Rusty I had mine running yesterday on carbs but fuel was leaking and think I need another regulator . I was gunna ask what does yours Rev like on wot ? My Rev needle for the counter was going back to the stop near enough and engine was sill reviving . Red line starts just before 6000 rpm and finishes at 7 . Car sounded nuts and revved up lovely excited now 

2 hours ago, Turbobandit said:

Rusty I had mine running yesterday on carbs but fuel was leaking and think I need another regulator . I was gunna ask what does yours Rev like on wot ? My Rev needle for the counter was going back to the stop near enough and engine was sill reviving . Red line starts just before 6000 rpm and finishes at 7 . Car sounded nuts and revved up lovely excited now 

What fuel pump are you running and where's the fuel leaking from? 

Revs ok now, it would die when i tried to rev the engine before i cleaned my pilot jets. Need more info! What exactly do you mean by how does mine rev? Bar the leaks hows your's running?

Original pump with fuel

pressure regulator . It’s leaking fuel out of back of carbs by how does yours revs I seemed to have no limiter anymore and engine rpm will go off the clock . Mine was running fine ticked over right away and revved up good just on tick over would leak fuel out of the back of carb 

1 minute ago, Turbobandit said:

Original pump with fuel

pressure regulator . It’s leaking fuel out of back of carbs by how does yours revs I seemed to have no limiter anymore and engine rpm will go off the clock . Mine was running fine ticked over right away and revved up good just on tick over would leak fuel out of the back of carb 

If you’ve got a cheap regulator it might not be working well enough, the high pressure in an injection system can overwhelm them when you’re trying to bring it down to ~3psi I think. That or your float valves aren’t sealing properly. Try turning your regulator down further?

 

Rev limiter thing is odd; never revved mine high enough to know if it’s got one but I’d assume so. The 1.4 8v drops off a lot in torque after about 4500 anyway so no need for me. With the carbs on my engine does seem to Rev higher a lot more freely (still power over 4500) , don’t know about the 1.6 but maybe it’s just revving freer and you’re not used to it.

 

Many limiters work by shutting down the injectors which obviously won’t work with them removed. It’s not revving itself is it? I’d probably just go easier on the throttle in this situation haha

On 27/11/2020 at 22:15, dvderlm said:

Sorry, should have noticed the ping post.

 

Ignition too far advanced will pink/det and be low on power.

Not enough advance will have poor vacuum and feel unresponsive. Will be high HC with 4gas emissions tester.

 

I found map sensor for Dignition was way still way off with the twin carbs as much lower vac. That might not be the case with motorbike slide carbs,

 

Hi again, got another (probably daft question) 

Drove a few miles to pick up the replacement ht lead.

Seems to be driving very well but there’s a high pitched noise at full throttle that I only notice with the windows down.

It’s troubling me a bit as I can’t tell whether it’s pinging or just induction noise. How obvious does pinging actually sound?

It’s definitely not like the pinging I heard before blanking air jets, which was loud enough to be heard over the exhaust, induction and tires/wind with the windows open.

Don't see why not. IR means you don't burn yourself.

 

Just picturing Italian supercars being tuned by cooking pizza dough balls on the exhaust manifold.

"The Lamborghini Aventador v12 layout can make enough pizza bases for a family of six in one lap of Imola."

Pinking knock sounds like little man with a pneumatic hammer and ringing anvil under the bonnet.

http://www.dwjenkins.plus.com/knock.wav

 

Whistling sounds like much higher note, maybe a small hole at the carbs, but you've sealed air correctors?

 

1 hour ago, dvderlm said:

Pinking knock sounds like little man with a pneumatic hammer and ringing anvil under the bonnet.

http://www.dwjenkins.plus.com/knock.wav

 

Whistling sounds like much higher note, maybe a small hole at the carbs, but you've sealed air correctors?

 

Thanks for the audio sample it’s so hard to find examples online!
Its not even whistling per se, I think it might just be my ever noisy tappets mixed with unfiltered induction roar coming straight at the bulkhead.

hope so anyway!

Back again. Made the journey alright though not without slipping half my throttle cable which slowed me right down haha. 
On the richened up pilot screws the plug that I could get to now looks pretty sooty, but white ish on the positive electrode, but this cylinder was also reading much colder than the others on my thermometer.

Ive adjusted all the screws to bring the temps much closer together (about 280C at idle) and my carbalancer now gives a much more consistent reading. 
Thing is, this has made the idle note seem a lot less stable, you can hear it almost stumbling at the exhaust.

Im wondering if the noise I’ve been hearing at wot is actually pinging as I can see no indication it’s been running particularly lean, with the sooty plugs + exhaust very sooty + pretty rubbish fuel economy. I’ve just received some 145 main jets that I might try but I’m worried this will just make my fuel economy worse haha.

Anyone got any ideas? 
cheers and happy xmas 🍻

Thought your noise was a whistle not anvil clatter. You'll get pinging under moderately heavy engine load, such as climbing a hill one gear too high.

 

Idle stability can be improved with vacuum controlled extra advance.

With closed throttles at idle there's poor cylinder filling.

1 hour ago, dvderlm said:

Thought your noise was a whistle not anvil clatter. You'll get pinging under moderately heavy engine load, such as climbing a hill one gear too high.

 

Idle stability can be improved with vacuum controlled extra advance.

With closed throttles at idle there's poor cylinder filling.

I’m less sure now I’ve improved my throttle linkage. It’ll pull well Basically but when I get to the powerband I can make the ping/whistle/bla bla bla appear or reappear by backing off the throttle slightly for a second while climbing through the Rev range. There’s a very noticeable point of throttle where the noise appears/reappears. It seems to flatten out and stop pulling as hard when this happens 

What sort of RPM? I'd expect max centrifugal advance by 3500 to 4000.

 

It might just be leanness. Closing throttle plates usually enrichens slightly and pressing pedalcan squirt fuel from an accelerator jet.

Can you pull the choke on at this point? If that richness improves things, you need more fuel.

 

If you can't tell then you'll have to invest in a wideband lambda or a rolling road session.

 

 

Are there different needle profiles for your carbs?

Sorry I'm more of Weber, Pierburg, Dellorto fixed choke enthusiast than bike carbs guru, where I'd be trying different emulsion tubes or resort to blocking holes from Vizard's advice.