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Why?
Cuts out on hard deceleration
- Thread starter 1973x75
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marshg246
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Besides being a cool look, step one of tuning AMAL carbs is getting the fuel height right. That has two components - the optimal height and being the same between cylinders. Being able to see the fuel height in both carbs while running would be helpful.
AMAL's standard fuel height measurement is easy enough to set and it is based on a level carb. On a Norton, being off slightly between carbs is compounded by the carb angle and especially at idle that can make a big difference since the pilot circuit starts at the back bottom of the carb and only vacuum brings the fuel up through the circuit.
Would it be weird looking, especially if trying to look stock - yes! Is there some good reason to poo-poo something someone would like - nope!
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Being a tight old bastard I drill and tap the float bowl drain plugs and loctite a barb into each, then run a length of clear tube up the side of the carbs through Mk2 air vent clips. Great for setting and checking the levels and draining the carbs. Cost? I would guess £5
On the subject of saving money, and If you make your own gaskets; Gasket material ie Viton etc is going through the roof and getting anything harder than shore 60 seems impossible. A few months ago I had to have the garage roof repaired and here in the UK apparently felt roofing has been banned. The alterative is "rubber". This rubbery stuff looked like it might be good enough for rocker cover gaskets so I rescued a bit, cut off a few pieces and put them into a sealed jar of a mixture of petrol and engine oil. Three weeks later the rubbery bits emerged in perfect condition. I cut out and fitted a set of exhaust gaskets. The nuts torqued up without any notable gasket crush or squish out. Fingers crossed they wont melt or leak.
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When I first encountered VM Mikuni carbs, I did not know the function of the pilot jet. The Mikuni is used on two-strokes which are prone to seizing. Apparently when the throttle is snapped shut, is when the pilot jet works. It is very noticeable, that when a two-stroke seizes, it is often at the end of a long straight, when the throttle is closed for braking. - particularly when using methanol fuel.
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I use a drain plug, hose barb clear tube to set float level in the shop but have never thought about possible use during operation. Interesting idea. makes keeping the float clean when storing very easy, even easier than the drain screws on Keihins.
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I have made and fitted a capped and drilled plug in to the end of each tube, the drilled breather hole is 1mm dia. The theory was to prevent the tubes sliding out of the vent clips and reducing the chance of dirt ingress. In practice the tubes have never moved and are always dirt free.
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