How to silence your Jota pipes?

Lothar, I bought my 80 Jota new and it was delivered to my mates bike shop in an unopened crate. I was a bit apprehensive about what I would see as I apparently bought the last 80 Jota available in Australia . So when we opened the box there was a big orange laverda with its fairing not installed and those Jota mufflers. No other mufflers were in the box , they had no stamping on them to tell you who had made them but they were definitely fitted at the factory. I think 79 Jota s that came to Australia had them fitted as standard, perhaps Red could confirm as he bought one new I believe. Maurice bought a new Jota in 81 and it definitely had the Jota pipes ex factory. Hope that helps 😀👍
Tom
 
ozijotati said:
Lothar, I bought my 80 Jota new and it was delivered to my mates bike shop in an unopened crate. I was a bit apprehensive about what I would see as I apparently bought the last 80 Jota available in Australia . So when we opened the box there was a big orange laverda with its fairing not installed and those Jota mufflers. No other mufflers were in the box , they had no stamping on them to tell you who had made them but they were definitely fitted at the factory. I think 79 Jota s that came to Australia had them fitted as standard, perhaps Red could confirm as he bought one new I believe. Maurice bought a new Jota in 81 and it definitely had the Jota pipes ex factory. Hope that helps 😀👍
Tom
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Thanks for confirming, Tom. Still I wonder how it comes, as the factory never supplied these pipes, they were a Slaters design as far as I know. The only 2 ways I could think of is that a) Slaters had their fingers on them at some point in time or b) due to special order from the Australian/Ozz importer, they were delivered from Slaters to the factory and the factory fitted them before shipment. No factory documentation I have seen so far shows them. The only documentation I know of that shows these are Slaters own advertisements or reports in the press doing road tests with Slater delivered bikes.

Maybe Piero or his son have an answer? Or JLO?
 
well - there is actually! Miguel on this forum, Steffen on the German forum etc.

My other hobby (Transaxle Porsches) show a lot (!) of young people currently showing up. almost 30% of all new registrations to the forum are people younger than 35, most of them even younger than 25! We even had a lady registering that is a professional mechanic and has restored several BMW in the past. she is 26 I believe and just purchased her first 924. Friend of mine is now 24 and bought his first 924 as a project when he was actually 16! He is now running the classic workshop of the local Porsche dealer, focussing on air cooled 911, 928 and the transaxle models!

My son - after bad experiences with his 2-stroke scooter - never wanted to ride a motor bike. this year, he got his license and with my help purchased a Ducati Monster from 2007. He can't wait to get the "open" license (currently he is limited to 48 hp) to actually ride my Formula (I thought about selling it this year but he asked me to wait until he had a chance to ride it). He also loves to drive the 944 S2 Convertible a lot. His cars are all 2004 or older.

So - there is hope actually... 😉
 
Is mid forties considered young, if so I like old bikes  :D? Well at least now my boy Louis can be considered young as he is 19 and is starting working on what will become his first Laverda 750, he doesnt know that yet, but if he finishes it, its his
 
Lothar, I imagine that a transaxle Porsche is some kind of f....ing car thing?

Young people as a whole are not interested in motorcycles the way the generation born in the 40s, 50s and early 60s is. Which is where most of us hail from.
1 of my 3 sons has a few Ducatis and Laverdas, the other two are interested in cars unfortunately though one also has a Ducati.

Of course, some young people are interested in old clonkers the same way I love bikes of the 20s and 30s. I can't really relate to the pre 1920 machines but my interest is also there.

I've said it before elsewhere, there is not very much in common between car and motorcycle amateurs apart from on certain fringes.
Motorcycles are a way of life. Being dirty, violent, into alcohol and drugs just doesn't hit with those nice people interested in cars, hotels and American Express cards.

And I'm extremely happy to see that a lot of young people are interested in neither cars nor motorcycles.

Paul
 
Definitely Jotas came in the crate from the factory with the pipes. We sold them in WA. I took an 81 Jota through rego. What surprises me is that the ADRs (Oz Design Rules) by then stipulated noise limits which is why bevel Dukes started coming with the choker Lafranconis. I don?t reckon Jota pipes could have passed but could be wrong.
 
Well I can expand on this topic a bit more, my 1981 Jota has a green low volume compliance plate riveted to the rear guard, this plate states low volume which indicates that the bike may not comply with the ADRs at the time, back in the day I would regularly flip the seat so the law could see that my bike although loud on her factory fitted mufflers was in fact legal.
 
My 81 Jota, brought new from Enzo's in Belgium, spent 2 years in Italy, shipped to Sydney from Antwerp, then sold and went to Melbourne, then finally me in Sth Oz, 40,000 k's on the clock when I bought it. Came with a very detailed and documented history. Which I still have.

I have no reason to believe that the Jota pipes fitted where not fitted from the factory or dealer.

