Too rich-where to start?

There should be no need to run on B7ES plugs, too hot, may give problems down the line.
 
Chuck3CL said:
Big improvement now. I did a number of things at once so I can't be sure which was the most significant, but I'd say the replacement float valve and choke slider assemblies were the most effective.

1) New float valve assembly, needle valve, fibre washer and brass seat. See attached photo comparing old and new float needle. Also the new seat has 4 fuel side entry holes instead of 2. The needle is bigger and a different seal material.
2) New Choke Slide assemblies including all mounting parts. See attached photo. The seal seat is flat on the new, distorted on the old. Could have been leaking.
3) switched from BP8ES to hotter BP7ES plugs.
4) after installing new parts I re-set the float levels to 18mm and balanced the carbs using my Carbtune.
5) Had reduced the accelerator pump volume, but I think I will now return this to previous setting - probably not the problem.

Now, starts instantly, choke off right away, solid fixed idle, smooth running through transition and into WOT. Purrs.

Thanks for the help.
Click to expand...

Great feedback, thanks for that. It is for a reason that people like Piet etc. recommend a FULL rebuild when carbs need reconditioning. Yes, it is expensive to replace all needles, jets, sliders, valves etc. along with the gaskets and washers etc. etc., but if you want to have the bike running like it was new, the carbs need a really full service with all exchangable parts beeing exchanged.

And then it needs a proper base setting of ALL components, starting with the float hight, the choke sliders, the sliders, the idle mixture screw, the needle hights etc. etc. etc. If that is all done properly, there is barely a chance the carbs are the issue afterwards.

I once was invited to a community members home, who presented me his freshly restored Jota that would not want to idle properly. In fact, it shot itself off after maybe 10 - 15 Secs of running. I asked what he had done to the carbs. "Full service, everything set to factory specs!". Long story short, the choke sliders weren't adjusted, the idle screws all on different settings to compensate for that. After setting all idle screws to 1,5 turns and the choke sliders to completely close and run equally up when opening, the bike started instantly and kept running...
 
An important addition to "Start with the basics" would be to check for proper valve clearance. I know Laverdas aren't that sensitive but if they are too tight sealing is affected when the engine is hot.
Also keep in mind the old adage," Most carb problems are electrical". Many electronic ignition systems misbehave if the voltage to the system is below 10 volts. If you are running the original charging system with lights on, low voltage is in the realm of possibility. 
 
Not in this case. I'm running Ignitech with Hall-effect pickups, Nology coils w/ new h.t. leads, new alternator, new rec/reg, and new battery. Valves were re-shimmed.
Carbs were the only culprits left standing.

 
1) New float valve assembly, needle valve, fibre washer and brass seat. See attached photo comparing old and new float needle. Also the new seat has 4 fuel side entry holes instead of 2. The needle is bigger and a different seal material.

I guess my earlier response about putting your old needle/seats back in didn't make sense, for some reason I thought, that you had just rebuilt the carbs and had replaced things like the needle/seat, re-reading I have no idea how I thought that, old fartism (Ronism?) I guess :D

Stu

 
Not out of the woods yet-- unfortunately.
The upgrades to the carbs did improve the performance but after a 100km ride all 3 plugs are once again coated in dry carbon and cause misfire. Still too rich (Lav, not me, Dman). Runs well if the plugs are cleaned.
What next? Any experience or advice on moving the main K1 needle one (leaner) ring position from middle?
Or another main jet size?
Advance map is one of the basic redax shapes. Not sure changing the advance would help?
Has anyone tried 91 octane?
 
All unleaded fuel leaves black soot on the plugs these days.
I have never had to move to B7ES or move the needle height on a triple.
Have you discussed the problem with Red?
 
Chuck3CL said:
Not out of the woods yet-- unfortunately.
The upgrades to the carbs did improve the performance but after a 100km ride all 3 plugs are once again coated in dry carbon and cause misfire. Still too rich (Lav, not me, Dman). Runs well if the plugs are cleaned.
What next? Any experience or advice on moving the main K1 needle one (leaner) ring position from middle?
Or another main jet size?
Advance map is one of the basic redax shapes. Not sure changing the advance would help?
Has anyone tried 91 octane?
Click to expand...

91 wont help, stick with 98 or run a drum of av gas through it  :D
Have you tried leaning off the mixture screws a whisker ?
 
As mentioned earlier in the thread, have you checked your air filter? 
Is it clean, what type is it?   
If it's a Unifilter, and it is over-oiled, then that may contribute to the richness. 
I use aircon filter material, which works well.     
 
Laverdalothar said:
I'll ask again: you are sure it is not oil?
Click to expand...
The oil level on the dip stick hasn't budged and all three plugs look identical in black soot. I would thing burning oil would show up as a loss on the dipstick and would expect cylinders to look different. Oil usually has a wet look, not dry soot. If you know of a better test for oil let me know.
 
tom3c75 said:
As mentioned earlier in the thread, have you checked your air filter? 
Is it clean, what type is it?   
If it's a Unifilter, and it is over-oiled, then that may contribute to the richness. 
I use aircon filter material, which works well.   
Click to expand...
Air filter is a clean piece of aircon material only in the OEM black filter box.
 
In 1995 when I bought my first Moto Guzzi Sport 1100, I changed exhaust and got rid of the airbox (youthful indiscretion). After fiddle-farting around with the jetting for several weeks and trying lots of list-serv advice without being able to get it right, I did take one piece that changed my fueling life: Go to a dyno, me son. Stop guessing. Correct fueling is simple science. Well, a few dynopulls with a sniffer confirmed the settings were way off. Since then, I never tune any fuel delivery system without a dyno and air-fuel ratios telling me I'm on the right track.

Every time I buy a MC with Dell'Ortos, they come off to be placed in a nice box and are replaced with Mikunis. Much better at holding a tune over the long-term, easier to jet correctly, they make more power and are more efficient. Last year is was the PHM40s that came off my second Moto Guzzi Sport 1100, replaced with Mikuni HSR42s; and when I bought my RGS two months ago, Redax was my first point of contact for a rack of Miks. You won't regret it, even if it seems like a bit of an expenditure, plus, it's a fully reversible mod.

Kristian
 
It's not rocket science how to make a standard Laverda run as it should.
Been done thousands of times in the past (and present).
The ignition upgrade should only help it run better.
Rather than go to non-recommended plug grades and non-standard carb settings, maybe get an expert to look at it?
 
Solved! Discovered the problem and it certainly wasn't what I thought. Spoke to Maurice, explained the problem and sent him a pic of the carboned plugs. With his considerable experience and intuition he figured it wasn't the carbs but something else. So I changed my test procedure and, instead of cleaning the plugs and going out only to find it ran well again for 20km then sputtered, I let it cool and went out without cleaning the plugs. Same behaviour, ran well then sputtered. Heat! Also noticed when it missed the electronic tacho needle driven from the Ignitech blipped. Therefore the clue, not missing because of fouled plugs, missing back at the timing pickups.
Discussed with Maurice again. We both came immediately to the likely cause--magnets at the Hall-effect sensor marginally aligned and being affected by heat. Yep. The magnet collar assembly, although aligned at TDC, was off by a few mm longitudinally so they worked for the past two years but became marginal recently. I re-aligned the collar to make sure the magnets were spot-on aligned to the Hall effect sensors and problem solved.

(As an aside, I also disabled the accelerator pump, took out the slider arms and wish I would have done this a long time ago. Still have smooth throttle roll-on/off and easy throttle on the wrist now.)

Big thanks to Maurice---again!

 
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