Fuel restriction.

[Johnny4428]

This cracks me up! Could never understand why the outlet on some of these taps weren’t positioned away from obstructions like out the back of the tap horizontally. Had a nice run out a few days ago on returning the engine started making a horrible noise and instead of stopping I limped along to get nearer home until eventually it cut out completely. I did think it was catastrophic. After having a good look around couldn’t see any oil or fluid leaks anywhere. Pushed the button to start and away it went so hopped on and drove home. This is what I discovered when I got back to base.
Sorry if pic 90 out. Click and it’s fine!

[Bryn]

Having just changed the plugs, added an in-line fuel filter and put the tank back on 10 minutes ago I notice my tap outlet goes out the back of the tap horizontally (550K3)

[K2-K6]

Some of the earlier taps look like they weren't bespoke, more off the shelf type arrangement tgat didn't take account of other items close by, not a huge amount of room around there anyway.

Original fuel pipes had quite thick wall, making them resistant to kicking like this too.

Wouldn't hurt to use length change in looping lower and back up again to ease pathway either.

K type 750 would usually run for about 3 miles with fuel off just on float bowls as I often turned mine off on way home to habitually leave the carbs more or less empty when not in use.

[Pauarc]

I think the fuel pipe should go through the carb housing

[Laverda Dave]

I think the fuel pipe should go through the carb housing

That's a great idea, I wish the 400 had that arrangement as the fuel pipe sits on top of the carbs. I know it is double skinned and has the spring heat shield arrangement but it looks ugly.

[McCabe-Thiele (Ted)]

Some of the fuel hoses seem very soft walled and go even softer in use.
I have used this on my 500 as it was fitted by Gerben or PO it's reinforced as well so does not flatten easily.

.https://www.ebay.co.uk/itm/334357613189

[Pauarc]

On the k2 it has 2 holes for the fuel pipe as 2 goes through housing

[Johnny4428]

Thanks guys for input. My 550k3 has the same problem outlet coming down towards inlet rubber. I’ll check carb bank for possible alternative routing and seek some stronger walled fuel hose.

[Johnny4428]

Trimmed back the kinked hose and tried this for fun.

[McCabe-Thiele (Ted)]

Your new routing looks much better - presumably that is a 400 type spring/heat shield.

I like a clip on the petrol pipe for peace of mind on my 500 - very tricky putting a spring clip on my 500 as there isn't much space at the carb ends. Mine has the twin pipes.

[Johnny4428]

Just an ordinary spring out of a bag of mixed ones I bought years ago (if you haven’t got one in your w/shop get one now). Unfortunately wasn’t my problem which turned out to be rust in the tank. After taking her out for another run, I soon realised I was in trouble. After limping home and removing fuel connection and attaching hose into container there was just a very slow trickle, it’s a wonder it ran at all. I have now cleaned out the tank and it’s fine, although I haven’t had a long run out yet.
Prior to winter layup last year I drained fuel and gave the inside a diesel wash on the 550. On the 750 I just filled right up with fuel. Looks like the fuel filled tank didn’t fare as well as the empty tank. It was good to carry out a comparison though. I will be going down the drain and diesel wash route from now on as recommended by NJ.