to work and its not started. When it did eventually start if i even just thought about using the throttle it would cut-out or just stall.

I'm sick and tired of it now, my car has made me late that many times that I've lost my job now!

Right just got off the phone to bogg bro's they said that theyve def not fitted the wrong jets and i believe the old fella. He says its down to my fuel pressure regulator, he asked what pressure I'm running and i said i was told by you to run 1.5psi, he said that they should run at 2.5 to 3psi thats whats my problem.

So I'm gonna give that a try and see if it starts.

Edited 11 November, 201015 yr by Coldforged

Adjusting the fuel pressure won't affect how ruch it runs, it'll just cause the carbs to overflow. Bogg Bros will have drilled the jets to the correct size, but as Bilco said you need everything set up at the same time for it to run right. The good thing at least is that there is enough fuel being sent through, but ignition timing, needles, balancing all need setting up in order at the same time Which is what they do very well at Bogg Bros!

Had it done there myself and it was more than worth it

I know i need to take it to bogg bro's so its set up properly. But first i need to get it so its running and driveable!!!!!!

Edited 11 November, 201015 yr by Coldforged

Could it be something else causing the poor running? If its stinking of fuel it could just be that it's not igniting it. Could try new plugs/leads/dizzy cap/rotor and see if it helps. And take it to someone that has a timing light and set that up.

Sorry to hear about the job I know how it is having to rely on a car that you can't rely on.

Adjusted the regulator like bogg bro's said and it seemed to want to turn over a lot better now. I've noticed though that one of the carb rubbers has split aswell now though! So tryin to find a replacement.

Its deffently not the rotor or dizzy cap as there new and so are the plugs. Will price up some leads tomoz.

Cheers mate

Edited 11 November, 201015 yr by Coldforged