3CL or Jota spec motor?

1200ts

1200ts

Hero member
Location
USA - Riverside CA
As spring is here, pulled out the 3CL and noticed all the minor oil leaks are getting worse. Bike is 1976 with 29,000 miles and motor has never been apart other than chain replacement. Has IIS ignition and Jota exhaust. All the seals are leaking and front of head also leaks a little oil. Nothing major, no oil dripping off bike but I suspect in another couple thousand mile it will start happening. So it time to take it apart and fix the problems.

No the question is.............. as long as I am in there should I convert the motor to Jota spec? I have never ridden a Jota and don't know anyone that has one to try riding. The 3CL was on a dyno about 10 years ago and made 72.5 HP at the back wheel. It runs very nice and jetting and ignition are spot on.

So if I bump the compression ratio and install Jota cams will I like the bike better? What kind of HP increase would I see?

Or leave the motor as a 3CL?

Bruce
 
Depends what quality of fuel is available. Hi comp pistons will make it more sensitive to octane rating and ignition settings.
While you are doing cams and pistons, what about big valves and gas flowing, then Mikunis and K&Ns?

If it runs well as is I would be tempted just to freshen it up and keep the same spec motor.
Also depends on your riding style. Jotarising it will make it harder edged and more top-endy. Maybe not conducive with your riding style?

Maybe it will suit you down to the ground though, but only you will be able to know that.
 
take it out to 80.0mm or 80.5mm pistons, will need to change liners and bore crankcase
install Ross Racing hi comp pistons in it, you can get them from Scott
run the standard A11 camshafts, don't change to 4C cams
you already have the IIS on it so it will handle the higher compression easily

bigger bore unmasks the combustion chamber nicely
you will love it, totally different engine

 
How the bike is ridden:

Used to commute to work on it 90 miles a day. Had to give that up as I was having to ride too much in the dark and the alternator would not keep the battery charged. Now with the IIS that's not a problem. Currently it's only a Sunday bike. The wife is on the back perhaps 30% of the time and I am not allowed to go over 80mph or I get poked in the back, OUCH!

The rest of the rides are with friends on more modern bikes. Its fun to show them what a 35 year old bike can do when ridden in anger. And they comment a 180 Laverda at full throttle sounds like no other motorcycle ever. It's get ridden much more than my gay 120's.

Its also fun to pass younger riders on brand new Japanese bikes who can't ride worth a shit. Almost all of them have never seen or heard of Laverda.

Red,

I like you idea of the big bore and A11 cams. Although the 3CL is a lot faster than my 1200TS which also has IIS and Jota exhaust. Perhaps the 1200TS cams are the problem?

Bruce
 
Bruce, I like Reds suggestion of A11 cams and higher compression but you dont need to go to 1200 to feel the benefits. My old 3C ran Jota pistons and A11's and was a lovely responsive sharp motor. Probably didn't have the top end but I didn't miss that because it was so good elsewhere. Regards Pat.
p.s. 1200 would be torquey though  :D
 
Just be careful poking at the hotup disease,it gets expensive faster than the bike ends up,he says waiting for a F1 cam converted to 180 spec,I got it bad.But having them come on song feels so good
 
I won't get into the triple modding discussion, being a twinner and all.
Grant hit the nail on the head. It all depends what you want to ride.
I was many years a mechanic in dodgy Italian bike workshops  :-X and often had people ask the same question.
The bike had got tired as they got used to it and they thought it was time for a "hot up".
Unless they really did want a lot of power I advised freshening it up standard and "blueprinting" cam spec, comp ratio etc for it to be as good as it can be. They were never disappointed. The bike didn't need sorting out and they never wondered if it was as good as it could be. Taking the suspension at the same time was icing on the cake.
I've test ridden and borrowed most every model Lav except Zanes, they are all with their charms.
 
You must log in or register to reply here.
Back
Top