GT200 base gasket vs stock transfer port comparison (seeking pics)

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Davidsquaredson
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Hi, I slapped on a GT200 years ago, runs great, but I didn’t open up the transfer ports. I’m wondering if someone who has both GT and stock base gaskets on hand could post a pic of one overlapping the other so I can see the difference. I’m trying to decide if there is enough difference that it would be noticeable. My scooter is running like a Swiss watch right now so I’m not going to mess with it for a minor improvement.

Thx in advance
David
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tony172
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After the recent record and advancements by darrell Taylor, I wouldn't bother. Nice though it is to see smooth matched transfers, 58bhp and 127mph on an untouched, unwelded Italian case speaks volumes to me. That and the back to back testing of engines in a wide range of tunes before and after matching and flowing making no difference on the dyno
Mrnice71
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My thoughts as well minimal gains if any , leaving the casing standard also gives the option to change the cylinder in the future , matching also weakens it and gives less gasket face which can cause problems .
Davidsquaredson
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Thanks very much. Exactly the sound advice I was seeking.


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carpe scooter diem

1974 Rally 200
1965 Li150
1963 TV175
1974 Eibar Jet200
Warkton Tornado No.1
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tony172 wrote: Thu Dec 03, 2020 10:28 pm After the recent record and advancements by darrell Taylor, I wouldn't bother. Nice though it is to see smooth matched transfers, 58bhp and 127mph on an untouched, unwelded Italian case speaks volumes to me. That and the back to back testing of engines in a wide range of tunes before and after matching and flowing making no difference on the dyno
Every 'component' within the two stroke engine has an effect that overlaps the function of others to create the result.

Get the recipe absolutely right & it should be what somebody loves.....but not always to everybody's taste.

As yet, there is no definitive Lambretta based engine, though the science involved has made many of us have more open minds in recent times.

Just as some of us still cling to the theoretical benefits of HPC, others have proven that substantial lowering of primary compression yields benefits. That, too, has been proven in the motorcycle world simply by fitting a longer rod to an otherwise unaltered engine gains power/torque. Rumour has it that Charlie Edmonds went to the nth degree to gain crankcase volume & as yet, his Group Four piston port motors remain the most powerful I am aware of.

So I wouldn't completely dismiss the thought of matching & enlarging transfer ports unless you can buy into the precise, quantifiable deal of the DT format.

As for TV200 base gaskets, I'm unaware there was a difference. Head gaskets & combustion chamber design changed a number of times during production of the TV/SX200. Ports of the TV changed during the production run, too.

Crankshafts also changed with regard to balance.
YAMLAM
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As for TV200 base gaskets, I'm unaware there was a difference. Head gaskets & combustion chamber design changed a number of times during production of the TV/SX200. Ports of the TV changed during the production run, too.

Crankshafts also changed with regard to balance.
[/quote]

I have a feeling he means Gran Tourismo200 as oppossed to TV200.
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Rich_T
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There is about a 2mm step on the inlet side of the transfer port. You wouldn't notice the performance difference in practice and if it were an Italian case I would highly recommend that you do not match the casing as it will be de-valued.
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