David_Jones
New member
- Location
- UK
Hello, can anyone recommend a quality gasket set make and supplier for a Laverda Jota 1979? I gave seen the Athena make on ebay are they any good? Regards, David Jones
1979 Jota gasket set
- Thread starter David_Jones
- Start date
In the UK, get your gaskets from Phil Todd who's on here somewhere.
Most people use Athena but buy them from Athena, why ebay?
Paul
Alexb83
Full member
- Location
- Northumberland
Probably because if you go on the Athena website and search under Laverda Jota, they dont show a gasket kits, just out of stock brake pads and some silicone sealant recommendations.
Whereas the kits are lined up on ebay if you google.
Strangely, yes. But if you google individual gaskets, they turn up directly at Athena.
Otherwise plenty of shops doing them.
For example:
Pochette de joints moteur complète ATHENA - LAVERDA
3AS Racing vous propose le Pochette de joints moteur complète ATHENA - LAVERDA, profitez d'un transport en 24h en choisissant chronopost, ou d'un paiement en plusieurs fois.
You might want to try contacting Keith at Laverda Scozia to see if he'll sell you one of his improved head gaskets with copper inserts around the oilways rather than the O rings.
Paul
David_Jones
New member
- Location
- UK
Thanks for the information. Does any one know why there are two cylinder base gaskets in the Athena pic?
The Sock
Hero member
- Location
- London, England
For 1000cc and 1200 ( 1117cc) motors. Different diameter liners externally and hence Different base gaskets. I believe std thickness here is 1mm composite, so it should be clear somewhere the diference. If you look at the cylinder pull down stud holes, you can see they're closer to the liner hole on 1200 base gasket.
Head gaskets remain the same for both motors but be aware Athena offer 1, 1.2 and 1.5mm thickness so be mindful what you get if you go that route. They all have specific part numbers. Again std is 1.00mm, thicker are to compensate for skimmed barrels/head.
Just vernier what you took out if it was running well.
Dont forget the 4 viton O rings, they are not always included with individual gaskets.
Rob
Last edited:
piranha-bro2
Hero member
- Location
- Melbourne
I'm surprised to read that - how do they deal with the flame ring and the different bore size? Going from 80mm to 87mm on a twin definitely requires a different head gasket.
Not doubting, just curious.
Piet did a post on this a while back, someone made a change to their headgasket design to reduce inventory without announcing it, and it bit a few people in the arse. It's well worth searching out the details. I like Keith's design idea. And the usual gaskets Phil does are top-notch.
motoddrob
Hero member
- Location
- S/W Australia
Q, 75mm bore liner has a raised spigot that sits in the reset on the head.
80mm bore doesnt have that spigot so the mating surface is flush.
Standard gasket fits both.
That tells me that spigot must be 2.5mm thick.
80mm bore doesnt have that spigot so the mating surface is flush.
Standard gasket fits both.
That tells me that spigot must be 2.5mm thick.
Fuckin' Sherlock!
Only item missing to answer following questions is that the pistons have different compression heights to compensate the different effective liner length, ie, the 1200 piston is 3mm shorter.
piet
motoddrob
Hero member
- Location
- S/W Australia
Didn't want to get into too much detail otherwise Q might've got confused!
To be honest I didn't know that about the pistons. Only ever worked on my 1200 but have assembled a couple of 1000s in the past.
To be honest I didn't know that about the pistons. Only ever worked on my 1200 but have assembled a couple of 1000s in the past.
piranha-bro2
Hero member
- Location
- Melbourne
Yeah! I confuse easy! 
If the spigot fits into the chamber skull then couldn't the 1200 piston just take its place and protrude into the skull without being shortened that 3mm? What shape and height at the swish does a high comp 1200 piston have?
If the spigot fits into the chamber skull then couldn't the 1200 piston just take its place and protrude into the skull without being shortened that 3mm? What shape and height at the swish does a high comp 1200 piston have?
Too much compression Quentin!Yeah! I confuse easy!
If the spigot fits into the chamber skull then couldn't the 1200 piston just take its place and protrude into the skull without being shortened that 3mm? What shape and height at the swish does a high comp 1200 piston have?
Shouldn't underestimate what an additional 5mm bore does to CR. Stock 1200 slug has a flat top, resulting in 8:1. The aftermarket hi-comp 1200 piston domes are quite similar to the Jota 1000 pistons. Not much needed to bump the CR by a couple of points. The 1200 was meant to be for gents, not hoons.
Ideally, a piston will not protrude past the end of the liner, gives the top ring an even harder time than it already has.
Besides, if Laverda hadn't gone this route, I would have had to look elsewhere for my long-stoke 750... or probably wouldn't have had such a daft idea in the first place! The flat-top 1200 piston upped CR considerably with the additional 6mm stroke compared to the stock set up, turned into a bit of a nightmare dialling all that in to avoid pre-ignition etc. Not sure it would have worked with conventional domed pistons, at least not while retaining its manners.
piet
piranha-bro2
Hero member
- Location
- Melbourne
Probably why the smart arse prick on the XS1100 gave me the middle finger as he went past on the straight in the '78 Castrol 4 Hour!! I think the opposition had heard about this TWELVE HUNDRED LaverdaThe 1200 was meant to be for gents, not hoons.
piet
and were a little concerned ... until they saw the real thing in action. Might have been a different story if the shop had had access to a Jota. It's history now.Very interesting journey to build that long stroke GTL, Piet!!