Middle pot misfire

Vince said:
This has helps on my Pantah,Dels also and a few Laverdas.One of the locals uses tiny number drills in a hand turned chuck to clear hard deposits in the idle passages.Even after Ultrasoniced they sometimes don't move.Take care not to snap them, or remove metal if you do it.Don't know what sizes he uses,bloody tiny.Its a last resort to save a carb.
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Thanks for the tip. Will it be obvious which hole is the idle passage? I seem to recall there are 2 or 3 of them looking into the inlet.
 
Do you have any mates with a triple?? piece of piss to swap carbs, sure would rule them out if problem exists.
Also did I read earlier that it has the oem ignition?? Maybe time to install a modern ignition with new wires to boot! :D
Once your mates carbs are fitted and the new ignition, and problem still exists, sell it!! :D

 
motoddrob said:
Do you have any mates with a triple?? piece of piss to swap carbs, sure would rule them out if problem exists.
Also did I read earlier that it has the oem ignition?? Maybe time to install a modern ignition with new wires to boot! :D
Once your mates carbs are fitted and the new ignition, and problem still exists, sell it!! :D
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Ha, that last bit made me laugh out loud.

No mates with Triples, they are like hen's teeth - triples, not mates...........

I have just had quote from Red for his system so am considering that. I sort of like the fact that it's unmolested though - just as Laverda intended warts and all. However if some of those warts have turned septic there is more reason to upgrade.
 
Freebird said:
I have got twin vacuum gauges that I bought for my Ducatis, pretty sure I can use these as the middle carb is the datum so I can use one gauge on the middle and switch the other between the outers.
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In theory you could do that, however, one sight adjustment on one carb will affect the performance of the other: you'll be dizzy long before you've achieved a satisfactory result. See if you can borrow an extra gauge or a full set: worthwhile investment.

Also, consider using carb cleaner (aerosol) repeatedly along with some (mild) compressed air to blow the tract out. I too considered the twist drill route but bottled out! It was later i was alerted to the sticking choke cable phenomena (thanks Mo :D )

rgds
AndyW
 
Coming to this late, but valve clearances ok? Oil consumption? Compression ok? I have the red Sachse ignition with the later pickups..think Hall effect not optical.melted middle piston a few years ago because of shorting on the old pickups. These systems are not cheap though.odyssey battery seems to like the charging...don,t bother with trickle charger any more and started a first press yesterday after a couple of months sitting idle. Hope you can get this sorted.
 
The problem with dual vacuum gauges is they will work when your slides are bottomed on the idle screw but its good to do it a bit above idle as well and thats not easy to replicate from one side to the other between tests.The whole point is being accurate .Re the holes,from memory he goes in behind the mix screw after pulling it,from the air filter end and there is a tiny hole under where  the slide seats.Don't take this as Gospel,I am far from a mechanic.
 
Vince said:
The problem with dual vacuum gauges is they will work when your slides are bottomed on the idle screw but its good to do it a bit above idle as well and thats not easy to replicate from one side to the other between tests.The whole point is being accurate .Re the holes,from memory he goes in behind the mix screw after pulling it,from the air filter end and there is a tiny hole under where  the slide seats.Don't take this as Gospel,I am far from a mechanic.
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By a stroke of luck my mate was reading this over my shoulder and he's got a four way Carbtune so is going to lend it to me.
 
So, I have been working through my list and finally had that Eureka moment  :D

First I checked the compression and was very please to find all 3 within 5% of each other - phew.

Next I ran it without the middle chock cable connected - no change, so off with the carbs once again. I'm getting good at that now.

Once I found the pilot passage, my Eureka moment arrived, the middle one was blocked riight at the inlet where the diameter reduces about 3mm in. A quick twist with a 1mm diameter drill and it was clear. Rapid reassembly resulted in all three behaving in similar fashon with about 1 3/4 turns out being the fastest idle. Unscrewing them further makes no difference to the idle, which I wasn't expecting.

A 10 mile ride showed a big improvement in idle and pick up, but still not perfect. My mate forgot to bring his carbtune into work today, so balancing the carbies will have to wait until after my european jaunts.

Happy now  :D

Glen.
 
Thats good to hear,the drill bit thing isn't my idea,I just regurgitate stuff I read and hear.It comes from Will Stine,the secretary of The NSW Laverda Club.Ex Submarine Diesel Fitter and the fussiest Laverda fettle I have seen,he bought an Ultrasonic cleaning tank to do carbs but still found crap in the passages after using it.So came up with the drill bit job,its helped on a surprising amount of carbs,scary to do.Brake a bit and I expect the carb is in the bin.Same if any metal,must be done my hand and real steady
 
Vince said:
Thats good to hear,the drill bit thing isn't my idea,I just regurgitate stuff I read and hear.It comes from Will Stine,the secretary of The NSW Laverda Club.Ex Submarine Diesel Fitter and the fussiest Laverda fettle I have seen,he bought an Ultrasonic cleaning tank to do carbs but still found crap in the passages after using it.So came up with the drill bit job,its helped on a surprising amount of carbs,scary to do.Brake a bit and I expect the carb is in the bin.Same if any metal,must be done my hand and real steady
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Yes, thanks for the tip Vince. I was fortunate that the blockage was right at the mouth of the passage so no deep delving was required with the drill. 1mm is the smallest drill I've got and too big to go down the hole anyway.

Glen.
 
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