Hello all - Newbie Laverda owner

JO55

JO55

Full member
Location
Cornwall
Hi All,
I just wanted to say hello having recently joined the forum and the ranks of Laverda ownership.

Having been a lifelong off road racer (MX and Enduro) and 80's two stroke fan, Laverda ownership has eluded me - although I do have a Laverda fan friend who races his 2 Husqvarna based MXers at some of the classic meets we do (my weapon of choice is a '81 KTM495). However, I have always had an eye on the Jota and had a secret hankering for one, a hankering that I've recently been able to realise, having bought a fully restored '79 model.
I have already realised that they are motorcycles of great "character" and had lots of fun when I inadvertently gave her way too much choke, resulting in some seriously fouled plugs! I'm sure I will have lots of questions in time, but for now have 2.

1/ stationary, once started cold, she struggles to idle and pick up is laboured with the odd cough and splutter. Once going, it feels like shes massively restricted, almost like she's firing on 2 cylinders. Then randomly about 5 minutes into the ride, she clears her throat, the induction roar becomes hugely more pronounced and suddenly, she's a rocket ship. This continues for about 10 minutes and then shes will go back the restricted feel. It's almost like a 'limp mode' on a modern car. When shes going, she feels great and revs cleanly right through the indicated red. Any ideas would be appreciated.
2/ This leads me on to issue 2. Yesterday (I've only been out twice on her), when cleared, i gave her a good blast. When I got home, I was horrified to see oil splashed down the righthand side of the bike and rear tyre. I assumed a leak, but on closer inspection, it proved to be the crankcase breather pipe - nicely positioned to spew oil all over the rear tyre! With the bike being new to me, I suspect it might be that someone has overfilled the engine and that she's just throwing out the excess. Is this a known thing, and if so, is there a catch tank available that people use as the consequences of this happening on a fast right-hander don't bare thinking about?

Thanks in advance for any help on this and if there are any other pearls of wisdom (Laverda related!) you have, I'd love to hear them.

Cheers
 
Your carbs could have some  rubbish in- drop the float bowls - check the flow of the petrol taps in case there is rubbish in the tank - really the DOs need a strip down if it hadn?t been
Done recently
 
Oil level is set with the bike level and the dipstick also vertical and just sitting on the threads. The only time my bike spat oil out the breather was a month after I bought it with apparently a just rebuild engine. The idiot who thought he could do that changed the inlet valve oil seal leaving the warn out guides, that lets compression gasses get into the crankcase and pressurising it. Do a compression test. What ignition is in it, who fully restored the bike. Good luck on getting it running well. Post a pic if you can. That KTM must be fun, in a scary way
 
...on the oil front, my 79 Jota will do that if revved hard..frankly the best solution is not to fill to capacity. Of course this could be an indicator of wear and hence increased crank case pressure, but try draining the oil and putting less in, though not too little!
Have always wondered how the racers back in the day, and indeed now deal with this?
 
Sorry, I'm not sure how, or if you can reply to specific replies?
Thanks for your welcome and advice so far chaps. I should say that the bike had an extensive engine (and infact, entire bike)rebuild at Windy Corner Laverda dealers. However, this was back in 1987. I have receipts for all the work done and she's done 5000 miles since, so, I'd hope that nothing is worn yet. Seals hardening would be a worry though?
@Sir Sidney - I should have said, I've had the carbs off, cleaned them (there wasn't much muck anyway) and set the choke and throttle slide heights. Also replaced all plugs with a hotter grade (B7ES) due to my previous fouling issue.
@Vince - Ignition is BTZ Bosch. I'd hope, but can't be sure, that the rebuild was done correctly as it was an official dealer. I did rev her pretty hard for a bit, so it's feasible that if the oil is too high, it could come out.
Yes, I'd say that it's more scary in a fun way! To this day, still the fastest ever standard dirt bike when geared up on a salt flat in the US. It hit 123.7mph in '81. No standard dirt bike has bettered it since!
@Nick7 - Thanks - it's only done 5k miles since full rebuild so should be OK. That said, it's new to me so I don'y know how she's been treated. I think a lot of racers put a catch tank on the end to stop the breather throwing oil everywhere. I'm probably going to do this, as I don't want a repeat.

Thanks guys, much appreciated
 
Have always wondered how the racers back in the day, and indeed now deal with this?
 
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A catch tank is obligatory in Uk racing (and probably everywhere). I also add another breather to the cambox on the triples and, on the 750's one on top of the gearbox casting. I use a "Morini 3?" breather baffle in the added tubes. Don't fill oil right to top of level marks. - Regards - Phil
 

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If it has only done 5k since 1987 it has obviously been sitting a lot. Depending on the atmosphere it could have some bore rust, not knowing how it was broken in, you could be dealing with a ring sealing problem. If it was mine I would run it fairly hard for a while and see if the blow by  decreases and the bike runs any better. Another item to check would be the valve clearances just to be sure nothing is too tight. Another concern would be the insulation falling off the Bosch ign. pickup wires, very common and isn't dependent on how it has been used.
 
Agree with Phil , B7 plugs too warm, at least put B8 in, should run well on B9 ?

Check the oil level. From experience over filled sumps tend to cause oil seals to blow first.

Yes , while trying sort problem I'd put a catch 'tank' bottle on end of breather for safety.

