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Inlet Manifolds

Over the years Lambretta scooters have been limited to the carbs they can use by which inlet manifold was available.
Various standard inlet manifolds have been available from 18 to 23mm both in 150 or 200 stud patterns.
125, 150 and 175 engines had different cylinder and inlet stud spacings compared to the 200-engine casing.
Away from standard carbs a manifold was available in the 1960s to suit the Amal solid mounted MK1 carb as mentioned previously.
This manifold could use 26, 28, 30 or 32mm carb bodies.
Over the years these manifolds went by the wayside and as Amal brought out the MK2 version there was very little demand for the manifold.
In the 1970s an Italian company called CDC (Malossi) introduced a solid mounted inlet manifold to suit the PHBH style Dellorto carbs, these were available in both 150 or 200cc type stud holes and to date this manifold has got to be the most common manifold around! The 150 version has dried up but the 200 version is freely available.
This manifolds can be machined down to fit either a rubber mounted Dellorto or an Amal rubber mounted carb.
These manifolds were the only ones available for years and therefore limited which carbs could be used.
Kegra introduced a new rubber mounted manifold in the 1980s to suit the 3000 series 36mm Amal carbs but was only for high tuned 200 race engines and was not really suited to road going engines.
Midland Scooter Center introduced the DJ 4-petal reed valve manifold to suit 200 engines and again was aimed at the larger carb market of 30 36mm Amals.
Both Mikeck and Taffspeed introduced a 6-petal reed valve manifold and was again suited for the larger carb.

MB Developments have over the years specialised in manufacturing parts and products for Lambretta and Vespa scooters.
Large proportions of these products are sand-cast aluminium parts.
MB Developments have seen the need for different carburettors and have specialised in the manufacture of inlet manifolds to suit different types of carbs to suit different applications.
From the mid 1980s we have steadily introduced inlet manifolds to suit the times and requirements from customers.

MB DEVELOPMENTS INLET MANIFOLDS

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Most manifolds are the down draft type which is to be preferred as these seem to perform much better than the side draft type.
The down draft type tend to have an angle of about 25 30 degrees which means the gases enter the cylinder at an improved angle to the original type side draft manifolds.

STANDARD GP 200 22MM

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This is a direct copy of the standard GP 200, 22mm inlet manifold, but is slightly beefed up.
This manifold was introduced because at one time there was a lack of genuine manifolds and these were the times of standard restorations and it seemed every one was restoring a GP 200.

25MM / 150CC DELLORTO PHBL

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This was introduced as already mentioned to upgrade the GP 22mm carb and help improve either standard or mildly tuned engines and still use the original air filter box.
The carb is modern and fully adjustable making it ideal to perfectly set up your engine.
It suited 175 and 190 style engines, which really require a larger carb other than standard.
It could, if required, still work on 125 or 150 cylinders if you opened the inlet port to suit the manifold.
The manifold also suits the 22, 24 and 26mm carb bodies.
You could, if you needed, use the carb as an open bellmouth carb but it wasnt intended for that.

25MM / 200CC DELLORTO PHBL

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This was introduced as all ready mentioned to up grade the GP 22mm carb and help improve either standard or mildly tuned engines and still use the original air filter box.
The carb is modern and fully adjustable making it ideal to perfectly set up your engine.
It suits a stage 2, 3, 4 or even a stage 5 200 motor, which really require a larger carb other than standard.
It could, if required, still work on stage 6 or 240cc cylinders.
The manifold also suits the 22, 24 and 26mm carb bodies.
You could, if you needed, use the carb as an open bellmouth carb but it wasnt intended for that.

26MM / 150CC AMAL MK2

This manifold was used before the Dellorto range was introduced.
Towards the late 1980s MB Developments saw the need for milder tuned engines or engines suited for restored scooters where there was a need for more fuel consumption with less petrol spit back and lower revving engines to keep reliability.
It was ideally suited for the stage 3 and 4 tunes, in fact we introduced the Suzuki 190 and 175 stage 3 tune just for this carb and manifold set up.
This manifold and carb set up was designed as a down draft manifold which worked well and still gave very good power out puts more so than their Dellorto equivalents, but the carb was too big to squeeze in and still use the air filter box.
Amal after a time went bust and made the manifold redundant.
(These carbs have been back in production for a number of years but are more expensive the Dellorto carbs now)
This manifold can also be used for either the 25mm Dellorto PHBL or the 26mm Dellorto PHBH as a down draft carb and manifold set up.

