Delorto/jetex Main jet larger than 135

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kejj
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I'm looking for a main jet larger than 135.
Scoots restorations largest is 135 and need to go furtherup!

Reason is a new medium tank and a remote air filter. I'm too lean now that the sh2/22 carb is flowed with air!

Suggestions?
Last edited by kejj on Tue May 22, 2012 10:18 pm, edited 1 time in total.
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DaveTomo
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I am playing all the right notes, but not necessarily in the right order.
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Bofs
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Or make your own to suit. They`re brass,easily drilled and this kit can take you up to a 160 main.
Muffspeed....no muff too tuff
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1957 Zundapp Betta 500 Auto
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pasner
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kejj wrote:I'm looking for a main jet larger than 135.
Scoots restorations largest is 135 and need to go furtherup!

Reason is a new medium tank and a remote air filter. I'm too lean now that the sh2/22 carb is flowed with air!

Suggestions?
Dont go too far, Im using a 142 main jet with my jetex, open mouth. Standard Indian 200 stage four, JL3. Plug colour dark brown.
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kejj
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Thank you all for the advices.
I'm at 135 now. Jetex with a kn style air filter connected on a rubber mount to clear it away from panels.
Standard Indian gp200 stage4 factory. Jetex sh2/22, scootrs ss exhaust.

Idea was to go up on main until it 4 strokes and then pull back.
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Lambretta LiS150 1965 - MBGM RT195 w/MBGM Clubman & Keihin PWK28
Lambretta TV175 1962 - GranTurismo 200 w/MBGM Clubman & Dellorto PHBH 28
http://tv175.wordpress.com/
nelson pk
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If it is a jetex and not dellorto........the main issue i believe when adding any modification to enhance performance (exhaust etc) is the atomiser is not big enough for this to let enough fuel through and it should be drilled (cant remember what drill bit to use but it used to be on the LCGB website and i was also told to do this when i fitted a JL3 by a well known shop, when i was using a jetex.
For example my mate had a jet200 engine running a clubman and a jetex and the power was being strangled even though he had upjetted. We drilled the atomiser out to the suggested amount and it was instantly better.
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kejj
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nelson pk wrote:If it is a jetex and not dellorto........the main issue i believe when adding any modification to enhance performance (exhaust etc) is the atomiser is not big enough for this to let enough fuel through and it should be drilled (cant remember what drill bit to use but it used to be on the LCGB website and i was also told to do this when i fitted a JL3 by a well known shop, when i was using a jetex.
For example my mate had a jet200 engine running a clubman and a jetex and the power was being strangled even though he had upjetted. We drilled the atomiser out to the suggested amount and it was instantly better.
good tip, now who has that amount.
I´ve changed the atomizer to the delorto one.
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Lambretta LiS150 1965 - MBGM RT195 w/MBGM Clubman & Keihin PWK28
Lambretta TV175 1962 - GranTurismo 200 w/MBGM Clubman & Dellorto PHBH 28
http://tv175.wordpress.com/
nelson pk
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Just copied and pasted from the LCGB site for you:

There are four sizes of atomisers, 5889-1, 5889-2, 5889-3 and 5889-4. Majke sure you fit the correct one to your set up, as most of your riding is probably done on the atomiser, as this works from roughly 1/4 to 3/4 throttle. One tip on tuned machines, it is sometime prefferable to drill the bottom of the atomniser (more so on Jetex atomisers) if you need a richer mid range. Start by drilling to 2.00mm, if you still need more fuel, 2.5mm.

The jetex atomisers seem to be the worst culprits but it doesn't rule out delly ones in the above text. If your finding you have to use a massive main this could well be the issue. Worth a try for £5 worth of atomiser.
pasner
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Thanks Nelson, useful tip ;)
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kejj
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And for general Knowledge, it seems that only one automiser is now available from dellorto, all other are discontinued.
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Lambretta LiS150 1965 - MBGM RT195 w/MBGM Clubman & Keihin PWK28
Lambretta TV175 1962 - GranTurismo 200 w/MBGM Clubman & Dellorto PHBH 28
http://tv175.wordpress.com/
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