Laverda triple right cylinder not getting hot

Is that dry? Very high if so, and sort of low if the comp test was done wet. May well be the type of gauge you have there, 165 is the best i have seen dry on Ross or JE pistons. Around 220 wet. Re-read your posts, not making a lot of ( my ) real world sense, conundrum as it were. j
 
motoddrob said:
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
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That was quite common practice, not just in Perth.
Paul
 
iis_iis said:
Is that dry? Very high if so, and sort of low if the comp test was done wet. May well be the type of gauge you have there, 165 is the best i have seen dry on Ross or JE pistons. Around 220 wet. Re-read your posts, not making a lot of ( my ) real world sense, conundrum as it were. j
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Yes dry, no idea on the type of gauge it's older than the bike. Most of my tools live on site as I am a diesel mechanic and have limited/less quality tools at home.

Not sure what isn't making sense though in the way of my posts?
The whole situation isn't really making sense to me as fuel/air/compression = Power.
I am welcoming any criticism etc, as I don't have much experience with these older bikes I did a few years of small motors but mainly single cylinder engines and nothing of the age etc.
Had a look at the ignition seems to be a BTZ.
Unfortunately I have no idea on the history of the bike. It was an inheritance. All I can see that it was very handy man work etc done, like parts held together with wire etc.
 
Best check the headers with a proper temperature measuring gadget, remote handheld gadget with a Lazer. I don't remember their name but they're more accurate than licking a finger and touching a header. In my world headers are either too hot to touch or cold. Not sure how one notices slightly less hot, blue colour may be an indication of different combustion temps. There have been cases of one cylinder not advancing with revs, that's worth investigating with a timing light. The original ignition was notorious for only having one sudden jump to full advance at about 2 and a bit thousand revs.
 
Sounds a bit like fuel starvation on that pot?......if it prefers to run better on choke as you say,worth checking (blowing through) the pilot system sometimes dirt can get dislodged during the cleaning process.......good luck.
 
stop faffing around , take the carb bank off and swap the right carb with either of the other two, if the fault "moves with the carb" you have found it, this makes getting at the pilot adjuster screw hard, but you can revert once sorted.
CLEM
 
Reino, being a diesel mechanic then EGT is no mystery to you. Makes for less of the unknowns sorting issues by remote control, when the owner has skills above usual. Would still have accurate temps for the cylinders, before disturbing anything major, did note what you had done prior, hence my "does not make sense" indication, all faults make sense in the end.

Ruled out first up an ignition issue as broad view, given the outer two cylinders are series fired on the HT side, ie lead or plug cover are in series, effect one cylinder effect the other, apart from a shorted or partial leaking plug on one cylinder. HTH j.
 
Got me there Chris, when i first viewed the clip, had to doubt myself as to double check in my mind was the crank going in the correct direction... stop frame effect on the ipad camera does play tricks with what seems obvious and what is actual. j
 
CLEMTOG said:
stop faffing around , take the carb bank off and swap the right carb with either of the other two, if the fault "moves with the carb" you have found it, this makes getting at the pilot adjuster screw hard, but you can revert once sorted.
CLEM
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Do what Clem said and if it's not a carb issue maybe someone in your region can loan you a BTZ ignition. I chased a similar problem for weeks, the bike was running OK not good, and yes at times one pot was not firing as it should, so the pipe was cooler Problem was the HT leads were not making secure contact with the coil connection. Maybe before you pull the carbs for a swap check the HT leads on the coils. Good luck.
 
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...

The pilot jet passageway may be restricted?
 
Hi all, Just for some clarification, i pulled all 3 carbys off and bench tested them again. I found one carby is not functioning correctly, which is odd seeing as they all bench tested great after I rebuilt them. Anyway I will send another update once the rebuild kit arrives and I rebuild it again.
Cheers for the input
 
Just a double check that all needles are definitely clear and I can see through them. And then to check all seals etc. I made A stand with some expanding rubber bungs that seal and hold the carbys on. Hook fuel up, check for leaks, blow through and make sure fuel is coming through
 
In that case, check the pilot circuits are clear with carb cleaner aerosol... how to in the library

Extract here -
PILOT BLOCKAGES. The easy way to check the progression galleries with carbs built
and on the bike is remove pilot jets and mixture screws. Open the throttle. Use a
can of carb cleaner with extension tube fitted. Put the tube up the hole where the
pilot jet goes; cover the mixture screw hole with finger and squirt cleaner while
looking for a stream coming up into the venturi, just in front of the back edge of the
slide. Then put the tube in the mixture screw hole, cover the pilot jet hole with
finger and squirt cleaner whilst looking for a stream coming out between the slide
and the engine. Finally put the tube into the little air hole under the carb intake (not
the "middle" one - the other drilling) Squirt and look for cleaner in the venturi.
 
Rob said:
In that case, check the pilot circuits are clear with carb cleaner aerosol... how to in the library

Extract here -
PILOT BLOCKAGES. The easy way to check the progression galleries with carbs built
and on the bike is remove pilot jets and mixture screws. Open the throttle. Use a
can of carb cleaner with extension tube fitted. Put the tube up the hole where the
pilot jet goes; cover the mixture screw hole with finger and squirt cleaner while
looking for a stream coming up into the venturi, just in front of the back edge of the
slide. Then put the tube in the mixture screw hole, cover the pilot jet hole with
finger and squirt cleaner whilst looking for a stream coming out between the slide
and the engine. Finally put the tube into the little air hole under the carb intake (not
the "middle" one - the other drilling) Squirt and look for cleaner in the venturi.
Click to expand...
Thanks for that I will double check.
I was sure that I had sprayed through these passages and checked flow but it never hurts to try again.
I was originally thinking that I may have mucked up the fuel hose routing as I still am currently unable to find exactly how they should be plumbed up. All bowls were filling though so I gave up on that theory.

It is the only carby I didn't replace the diaphragm in as I was missing one from my order and it had the best one on it so I let it be. But I have ordered a full new rebuild kit for it again jets and all as any spares I have can be used on the next bike.
 
Reino said:
Thanks for that I will double check.
I was sure that I had sprayed through these passages and checked flow but it never hurts to try again.
I was originally thinking that I may have mucked up the fuel hose routing as I still am currently unable to find exactly how they should be plumbed up. All bowls were filling though so I gave up on that theory.

It is the only carby I didn't replace the diaphragm in as I was missing one from my order and it had the best one on it so I let it be. But I have ordered a full new rebuild kit for it again jets and all as any spares I have can be used on the next bike.
Click to expand...
Forget the pumpers.
Paul
 
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