LCGB Forums

The ability to post messages is restricted to LCGB members. Any questions contact us at lcgbadmin@googlemail.com

Changing to clubman exhaust

Technical help for Series one, two and three Lambrettas. Models include the Li, Li Special, TV, SX, GP, Serveta and API/SIL models

Re: Changing to clubman exhaust

Postby Warkton Tornado No.1 » Fri Jul 03, 2020 1:52 pm

Danbretta wrote:Yours looks ok,the only real difference I can see is your inlet and main bracket have been welded differently. I see yours is the later version without the mushroom baffle and the addition of the extra support bracket.

The original one that I took off my 1964 LiS doesnt have the mushroom baffle or extra support. I dont' know if it was original to the bike or changed during its life in Italy.

I dont know if there is much of a difference having this mushroom baffle or not, maybe there was if it was dropped on the later exhausts. Does any one know?

How's the paintwork on the scootopia one, does it scuff or come off easy? Im undecided whether to strip mine back to bare metal to repaint in the ceramic paint or try going over the paint alread yon there, the durability will only be as good as the base layer. It's that old scenario of giving myself more work than I need to or finding out later I should have done a proper job when i had the option..


Quite a dilemma, as the OEM exhausts burned off the paint on the 'U' pipe, so anything more durable will be not as intended. Which is a shame considering the detail of the replicas discussed.

Hmmm. I have amongst my collection of exhausts, an expansion chamber from a 'crosser that is electroless nickel plated. My belief is that coating is extremely durable, considering the harsh environment it is intended for.

I also have an original Ancilotti (50 mm) that I got some kind of baked on finish applied to in the 70's. It still survives on the 'box but the 'U' pipe temperature will see off any finish IMHO so when in use, I just keep applying oil to let it bake on......Otherwise, I'm very environmentally friendly, honest! :oops:
Warkton Tornado No.1
 
Posts: 1588
Joined: Sun Jan 11, 2015 1:27 pm

Re: Changing to clubman exhaust

Postby Storkfoot » Fri Jul 03, 2020 4:32 pm

In my experience, no paints and powder coats last long on our wet and salty roads. I have never lashed out on a ceramic coating like Vegansydney refers to. I have been tempted to, but I tend to think that all exhausts have a finite shelf life, and so, it’s not really worth it. Having said that, in my case, I am pushing the boat out and getting the ubend chromed, which is a first for me :D

If I was you, I’d leave the paint as it is as you would assume that Tutto did at least bake it on. I’d just VHT spray the bit they missed, especially if the clamp does not fit in that position.

Yes, my Scootopia exhaust is the later GP variety without a mushroom shaped baffle. I am no exhaust expert but the baffles were to reduce noise and provide back pressure. Knocking them out allows the exhaust to move air quicker but won’t necessarily give your scooter more speed or torque. That said, the late SX and GP Models did not have baffles in that position and were sportier engines than had come before. I would trust Innocenti’s engineers to have concluded that there was a benefit in removing them although whether they did any other tweaks to the silencer at the same time, I don’t know.
User avatar
Storkfoot
 
Posts: 1213
Joined: Fri May 30, 2014 8:59 pm
Location: Merseyside

Re: Changing to clubman exhaust

Postby shane BBoys » Fri Jul 03, 2020 4:49 pm

I had an old NK on my TS Jet that was ceramic coated it was shit and did not las 6 months, never again I’ll paint my own ta!
Cheers Shane.
User avatar
shane BBoys
 
Posts: 380
Joined: Sat Sep 06, 2014 5:46 pm
Location: Bradford

Re: Changing to clubman exhaust

Postby Warkton Tornado No.1 » Fri Jul 03, 2020 6:58 pm

New OEM type exhausts are a lot like new shoes. The first time you wear them outside, you 'ruin' the soles ;)

Unless an exhaust is fitted for a show only type machine, you just have to accept that it's surface finish will deteriorate.

I suspect that like many others, painting them in BBQ paint & just keeping an eye on them is only a part of a maintenance routine that we accept.

My belief is that a standard exhaust will run much hotter as it's design is restrictive. Maintaining free flowing expansion chambers is far easier.

As for the mushroom baffle, then that will be alright on any of the earlier engines, but the later, revised engines will be restricted. Horses for courses, but a free flowing exhaust does allow for an amount of over-rev which broadens the engine's range, even when standard, as I found with a GP150.
Warkton Tornado No.1
 
Posts: 1588
Joined: Sun Jan 11, 2015 1:27 pm

Re: Changing to clubman exhaust

Postby Danbretta » Fri Jul 03, 2020 8:54 pm

So adding the mushroom baffler in reduced the noise (I get that) but what does back pressure do, what would the benefit of that be on an engine (sorry for sounding dumb, this is all new to me and interesting to learn, got to learn somewhere right?). What was changed on the SX150 to make Innocenti remove the baffle?

