Scooterotica

The Malossi MHR with a 60 mm crank and a 1,5 mm head gasket is around 128/185 that, with a reasonable resonant pipe, should have a nice power band.

If you mean the standard MHR with a 60mm crank has a minimum main transfer duration of 128 degrees, then it wont begin pulling until over 6,000 rpm! If you are going to do this on yours 4th gear will be much better on a PX150 22/67 primary...just saying

Yes 128 mínimum without modification with 60 mm crank.

Are you going to try this in yours? Do you already have the MHR kit or just thinking about it?

I am building one: Malossi MHR, MMW head, MPR reeds, Rz RH Mark 2, 1,5 mm head gasket, banded Cosa cluth, Keihin 35 AS, MTech, 60 mm mushroom crank, etc.

35mm carb? Is that not overkill, I've got a 30mm phbh on my Polini 220, 60mm mushroom/bell crank etc etc and its plenty. GPS at 78mph, well fast enough on 10" wheels thankyou

The Keihin 35 works really well with the Malossi, with the proper needle of course. And no need for pump.

It is going to be a powerful engine but what gearbox will it have? With that long main transfer duration it wont pull well at less than 6000rpm in 4th (even with a T5 cog).

I am not so sure about that. I have being driving an old Malossi with 126/186 (1 mm under and 0,5 up) and it was perfect.
Also I see lots of dyno graphs of engines with 130/190 and they start pulling around 5500 RPM. Although it sounds incredible the latest is 138/198 in Malossi MHR.

Sorry, but my written English is very limited, takes me for ever to write a sentence: I thank Nokia Lumia predicting dictionary