If anyone fancies earning a few extra quid balancing my daytona 600…
I’ve had enough of staring at the carbtune attempting to improve matters, while gradually making the situation worse. Triumph can’t fit it in until next week.
Have you got a manual for the bike? On my Honda carbs #3 and #4 are linked, and #2 isn’t adjustable. You have to adjust #4 to #3, then #3 to #2, which brings #4 with it. If you don’t do that then you end up chasing your tail until you throw the Carbtune down the road and under a bus…
The manual threatens death to anyone touching the ‘forbidden’ screws. On the Daytona the adjustment is one screw between 2 and 3.
1 and 2, 3 and 4 are linked. You would think that should make life easy… I’m not 100% sure the stepper is adjusted correctly, and after my fumblings I’m certain that the ‘forbidden’ air idle screws are well off. Problem is, there isn’t sufficient vacuum to hoist the sliders on the gauge, so balancing left 2 with right 2 is difficult to say the least. It currently ticks over, but bogs down the minute I open the throttle.
Hmmm… in that case I have no idea :blink: hopefully Rob will be along in a minute 
He’s not a fan of fancy new electrickery though…
There is waaaay to many things on that trumpet .I am still of the feeling that stepper motor nonsense is getting a spooky reading… something is fukin it up . I say remove the whole ferking lot and bolt on a set of ZZR 600 carbs 
I’ve got a spare set of CB carbs in the loft somewhere…
I would love to bolt carbs on. Not sure how we would run distributor though 
I guess I’ll have another go today :crazy:
Spotted a misaligned air intake, but it’s before the airfilter, so can’t see that being the problem. I have a k and n filter in there which I have never oiled, so today I’ll get some filter oil and see if that helps. Perhaps the root of my problems is too much air. If the manifold pressure sensor never sees a decent vacuum, then maybe this puts everything else out. If it does create more vacuum, then I might be able to get a reliable reading on the carbtune at 5000rpm and get them balanced.
When I first carb balanced my GPz I discovered where the Carbtune was made a difference, so now I move it about until the bars can be seen to clearly move (rather than twitch a little) and so be adjusted.
Also those adjustment screws can be very sensitive. I tend to have the engine run a good 5 minutes to get warm and allow heat expansion to occur on the carb screws and then with a very light touch turn them. Then flip the throttle and see if I got a real balance or a false one.
Have you got the little plastic restricting tubes inline between the Carbtune and the engine? If so you might try removing them as they’re supposed to dampen the effect on the rods.
The length of tubing can affect the Carbtune too, maybe try having a shorter length between it and the engine.
I’ll give that a shot. It ticks over nicely, but the minute I crank the throttle it dies. I’m thinking that HAS to be badly synched throttle plates.
Could be lack of air too. It is fouling the plugs?
Whenever you can rule out electrics being the problem then it never hurts to look at the spark plugs to see what colour they are and hint to what the fuel mix is like.
Oh, and pre filter/ air box holes will unbalance the air/fuel mix on post 1990 bikes because of EC noise regulations made manufactures readjust pre filter air intakes and jet sizes accordingly.
To give an example the pre 90’s GPz had 2 open to air holes in the air box prior to the air filter, and post 90’s only one hole + extra foam filter over this hole was added. Main jets went down from 132.5 to 100 in size. So as you can see in this case example Kawasaki limits the air into the carbs and to keep the fuel mix near optimal reduce themain jet by 32.5.
QED allow more air into the box you have to increase main jet sizes to allow more fuel to mix into the increased air volume.
Well I left the ignition on while I was working so battery is currently charging…
I have taken off the throttle bodies and taken the jets out. They look a bit scummy, but I guess the important bit is the needle valve itself, which looks ok. I have a spare fuel rail here, so I’ll swap them over. Petrol pooling in the throttle body rubbers, normal?
Last time I took off the rubbers I sealed them back to the block with some gasket sealer. I don’t know if it helped or not, so this time I sanded back the mounting plates, so that when I put the o ring back in it stood a bit proud. Last week I wrapped the old rubbers in silicone tape, which seems to have held up well. I can’t for the life of me see how air could be sneaking in there. I have cleaned and oiled the k and n filter. As far as I can estimate, the throttle plates are synched. With the air idle bypass screws shut, the carbtune shows them as equal at idle. Not enough vacuum in the bodies to excite the carbtune at anything over idle, but I’ve mucked around with identical allen keys etc to try an ensure the gap is as close as possible at greater throttle openings.
Ive taken the plugs out, they look ok, a bit on the white side but nothing spectacular. With the throttle plates fully shut, the stepper motor gap is 0.5mm, as spec.
Position sensor is working fine, as checked through Tuneecu.
Not sure what else to do now, so I’ll go back out and stare at it for a bit longer, and begin to reassemble it I spose. :crazy::crazy:
They look a bit scummy, but I guess the important bit isthe needle valve itself
Petrol scum gets everywhere I’m afraid, but a bit of acetone (nail varnish remover) from the chemist will dissolve that.
Petrol pooling in the throttle body rubbers, normal?
Not sure what you mean, but probably not. If the jets are coated then perhaps the float valve is too and what you see is a bit of overflow? Again with the acetone and brush.
Ive taken the plugs out, they look ok, a bit on the white side
I’d expect a lighter shade of tan with K&Ns because that is what K&N’s do, allow a bit more air through.
Not sure what else to do now
Nor me not owning or having worked on that bike to learnby experience. But I think I’d be inclined to look at components involved in fuel delivery, as it seems by the overall problem is air getting in is ok at idle and therefore probably ok at throttle too as too much air is getting into the mix causing the engine to stall.
So my thinking goes, wheres the fuel gone?
You may have already tried this, but, worth a shot - from what I’ve read part of the issue is that you’re not getting enough vacuum to be able to read the Carb Tune properly and therefore balance the carbs. Have you tried the carb tune upside down? Here’s an excerpt from the manual:
"The manometer must be used vertically for a scale starting at 8cmHg (centimetres of mercury. 1 inch=2.5cm 1cm=0.4inches) and going to 42cmHg. Most bikes have readings higher than 8cmHg, but some bikes such as R-series BMWs and two strokes can have readings lower than this.
To get a reading below 8cmHg remove the plastic cable clip from the slot at top of gauge and insert it into the slot at the bottom. Push cable clip into slot from front of gauge. Hang the Carbtune Pro upside-down.
Ignore the scale figures. Zero will now be around 16cmHg on the scale but the full width scale graduations will still be 2cmHg. Absolute values are not important. Comparisons are important."
I think I have sorted at least one of the problems…One of the jubilee clips that hold on the throttle bodies was fouling the return of the two right hand plates. Bloody stupid design…
Took it down the road and ran out of fuel before I got 100 metres. I’ll nip and get some petrol when the shopping trolley gets home, fingers crossed.
Stretch, I didn’t know that! I should probably have spent more time reading the manual…:Whistling:
Problem solved!!!
I traced the problem back to the brand-bloody-new fuel connector. Sexy stainless steel etc, but was letting virtually no fuel through. I bought 2, so I bunged the other on and its running like a champ.
Thanks to everyone for suggestions and advice