two valve 1200?

Tanabuso Posts : 51 Join date : 2020-09-08 Age : 60

Did guzzi ever make a 2 vale per cylinder 1200 GRiSO?

Don Abbondio Posts : 4725 Join date : 2014-03-13 Age : 66

no, only 1100. A 1200 Sport/Norge/Breva could possibly fit, or you could upgrade the internals to achieve the same, though others might know what and how easy it might be. I just have a 2V 1200 Sport...

GRiSO Capo Posts : 1183 Join date : 2015-08-09 Age : 56

"just" Tony..... scratch

BB is part of the evolution of things, no?

Don Abbondio Posts : 4725 Join date : 2014-03-13 Age : 66

Well Pat, on this here forum, I have a lowly 2V 1200 Sport, like yourself. Others here have "GRiSOs", so only "just" a humble 2v 1200.

Fra Cristoforo Posts : 384 Join date : 2016-04-14

A friend has 1200 barrels on his 1100 GRiSO, everything trimmed to fit.

GRiSO Capo Posts : 7702 Join date : 2013-05-29 Age : 64

What did he do? Deck the tops of the barrels by whatever the stroke difference is? Didn't it significantly change the compression ratio? I suppose it would of lowered it?

Fra Cristoforo Posts : 384 Join date : 2016-04-14

Yes, cut the top. He's at 10.5 compression. 1200 heads w/sunk valves, pistons trimmed on top. It also has a cam I put in at the beginning, some years ago. The 1100 motor had high flowing Mike Rich heads that he'll put back on sometime. Quite the grenade, already touched a piston once. Been apart like 5 times. Some folks just got to tinker.
BUT it really hauls ass.

GRiSO Capo Posts : 7702 Join date : 2013-05-29 Age : 64

10.5 is bloody high for that combustion chamber but the second plug probably helps combat detonation.

Yeah, the old 2V motor is easy to tinker with.

Fra Cristoforo Posts : 384 Join date : 2016-04-14

He's looking for a gearset that will retard cam a bit. He's at the max for crankcase pressure, got an extra hose from dipstick hole.

GRiSO Capo Posts : 7702 Join date : 2013-05-29 Age : 64

Does the Sport have the breather off the side of the timing chest? I can't remember? If it does sticking something like an Ag-bike exhaust spark arrestor in it will help with oil expulsion. It's a common mod with hard used Bellagios. Some sort of windage tray would probably help too.

Tanabuso Posts : 51 Join date : 2020-09-08 Age : 60

sounds interesting chaps

Don Abbondio Posts : 4725 Join date : 2014-03-13 Age : 66

Yes it has that port on the timing chest. Still moves a lot of vapour though, so maybe could do a bit better. I found out how much in actuality one year heading to QLD with Mal. Still trying to clean the oil up...

Was a split collector box, the main spigot that connects to the crankcase vent - folded in on itself on the casting line (two piece plastic welded together). Still stinks when I pull into my garage so I might (then again I might not) do something about it one day, kinda like what Mark did on his embiggenment exercise.