26MM / 200CC AMAL MK2

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This manifold was used before the Dellorto range was introduced.
Towards the late 1980s MB Developments saw the need for milder tuned engines or engines suited for restored scooters where is a need for more fuel consumption with less petrol spit back and lower revving engines to keep reliability.
It was ideally suited for the stage 3 and 4 tunes, in fact we introduced the Honda stage 3 tune just for this carb and manifold set up.
This manifold and carb set up was designed as a down draft manifold which worked well and still gave very good power outputs more so than their Dellorto equivalents, but the carb was too big to squeeze in and still use the air filter box.
Amal after a time went bust and made the manifold redundant.
(These carbs have been back in production for a number of years but are more expensive the Dellorto carbs now)
This manifold can also be used for the 25mm Dellorto PHBL or 26mm Dellorto PHBH as a down draft carb and manifold set up.

30MM / 150CC SOLID CASING AMAL OR DELLORTO

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When the CDC Dellorto 150 inlet manifold dried up there was still a need for them!
So we had a pattern made.
At the same time we beefed up the manifold so we could machine it down to suit either a Dellorto 26, 28 or 30mm rubber or solidly mounted carb or Amal 28, 30, 32 or 34mm carbs or now the Dellorto VHSA 28, 30 or 32mm.
The manifold internal hole is 30mm but has enough room to open out to 34mm if required.

30MM / 200CC SOLID CASING CDC DELLORTO

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The CDC manifold for the 200cc stud patterned engine are still available.
They come already machined to suit the solidly mounted PHBH type carb, but these are now very rare (or is it the fact that we dont recommend them!)
The most common thing to do is machine them down to suit the Dellorto 26, 28 or 30mm rubber mounted carb.
We can also machine them down to the Amal 28, 30, 32 or 34mm carb or now the Dellorto VHSA 28, 30 or 32mm if required.
The manifold internal hole is 30mm but has enough room to open out to 34mm if required.

30MM / 200CC AMAL MK2

This was the first part we ever made!!
In those days castings and patterns were cheaper than now and it was cheaper to make a manifold than buy the CDC item, so we did!
This manifold suited the 30mm Amal and was used on many a tune but as time went on we deleted this manifold for the CDC item.

34MM / 200CC AMAL MK2 (DELLORTO VHSA)

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This carb was so common in the 1980s and we got sick of opening out manifolds, so we decided to have a purpose made manifold to save time and indeed it did!
But as Amal went Bust in the early 1990s and tuning went away from larger carbs this manifold slowly phased out!
But it's come around again as the Dellorto VHSA 32mm has become popular and uses exactly the same rubber!

34MM / 200CC AMAL SMOOTH BORE

In the early 1990s the smooth bore Amal started to become popular mainly because it was new and great things was expected from it!
In reality it was no different from the 34mm MK2 and because of its size and the need for smaller tunes came about the manifold became redundant!
As the introduction of the Dellorto Flat slides it was used again and it also fitted some Mikuni carbs.

34MM / 200CC DELLORTO VHSB

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This carb became very popular to replace the defunct Amal carb.
As the VHSB used a larger carb mount, the CDC item wasnt large enough so a new manifold was made.
This also fitted some Mikuni carbs.

28 38MM / 200CC REED VALVE ASSEMBLY

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For a time in the 1980s reed valve conversions were very popular.
All tuning dealers did them, some were tuned for the road but most ended up over-tuned race engines.
With the introduction of the TS1 cylinder and its benefits the reed valve cast iron engine disappeared overnight!
We offered a six petal reed manifold that had the benefit of two different carb rubbers allowing the use of all types of carbs making it probably the best on the market at that time.
It was impossible to make a reed manifold and carb to still keep the panels on but at that time cutdowns where the norm so this didnt matter.

28 39MM TS1 AMAL AND DELLORTO

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The problems with the standard TS1 inlet manifold has already been covered in the TS1 section.
Basically the standard manifold limited it's use, we manufactured a manifold to clear the frame and locate the carb in a better position.
This allowed the use of the improved Yamaha reed block and then the use of reed packing plates.

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We have one manifold that can be machined to suit either the Amal MK2 28 34mm and the Dellorto VHSA 30 32mm which is the same manifold or it can be machined to suit the Dellorto 34 - 38mm VHSB two groove type.
These manifolds also fit the Mikuni range.

28 38MM / TS1 REED VALVE ASSEMBLY

Following on from the 1980s reed valve boom we developed a 6-petal reed manifold to suit the TS1 cylinder.
When using this manifold on a standard set up cylinder the manifold showed no power increase.
But if the cylinder was bored out to a 250 engine using 71mm plus pistons the manifold came into its own as the standard style reed set up would hit the piston let alone cover up the boost port.
The manifold had carb options from 28mm to 39mm but again we couldnt get the manifold within the panels so it was only suitable for race type engines.

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