Breva 750 "Upgrades"

[Flay]

You've probably all seen the advice that "you can't do much to a Breva 750". Well, I had mine on a dyno this weekend (thanks to some kind racers) and I can confirm that changing exhausts, while seeming to help the bike rev a little more freely, didn't do much for the horsepower. I think the best run with the Mistral was something like 37.8, with the DB reducers out, it made it to 38.6 hp. Unfortunately, we didn't get to check what it was with the stock cans...

That being said, it sounds terrific. Everybody agreed that it was best with the db reducers out, but that's just too damn loud for me. I'm surprised how well those little inserts work..

 

[ed]

> You've probably all seen the advice that "you can't do much to a Breva 750".

...oh, there's lots that you can do.

http://guzzitech.com/V65dyno3.html


Ed

 

[RJVB]

How much of what you've done with that V65 did Guzzi already do over the years to go from that engine to the Breva's V75? And what mods are more adapted for use on the race-track where one doesn't always care if the engine has to be rebuilt after each competition?

 

[ed]

All of it works on the street. Bike still uses stock cam & stock pistons. I get streetable 15-20% hp & torque gains across the board on smallblocks easily. This bike was raced an entire year with nothing but oil and tire changes.

Ed

 

[Holt]

Re:Breva 750

guzzitech wrote:

All of it works on the street. Bike still uses stock cam & stock pistons. I get streetable 15-20% hp & torque gains across the board on smallblocks easily. This bike was raced an entire year with nothing but oil and tire changes.

Ed

Isn't your V 65 a 4-valve head?

 

[RJVB]

Re:Breva 750

I'm reading this vintage motorcycle mag, and came across a few remarks that had me realise there's a nice challenge around for you

Is a V65 very different from a V50 engine, and if not, how much could you get from one of those? The reason:

The 24 hour speed duration record for the 500cc class still stands at 105mph (plus change) since ... 1963.

 

[ed]

>Isn't your V 65 a 4-valve head?

nope. 2 Valve. 650cc. 52 hp. 41ft lb. Around 15 hp more than the stock Breva below.


Ed

 

[Holt]

Re:Breva 750

guzzitech wrote:

>Isn't your V 65 a 4-valve head?

nope. 2 Valve. 650cc. 52 hp. 41ft lb. Around 15 hp more than the stock Breva below.


Ed

Heron heads, then? Carburettors!

So;

Enlighten us unworthy; what exactly did you do?

 

[NeroGuzzi]

Re:Breva 750

[/quote]

Heron heads, then? Carburettors!

So;

Enlighten us unworthy; what exactly did you do?[/quote]

I think Ed answered that with the link he provided above. Here it is again: http://guzzitech.com/V65dyno3.html

 

[RJVB]

Re:Breva 750

He didn't answer my question/suggestion with the link above

 

[ed]

Mods are all common sense. Gains are mostly from intake mods/headwork, increased compression and other mild performance strategies.

I can get streetable across the board 20% torque/hp gains on any stock Guzzi smallblock.

Ed

 

[Guzzimundi]

Fascinating and definately contrary to common wisdom! But how practical would it be for common mortals to undertake such modifications? Where to get parts? We need a Breva guinnie pig!

Anders, where are you?

 

[Holt]

Re:Breva 750

Guzzimundi wrote:

Fascinating and definately contrary to common wisdom! But how practical would it be for common mortals to undertake such modifications? Where to get parts? We need a Breva guinnie pig!

Anders, where are you?

Right here.

Why? B)

Mods are all common sense. Gains are mostly from intake mods/headwork, increased compression and other mild performance strategies.

Ed's a mean man. B)
But primary is he running a carbed bike. And is the happy owner of a real shop.
Us EFI-powered guys with the garage in the yard really wouldn't be able to do much.


Edit: -unless we're paying someone like Ed to do it......:dry::laugh: