Laverda triple right cylinder not getting hot

Reino

Reino

New member
Location
Bunbury, Western Australia
Hi all,

I have been working on one of my Laverdas lately, it is a 1977 3CL.
I believe I may have an issue that I can't seem to shake. The right side cylinder is not getting anywhere near as hot as the centre and left cylinders.
I have thrown multiple sets of plugs at it B8ES
I have rebuilt and ultrasonic cleaned the carbys Dellorto PHF32's, new fuel line, fuel filters, etc.
It is sparking well when I pull the plug to check it, and the carby seems to be functioning correctly as well. Compression is more or less the same across the three cylinders.
Any ideas what else could be going on?
 
Reino said:
Hi all,

I have been working on one of my Laverdas lately, it is a 1977 3CL.
I believe I may have an issue that I can't seem to shake. The right side cylinder is not getting anywhere near as hot as the centre and left cylinders.
I have thrown multiple sets of plugs at it B8ES
I have rebuilt and ultrasonic cleaned the carbys Dellorto PHF32's, new fuel line, fuel filters, etc.
It is sparking well when I pull the plug to check it, and the carby seems to be functioning correctly as well. Compression is more or less the same across the three cylinders.
Any ideas what else could be going on?
Click to expand...
Could be a number of things, what type of ignition do you have.
 
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Sorry no input regarding the problem but if you get it going soon I'm booking a 2 day track event at the Collie Motoplex 17-128th Feb.
Be a good chance to give your triple a good flogging, maybe all it needs. I know that my triple benefits from one.
Also hoping there'll be a couple of other laverdas turning up as well. Having said that it sounds like a good idea at the time but come that weekend we'll see who turns up. I'll be there as it's the best fun I have riding my triple in the way they were design for.
I'm in Walpole
 
motoddrob said:
Sorry no input regarding the problem but if you get it going soon I'm booking a 2 day track event at the Collie Motoplex 17-128th Feb.
Be a good chance to give your triple a good flogging, maybe all it needs. I know that my triple benefits from one.
Also hoping there'll be a couple of other laverdas turning up as well. Having said that it sounds like a good idea at the time but come that weekend we'll see who turns up. I'll be there as it's the best fun I have riding my triple in the way they were design for.
I'm in Walpole
Click to expand...
Thanks mate I will see if I can make it for sure bike or not I'd definitely like to come along.
 
Yes please do. I'd love to see a few more classic bikes on track otherwise it's my Laverda amongst a group of Jap pocket rocket track bikes with a few 90s Ducati 900ss thrown in. Doesn't anybody ride their bevel Ducatis anymore.
 
That kind of odd, spark fuel compression = power. Did this suddenly happen, has it run well before? Has it sat for a while? Is the carb slide working on that cylinder, try swapping the spark leads between 1 and 3 and see if that changes anything.
 
Vince said:
That kind of odd, spark fuel compression = power. Did this suddenly happen, has it run well before? Has it sat for a while? Is the carb slide working on that cylinder, try swapping the spark leads between 1 and 3 and see if that changes anything.
Click to expand...
Yeah kind of what I was thinking. Yes it sat for a while, carb slide is working. I will give it a go shortly and I'll also be able to answer what ignition it is to everyone else because it has completely slipped my mind.
 
Vince said:
try swapping the spark leads between 1 and 3 and see if that changes anything.
Click to expand...
This would be a good test. Maybe a bad suppressor cap/ ht connection?
Another check is the enricher.
Having said that, my 120 runs like a sack of wet arseholes when it drops a pot, you haven’t said it isn’t running right, presume that’s the case?
 
Andy said:
This would be a good test. Maybe a bad suppressor cap/ ht connection?
Another check is the enricher.
Having said that, my 120 runs like a sack of wet arseholes when it drops a pot, you haven’t said it isn’t running right, presume that’s the case?
Click to expand...
Swapped them over and no difference, forgot to check what ignition it is so i will have to go back and check.
It's running OK not perfect, not bad, but OK. Much prefers to be run on choke as it is though.
It's definitely firing on the right side but noticeably far less temperature on the exhaust From the right side than the other 2.
Thinking I might have to rip off the cover and check valve clearance again.
 
Centre header is straw in colour, the outer two are somewhat similar brighter chrome, perhaps some discolouring or reflection from the tank colour, for the outer two. See a stray wire on the right side hanging down? Straw can mean hotter on the centre, if your using it as a reference against the outer headers.

How are you evaluating the actual temperatures of the headers ( most obvious place to assess ), plug chop would be next, though if down in power on one cylinder it becomes very obvious, if not somewhat dangerous to ride.

Digital IR Thermal laser point devices are low cost, you should see around 440+ degress C at the first bend on each header. Contact thermo couple is also valid, what i use here, when required. Note your running 3 into 1, a road of much varying performance, as an aside.

Need actual reading from the place your measuring, to be precise, as it stands, broad guessing competition. One of the more obscure aspects may well be that what you have been working on is not the problem, meant with genuine pertinence, sometimes you can alter something and it makes it worse, which is good, means that is the area which may be the root cause.

To my uncertain knowledge, a variant i did with iis was the only true triple fire 180 ignition, ie 3 single tower coils fired as three coils, not a stacked coil primaries on the outer two. Most probable you have a BTZ, Witt or.... guessing again.... then if you have a HKZ, you can have a feeble spark on one outer cylinder as the mini coils fire in series on the outer cylinders though different secondary HT output, rare though as the HKZ coils are very well made, bosch engineers did a good job without the sales/accoutant turkies getting involved... sometimes...HTH j
 
I believe you inherited the bike? If use back in the late 80s early 90s there was a laverda mechanic in Perth who had some strange ideas. One was to fit a bigger main jet in the middle carb. So worth checking the main jet sizes.
Not that it is the cause of your issues
 
Reino said:
Swapped them over and no difference, forgot to check what ignition it is so i will have to go back and check.
It's running OK not perfect, not bad, but OK. Much prefers to be run on choke as it is though.
It's definitely firing on the right side but noticeably far less temperature on the exhaust From the right side than the other 2.
Thinking I might have to rip off the cover and check valve clearance again.
Click to expand...
Easy things first, what was the compression readings? This mov is not good from yesterday, and yes i ran the engine backwards for the sharp of eye, grin. Why is this so? j
 

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