WHICH...new engine case

[Strummer10]

Guys.....just considering the merits of

1/ Building a new 225 engine in a sourced second hand 200 engine case

versus

2/ Buy one of these new engine cases on the market.....understand there's a few now on the market ?

Does anyone know what's currently out there now released prices, web links etc and what's about to land in the new year ?

Many Thanks in advance....

[jonashford]

Misano is avalaible now,

I think the gt is almost completely available altho Im not certain as its getting parts added to it as progress goes on.

Casa im not sure

[Strummer10]

Thanks Jon, sounds like 2017 is the year they all go live then...

[Knowledge]

As you say Strummer, it will be an interesting year.

As far as I can see, the driving force behind the redesign of each of the new casings are to address issues around the crank. The main issue with the current crank is that the webs are not very wide, so the press-in big end pin does not get as much of an interference fit on the webs as it would if each web was, say, 5mm thicker. Hence a tendency to twist. There are also limits on the stroke of the crank as the standard webs are only 99mm(?) in diameter. If the webs were increased to, say, 110mm diameter webs, the stroke could be increased beyond current limits (or increased to current limit with a greater margin of safety).

The other issue with the existing casing is the gasket face for the barrel and associated stud-pattern. One limits the gasket area available for enlarging the transfers, and the other limits the location of transfer ports, boost ports and exhaust sub-ports in the barrel. As a result, the new casings have more gasket face and can have undefined stud positions, allowing the use of bolt-down barrels without studs.

The question you need to be addressing is whether this is necessary. If you are building a touring TS1 engine (18-21bhp), then a new casing seems over the top, as plenty of people are using traditional casings in such configuration with great success. Having said that, there are reports that many of the customers who have purchased the new casings are fitting rather traditional barrels, such as Rapido or TS1, rather than waiting for the higher spec barrels to be developed.

I think what is exciting about the new casings is what will happen in the next 5 years, as people think about the new opportunities that the casing opens up. I would like to think that this will lead to a nice 250cc machine that is super-reliable 30+bhp which is both fast on the open road and very rideable in town.

There are rumours that just such an engine is being developed around such a casing, but if your aspirations are for something a little less powerful and a little more affordable, then why buy a new casing?

As you say, these are interesting times.

[Strummer10]

Hi Knowledge / others,


thanks for responses
decision made ......gonna build the TS1 into an existing casing (maybe even a 150 converted one as that's in better condition). No point over specifying my requirements as you mention and whilst I enjoy another years scootering the 'developing world' beyond will unfold and I can see whether I go that route down the line or settle for a 400cc Scomadi which was my intention (only to replace my Vespa GTS commuting scoot).

Regards