As it is an import with no ADR/compliance plate fitted I had to have an Sth Oz  motor vehicle inspection, the exhaust noise was never an issue.
And it sounds great.

Just saying.
 
I would have thought it was only the 3CEs along with the Silver and then Gold series UK supplied Jotas which had their British made 'silencers' fitted at Slaters. After that I can't imagine why the factory wouldn't simply copy/fit them themselves to bikes destined to other markets (including the UK from '78 as I doubt the Slaters really needed/wanted to be in the exhaust procurement market...). I expect Massimo came to an 'arrangement' with the guy who designed/made the silencers for Slaters.
 
maurice turner said:
Well I can expand on this topic a bit more, my 1981 Jota has a green low volume compliance plate riveted to the rear guard, this plate states low volume which indicates that the bike may not comply with the ADRs at the time, back in the day I would regularly flip the seat so the law could see that my bike although loud on her factory fitted mufflers was in fact legal.
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... and reminds me of the time I got a ticket / fine in an old Aston Martin (straight 6) with a stock exhaust.
I took it to court (as the pipes were stock and had passed rego.) but NO .... "undue noise - manner operated".

That was Newcastle NSW and it was a cop on foot!
 
Rivot time here is some homework. Get your verniers out and measure the diameter of the hole out the back end of your muffler. I have a vague memory that there are different sized holes. My mufflers bought from Eades are stainless and have a 30mm id exit hole.
 
keep up Ron, you have not been paying attention for the last five years have you?
Jota silencers do not have any baffles, what you see is what you get, just the skin and that three inch long tailpipe in the centre of the end cap.
CLEM
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You are correct Clem I've never owned or worked on a Breganzie Triple but a Breganzie Twin is another matter ;o)

Breganzie Triples are about none existent in Ontario save for less then say 2 or 3 basket case Twins.

Breganzie Triples were mostly on the West Coast BC & Alberta some made it as far east as Winnipeg Manitoba, a few made it to Montreal Quebec.

I've seen 2 or 3 Triples round the Lake Head, just passing through, but never a Twin. Never saw another Twin campaigning Northern Ontario other then mine.

The person that bought my bike was from Winnipeg and he already owned a Triple.

Breganzies are EXTREMELY Rare in Ontario. One reason why I hide her when I parked for a coffee break at a Tim Horton's as HOG Riders swamped me if they saw saw her - Disrupting my ride for the day.

The Northern Lake Head route is very popular for American Motorcyclists Tourists - There are more Americans Motorcyclists on the road then local Motorcyclists - That is before COVID.

To say the truth. I don't care what pipes you run or how loud as long as the Carbs are jetted correctly and timing set so that you don't bog out from richness or lean out and melt pistons to reach Full Revs & Power without damaging the engine ;o)
 
If I may bring this thread back to the original point - i.e. 'how to silence your Jota pipes'. Does anyone have any good tips on an effective method? Across Europe, motorcycles are being singled out as producers of noise pollution and acoustic cameras are springing up in Switzerland, Austria, Germany, etc. I'm interested in a quick-fit set of small baffles to insert into each pipe. Doesn't have to be too efffective re. performance, just quieter, so I don't attract too much (unwelcome) attention riding in town, etc.
 
I've never actually done it, but I think I'd tackle it by making a new baffle tube. My plan would go something like this ...

1. Cut around the outlet tube in the end of the silencer. Make it a large hole so all you're left with is an internal (female?) flange around the perimeter (about 10mm wide) that you can use to fix a new baffle system onto. Remove the short "baffle" tube and chuck it in the bin.
2. Make up a new baffle tube with a flange near the end, so it looks the same externally as the original tail pipe, but has a longer tube to extend into the muffler. I reckon you'd need about a 300mm length of tube, but the length may depend on how much silencing you want to achieve.
4. Drill a heap of perforations through the inner part of the baffle tube, then wrap acoustic fibre (fibreglass mat) around the perforated tube and secure it with a further wrapping of tie wire. Obviously, it needs to fit into the hole in the end of the muffler, so don't make it too thick.
5. Insert the new baffle tube into the muffler, drill 3 or 4 holes through both the baffle flange and the 'female' flange in the end of the muffler and pop-rivet the new baffle in place.

It would look very similar to a standard Jota exhaust can. The only difference will be the end plate and fixings for the removeable baffle.

As far as I'm aware, nobody is using acoustic cameras in Australia yet. But if they're starting to be used by authorities in Europe, it'll end up here sooner or later. Such devices are way more accurate than roadside sound level meters.
 
You could start off by simply lengthening the exit tubes to the inside of the silencer. Use a pop rivet or self-tapping screw to secure a snugly-fitting tube into the exit, should knock a few dBs off the top. An even longer but perforated tube could also be quite effective, without strangling the engine too much. You just need to break up the sound waves a bit.

piet
 
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