Carbs

Reggie3cl said:
I have to beg to differ, took me a couple of years to fully sort my Mikuni RS 36's, I can dis assemble/re assemble/refit to the bike in the dark, blindfolded, one hand tied behind my back, and standing on one foot......
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Yeah, but didn't your carbs come off a burnt out wreck?  Not the best place to start... :D
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jeez, Reggie, what a memory....yeah, and it was probably the carbs that started the fire, I am never one to shy away from a challenge. Either that or I am really cheap :o  I did eventually get them working well, and learned a lot in the process.

Paul LeClair
 
Well .. actually, Paul, it was quite a saga, I think everyone who was reading at the time remembers it well and we're just glad it happened to somebody else. Not that anybody wishes that level of misfortune on anyone here, and you did make it quite a learning experience for a lot of us.
Bu anyway, what did you eventually discover as the problem? Mine just work. Perfectly. The only problem I had was that they fell off a few times when I first installed them, but after I made a bracket to hold them in place no problems. They stay in tune, easy starting always (hot or cold or anywhere in between), and fuel consumption 40-45% better than the Dells.

Ken
 
        Steve Wintertons land line is now connected, it's    01386833422, but be patient,

        he 'marches to the beat of his own drum.'

                    eric
 
I am a bit "between the chairs" as we say in Germany if someone can't agree to either of two point of views. I understand that Dell'Ortos were the originally installed carbs and if they are set up well and everything else is doing well with the bike, it is good to have them and they were the deal at their times. It has a reason why so many BMW of that time changed to Dell'Ortos (or does it simply mean that there were carbs that were even worse? :-[ :D just kidding...).

On the other hand, if you look for trouble free additional torque and power, better fuel consumption, improved throttle response, lighter throttle actuation, and, and, and, Mikunis are the deal, no doubt about that. They increase the fun you have with your bike by at least 50% if you like good punch from low and midrange. But they come at a price and that is not just the money they cost, it is also the fact that your bike is not original anymore as it was intended by the factory. The good news though is, that this is reversible and that with almost no afford if you keep the Dell'Ortos cleaned and dry on the shelf.

But as said: the more advanced I get in my years, the more I do care about preserving the original appearance of my bikes. Not that I would change back the SFC 1000 to red and original carbs/mufflers, but I do consider which modifications I do with keeping reversibility in mind. I started roughly 5 years ago during the project 750 SF(0) to also collect and store all necessary items I need to reverse the 1000SFC to original state within one day. Maybe that's crazy, but that's how I decided for me and my bikes. I gave up on the Jota, but if I can find a complete set of Tank, seat and side panels, I would consider buying it for the same reason. Still have the original rims and disks laying on the shelf for that very reason.

But - everyone to its own, right?
 
A big massive thankyou to Andy (Racer), had a phonecall of him mid morning today and after a breif chat had arranged to take my bike over to his this evening after work, bike now firing on all three pots, and what a beutifull sound.

What was the cause of the no firing on one pot I hear you ask, well tis a bit embarrasing i Have to say, when i got the bike the plugs were out, and it would appear that when i put the plugs in i put the wrong HT lead/cap  onto the wrong cylinder. Problem 1, the second ime pleased to say was not down to me, by pure chance Andys other half noticed that the frame holding the three coils under the tank had fractured and as a result the coils had a bad earth, a bit of checking and sorting and bike is now firing on all three cylinders.

As ive said i cant thank Andy enough, he is a true gent and very knowledgable to boot, learnt loads in the couple of hours that he worked on my bike.

So has anyone got the metal cradle which the three coils bolt onto going spare which i may purchase of them for a few beer tokens?

And finally thanks to everyone else who has offered advice over the last few days.
 
It is hard to see from the drawing on LAVERDA-Paradies site and it is a few years since I looked under the tank of a 120 but it seems to be a fairly simple plate, easy to get one made? can you show a decent pic of it?
 
Sorry to refloat such an old thread, but I'm a bit lost (yet again).

After reinstalling clean carbs, I was having some problems, as the bike would start really well, but only run with choke on. If you take the choke off, the bike will stumble and die.

I had some time today, and started investigating, and I've found some things:

1.- the far left exhaust pipe does not heat up as much as the other  It stays at around 40-45 degrees.
2.- When running, if you close the fuel taps, the bike will die, but the far left carb bowl, will not run out of fuel
3.- the smoke when running smells like fuel (a lot)
4.- there is spark in the plug. I even swapped right and left cylinder plug covers, just in case, but no change.

So... if I have fuel, I have spark and I have air, why is the cylinder not firing?

The engine is noisy and vibrates heavily, so I feel confident about the non firing cylinder diagnostic.

The bike is a standard dellorto setup and fresh fuel.

Any ideas/suggestions on where to start from?

Thank you!
 
Sounds like they need to be stripped, ultrasonic cleaned, blown out with an airline and reassembled.
 
So has your bike run at all since 2011?  You said all was OK then, so presume your carbs were working fine at that point.  If you haven't used the bike since then then the carbs could well be the problem if fuel was left in them.

If the bike has been running (which you said it was after Andy helped in 2011), why did you remove the carbs?  You say you reinstalled clean carbs...how did you clean them?  And how long ago? Are you confident you reassembled & installed correctly?
 
Hi Rob,

My bike was stopped for a long time, and re-started in 2011. After that, last year (around this time) I retook it. An ultrasonic clean was done, and Grant gave them a look-over. Everything was supposedly OK, and the bike started after so many years (you can hear it here:
)

At that time I did not check the exhaust pipe temperatures. And I don?t really remember, but I think it would run fine(ish) with no choke (in the video).

It could have happened that crap has settled down on that carb since a year ago?

(Rob, I was not helped by Andy, I just continued this thread as symptoms were quite similar after a search).

Cheers.
 
Can you pop the pilot/idle jet out on that carb to check: look through it and perhaps work some carb cleaner through the passageway whilst you're there? Shouldn't take more than 20 mins... If all seems ok then it's a carbs off and strip event...
 
That writeup is awesome.

Yes. Current plan is take off jets, follow those instructions with carb cleaner, and see how it goes.

If it doesn?t get solved, I?ll take the carbs off for another ultrasonic clean.

Thanks a lot for your help Andy & Rob!

Cheers.

 
I would look at the fuel tap filters.
Clean carbs can soon clog up again if silt/rust/crap is pulled through from the tank.
 
Tank has been cleaned and "epoxied". Taps have been cleaned as well.

I guess something survived the prior cleanup, and it needs to be done again. I?ll post back with results.

Cheers.
 
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