If oil level OK , and still blowing, my money is on ....................... well lets not go there for the time being!

Andy
 
Carbs certainly dirty, rings gummed up at the best, rusty bores at the worst.
Is it smoking?

Engine should be treated as if it had just been rebuilt after a lay up like that. Did you squirt oil all over cams and buckets before starting it up?

Paul
 
If it's still on the same jets as in 1987, it'll be running rich. Check what size pilots and mains are in it.
I know on mine I've come back two sizes.
I don't know the chemistry of it but modern fuel needs smaller jets than the stuff we used when the bikes were new did.

 
Agree with diagnosis by wdietz186 & Paul - my engine spewed oil out of the breather when an oil control piston ring broke.  Running in on semi or fully synthetic oil is not recommended if you want to avoid glazed bore and smokey exhaust. Would be worth doing a compression / leakdown check, as well as the basics previously mentioned like checking the oil level is correct.  ::)

And as Phil and Andy have said, change the plugs back to B8ES.  Starting procedure - apply full choke and be ready to back off to half as the engine fires.  Push choke fully off usually within 10-20 secs. A BTZ equipped bike will suffer cold fouling so don't start the bike up without riding it off.  Failing pickup insulation - or BTZ box - not unheard of at this age. 

How's the battery and earth connections?

How did you 'set the choke and throttle slide heights'? Vacuum gauges are needed to balance the carbs properly. Choke cables just need to have slack in them when in the off position.
 
Take the 7 spark plugs out they are too hot for that engine. Hot plugs will not fix your problem.
Compared to modern carbs Dell's are not as efficient and can seem to over fuel, check float heights and jet sizes, depending on the fuel available you should be able to get away with 55 pilots and 125 mains but there is a whole lot of other stuff you need to check prior to jet sizes.
If your engine is tight there should be no oil blowing out of the breather at all.
check the level with the dip stick dropped in the hole sitting vertical, the oil level should be between the two marks.
 
phil37 said:
Bit risky IMHO unless just pootling around town - regards - Phil
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Yes, I think I will put it back to 8's. It's probably more, to do with my education of how to use the choke, combined with new plugs (any new plugs) that has got her going and not fouling.

That's quite a breather set up you have there. I will definitely fit some sort of catch tank while I sort the issue out. It does appear to have rather a lot of oil in it going by the vertical dip stick method. There are 3 indents in the stick, the level is at the end of the last one, so I'm guessing right at the highest of point of the permitted range.

Thanks
 
maurice turner said:
Take the 7 spark plugs out they are too hot for that engine. Hot plugs will not fix your problem.
Compared to modern carbs Dell's are not as efficient and can seem to over fuel, check float heights and jet sizes, depending on the fuel available you should be able to get away with 55 pilots and 125 mains but there is a whole lot of other stuff you need to check prior to jet sizes.
If your engine is tight there should be no oil blowing out of the breather at all.
check the level with the dip stick dropped in the hole sitting vertical, the oil level should be between the two marks.
Click to expand...
Thanks, I'll swap them out no I know the correct choke ritual!
From memory (I should have wrote it down while they were out), it has 55 pilots and 145 mains - it appears to be running with the airbox, but no filter though, but I have no idea how long. As an off roader, this fills me with dread, so will change before I do any serious riding, which will necessitate smaller mains anyway i imagine.
I think the oil was too high - crosses fingers!
 
phil37 said:
A catch tank is obligatory in Uk racing (and probably everywhere). I also add another breather to the cambox on the triples and, on the 750's one on top of the gearbox casting. I use a "Morini 3?" breather baffle in the added tubes. Don't fill oil right to top of level marks. - Regards - Phil
Click to expand...
Firstly, thanks for your advice, and, 'not going there'! On checking via the correct method, the oil level does appear to be high, but only within the range on the stick (top end of the 3 indents). From what people have said, that could be enough to cause it. I will put a catch tank of sorts on there.
 
Paul Marx said:
Carbs certainly dirty, rings gummed up at the best, rusty bores at the worst.
Is it smoking?

Engine should be treated as if it had just been rebuilt after a lay up like that. Did you squirt oil all over cams and buckets before starting it up?

Paul
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Thanks Paul,

It's been run frequently, but only been ridden occasionally. I'm thinking this probably wouldn't be required. No, absolutely no smoke at all and sounds sweet.
 
Ernesto said:
Did you check float heights? 18mm +/- 0,5mm on PHFs.

Ernesto
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Thanks.
No, I didn't, although I should have. It doesn't feel like a float height issue, or even a fuel issue I would say. The reason I say this is because it's like it from cold (when a fuel starvation issue wouldn't normally occur, and it clears as you ride, when the former issue would normally happen - although, it does return again so ....

It feels more like electrical as it's as if a switch has been turned on.
 
Vince said:
Oil level is set with the bike level and the dipstick also vertical and just sitting on the threads. The only time my bike spat oil out the breather was a month after I bought it with apparently a just rebuild engine. The idiot who thought he could do that changed the inlet valve oil seal leaving the warn out guides, that lets compression gasses get into the crankcase and pressurising it. Do a compression test. What ignition is in it, who fully restored the bike. Good luck on getting it running well. Post a pic if you can. That KTM must be fun, in a scary way
Click to expand...
Sussed how to answer directly now! thanks for your help.

I'd post a pic, but can't for the life of me see how to?
 
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