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Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:30 am
by sean brady scooters
so are you saying that all that counts is the size of the trans in the bore ?

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:32 am
by sean brady scooters
so time /area

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:32 am
by Darrell Taylor
Muppet wrote:transfer ports would normally taper down the length of the tract so I would have thought to feed the transfers the cross sectional area of the feeds in the case should be slightly greater or at least equal to the combined initial cross section of the feeds
:?
muppet,
so a venturi exists,is that beneficial?

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:36 am
by sean brady scooters
lol there you go again darrell answering a question with a question ...

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:38 am
by Darrell Taylor
sean brady scooters wrote:lol ,just look at any 125 cc motor ,...gagiva /apprilia etc ...they are twice the size of the biggest lamby ports
ive been tuning/developing aprilia rs125 (rotax 122 motors) for around 10 years for superteen racing and as you say are twice as big ,but like mx motors have the fully developed transfer ports with good directional control

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:39 am
by sean brady scooters
ok so ...?

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:40 am
by Darrell Taylor
sean brady scooters wrote:so are you saying that all that counts is the size of the trans in the bore ?
the clue is in the name
TRANSFER

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:42 am
by Muppet
Darrell Taylor wrote:
Muppet wrote:transfer ports would normally taper down the length of the tract so I would have thought to feed the transfers the cross sectional area of the feeds in the case should be slightly greater or at least equal to the combined initial cross section of the feeds
:?
muppet,
so a venturi exists,is that beneficial?
Now mr Darrel that's very unfair; I know I finished my post with a question mark but it's gone in your reply/quote, did you work for the News of the World? :lol:
I would guess that YES a slight Venturi effect would be beneficial to help give momentum to the gas stream; but it's a guess as I don't design two stroke engines for a living; just read a few books and looked at many two stroke barrels,

muppet

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:44 am
by Darrell Taylor
sean brady scooters wrote:ok so ...?

The lamby cylinders dont have fully developed ports with good directional control so the emerging transfer streams lose control

Re: TS1 Sprint/race engine, pics of porting in progress.....

Posted: Mon Jan 02, 2012 1:49 am
by sean brady scooters
lol