Removal of accelerator pumps - Le Mans 1000

Some years ago, in order to get a lighter throttle, I changed the contraptions on top of my 40mm carbs for ‘Spada’ tops. This, with a cable lightening kit from someone, I can’t remember who, I had a much reduced opening pulling pressure.
But… what if I remove the actuating arms for the accelerator pumps altogether??? Has anyone done this and if so how was/is it?
I’m interested to know before I try myself.
Thanks Roger

PS. What do the original carb. tops do anyway that the ‘Spada’ tops don’t, apart from look the biz?

I seem to recall that they give a quicker throttle action - but at the cost of so many extra springs :slight_smile:

I would not remove the accelerator pumps, they are efficient carburettors and there is no surplus fuel to help you accelerate - so it will be heistant and slow to respond.

The pumps were fitted by the designer for a reason, (the old square type carbs also had a similar enrichment device):+1:

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I use the bell crank tops with the external springs removed, you can fit the same lighter springs used on the flat top carbs under the bell crank too, I can’t see any benefit in disconnecting the accelerator pumps as it takes very little effort to operate them, just take the slide out and press the plunger button to see !
I use a twin pull Tomaselli throttle with Venhill cables, it’s as light as I can get it, I’ve never had any problems with the slides hanging up when riding it hard on the road but it my be a different thing if used on the track


Thanks all and thanks Keef_Mayhem, I think I’ll try your set up as I’m sure using bell cranks ( I played with mine this afternoon having been carefully put aside 30 years ago) turns the cable pull from the horizontal to the vertical with a lot less friction than my flat top cable elbows.
And a quicker throttle response would be welcome. Thanks 350lcjohnny
What were Moto Guzzi thinking when they made a throttle so heavy that it wasn’t usable?