More torque from Malossi 210?

Hi,

I have troubles choosing between the Pinasco and the Malossi kits. I want a reliable touring machine with good torque and decent top speed. I friend of mine came up with the idea of removing ca. 1 mm at the cylinder base of the Malossi to get the port timings shorter and make it stronger on lower revvs. Has anyone tried this ? Would it work even in theory?
I would for some reason prefer the Malossi for the big transfer ports and the good availability of pistons & rings.

I wrote this excel spreadsheet a while ago, it lets you see what effect changing stroke, port heights etc. will have on your engines geometry, hope it might be useful.

[:drink:]

Hi Nimime I’m just about to try lowering the port timings on a malossi 210. It works well on Lambretta TS1 kits which I’ve done with success. Never tried it on malossi but it should work. You must remember to machine the spigot by a mm as well. SIP sell 1mm headgaskets which you will need. Extra torque can also be gained from machining the piston so there is greater transfer area and widening the exhaust port. Use either the B-Race, JL RZ left hand or right hand for most torque. As Aplus says the 60mm ansd pinasco will give bags of torque but I personally think the mazzecheli cranks are a bit hit and miss. I am running the polini with the GS piston with no problems at the moment. This also gives what you are looking for.

Hi again,
and thanks for your replies! Diablo and ozzy, have you calculated the timings if you lower the Malossi by, say, 1 mm ? I know it can be done with an Excel application, I just don´t know how to run it… It´s true that the different effect on transfers and exhaust might be a problem . Of course, if it turns out not to work it´s fairly easy to add a 1 mm gasket at the base.
Also what I forgot to say is that I´m running a stroker crank, which probably will exaggurate the timing differences, right? I´m going to have it welded and machined to close at about 65-70 degrees with the casing opened to take a 28 carb (no reed!). I´m running a standard carb at the moment.

I’m very intrested in this thread,please keep us informed of your findings.

As a few users on here agree it’s just a pity that Malossi didn’t copy the Polini porting from the start.

Thanks Stringy, perfect! And easy to use even for a beginner like me.[;)]

I don’t know, but if you want a very reliable engine for touring go for the Pinasco and a Mazzucchelli long stroke crank. A modified Pk flywheel and a good exhaust will maximize the perfomances. You can also mantain the original exhaust but I would’nt counsel it. Keep the original gearing and work the transfers on the case… I used a personally lighthned Pinasco flywheel but some of them are not well realized. 24-26 mm original carb if you have the mix or a 28 mm if you don’t need it.
I had all this and my Vespa reached 120km/h at full charge with a passenger. For what concern the piston I wouldn’t worry. I rode 40.000 kms without troubles and after I sold the engine it rode for other 20.000 Kms. The Malossi is a good kit but sometimes give rattling problems because of the wrong size of the piston.
This is my experience perhaps that other scooterists might add something more than me.

not so sure about this lowering idea… 1mm on the exhaust port is worth a few degrees, but 1mm on the transfers is worth about twice that… lower transfers equals less chance for your pipe to be effective therefore less power with a narrower power band… i’d probably look at a tourqey’er pipe with a not to large carb, PM pipes are supposed to be good for good general torque… saying that i’ve ridden a malsossi rather nice 210 built by our very own BEERACE, making 24.5hp that still had very good usable power band using one of his pipes… very smooth and quick… i’d either get the right pipe or buy a kit designed with modest timings,

ozzy