I have a 150 silver special and the clover leaf exhaust doeant have the mushroom or the extra bracket (under engine). What model would this originally come from presuming it isnt original to the engine? Was the special just a change in appearance using TV styled parts or was much done to the engine to improve it over the standard Li150?

Tuttos website lists the following Li125, Li150, Li125S and Li150S under the same exhaust while TV175, SX150 and DL150 using the later exhaust (this is purely by going by the their part numbers on the website)

I did notice when putting the barrel back on that the inlet manifold was stamped 175, would this be an owner upgrade from a TV175 or is the stamp a tool number?
Danbretta
 
Posts: 136
Joined: Tue Jan 03, 2017 2:05 pm

Re: Changing to clubman exhaust

Postby Storkfoot » Sat Jul 04, 2020 2:27 pm

Wow. Lots of questions there, mate :D

Back pressure. I suggest you spend half an hour doing searches on the workings of a two stroke engine/exhaust. Then, if you are like me, you’ll have a basic layman’s understanding of how the engine, in particular the carb and exhaust, work in tandem.

As for your other questions, I’ll leave that to others although I believe the extra exhaust bracket underneath the casing emanates from when the early TV200 silencers started rattling themselves to bits.
User avatar
Storkfoot
 
Posts: 1213
Joined: Fri May 30, 2014 8:59 pm
Location: Merseyside

Re: Changing to clubman exhaust

Postby Danbretta » Sat Jul 04, 2020 5:49 pm

Did some trawling on the internet last night and got the gist of it now, thanks. Makes sense to me know I understand it.
Danbretta
 
Posts: 136
Joined: Tue Jan 03, 2017 2:05 pm

Re: Changing to clubman exhaust

Postby Warkton Tornado No.1 » Sat Jul 04, 2020 6:06 pm

I think that the best way of understanding exhaust technology from back in the 60''s is to be aware that until that time, four strokes were still seen as the pinnacle of engine development.

Consequently, to a great extent, those manufacturers of two wheeled machines were mass producing two-strokes as a cheap engine for which little in the way of performance was truly anticipated.

Look @ Lambretta's own 'V' twin racer for which the natural choice was to use a four stroke engine.

It was when technology moved forward via the East Germans/Japanese that two stroke engines came to the fore. The key to the release of such huge power hikes was the expansion chamber. Principally, the expansion chamber functions to give a supercharging effect, any noise control then being dealt with downstream via the exhaust bleed (tailpipe)

So, the two schools of thought with a naturally aspirated two stroke engine are to have developed either an exhaust that harnesses the best characteristics of a two stroke engine via an expansion chamber or to use the space available to construct a maze of baffles & other methods by which to quieten down the expelled gases.

Both methods have their advantages & disadvantages. Notably, the traditional box exhaust is often advocated as a means of ensuring an engine endowed with low down torque, which is fine if that is best suited to a particular machine or driver.
Warkton Tornado No.1
 
Posts: 1588
Joined: Sun Jan 11, 2015 1:27 pm

Re: Changing to clubman exhaust

Postby vegansydney » Tue Jul 07, 2020 1:06 am

shane BBoys wrote:I had an old NK on my TS Jet that was ceramic coated it was shit and did not las 6 months, never again I’ll paint my own ta!


I hope you took it back for a refund! I have ceramic coated exhausts using high temp Cerakote on a few of my Lambrettas. One is going on 5 years and on a regularly ridden machine and it still looks brand new. Another has a few thousand klicks and 3 years and also looks immaculate.

Warkton Tornado No.1 wrote:I have amongst my collection of exhausts, an expansion chamber from a 'crosser that is electroless nickel plated. My belief is that coating is extremely durable, considering the harsh environment it is intended for.


The problem is finding someone that will put through their tanks. The company that does my electroless nickel will do almost anything I send them, including forks and U-bends, but won't do gas tanks or exhausts. For gas tanks I have to ship them across the country to someone else to plate.
User avatar
vegansydney
 
Posts: 93
Joined: Wed Aug 07, 2019 2:38 pm
Location: New York City

Re: Changing to clubman exhaust

Postby 68Sxandy » Tue Jul 07, 2020 4:46 pm

I have just changed from a JL3 to a BGM clubman on my mugello 186 kitted sx, runs much better for my old man style of riding. The exhaust seems top quality and the service from TASS was outstanding - 18 hours from order to delivery !!!!
68Sxandy
 
Posts: 176
Joined: Sat May 31, 2014 11:23 am
Location: Warwickshire

Previous

Return to Series 1, 2 & 3

Who is online

Users browsing this forum: Google [Bot] and 17 guests