Valve clearances

[africatijn]

Hi all,

After fixing the torn inlet rubber (succes! return to idle is good again, maybe even have some of the power back, will put a picture of the torn rubber in that thread tonight), think I'm up for a valve clearance check, and a carb synch check.

As for the valve clearances, according to haynes it doesn't seem to be that difficult, are there any special things I have to consider/look into?

As for the carb synch, the only thing is to get one of those gauges to measure the vacuum in each inlet. Are those very expensive? Where to buy?

Cheers,
Tijn

[robelst]

Valves are not overly difficult to set (just screws), but it is really fiddly to reach the ones at the front cilinder. I usually just lift the rocker cover (difficult to completely remove it without taking loads of bits of) and remove the little inspection cover which gives sort of access (from the top and sides) to all the valves.

I use Boehm vacuumtesters, paid around £30 and they are really good (adjustable damping makes them easy to read). Not sure if Boehm still exists, but this may give you some price indication. In my experience the carb balance hardly changes on an AT, so maybe you could borrow them from someone?

[africatijn]

Hi,
Well, been thinking about buying the synch tool anyway, my brother has a two cylinder as well, so it might be useful every now and again.

Question, are the connections to the cylinder the same for all bikes? Or are those tools supplied with enough adapters to fit them all?

Cheers,
Tijn

[robelst]

Question, are the connections to the cylinder the same for all bikes? Or are those tools supplied with enough adapters to fit them all?

No and yes (well, the Boehm comes with a range of adapters).

[YEN_POWELL]

The Morgan Carbtune gauges come with a range of adaptors and they definitely fit the AT. In fact I've left the adaptors permanently screwed in with my Scottoiler plumbed into one carb and my Vacuum fuel pump plugged into the other.

I can check the carb balance in about 2 minutes including trying to remember where I've left the gauges(the tank stays put). Naturally because they are so easy to check and adjust, they never go out of sync. Sneaky Japs.......

[ogri wannabe]

Did you say easy to adjust!! I keep mistaking the idle jet screw for the carb balance screw and you need to be a contortionist to reach it. I always end up having to take the tank off so that I can see what I'm doing!

[YEN_POWELL]

On my bike the upside down adjusting screw is painted yellow. A simple body harness allows me to hang upside down from the garage rafters next to my bike.

This means that to me I am looking down at the screw, not upward with a twisted neck. The downside of this, is that carb balancing must be completed before the blood rushing to my head makes me pass out. I think the neighbours are still talking about the last time they found me this way. Now of course I never attempt this type of work without a Royal Airforce aircrew harness cutting knife strapped to my left leg, over my workshop chamois lederhosen!!

[paultheold]

Personally I take the Engine out to set the valves, at the present rate that is once every 24K, as for balancing the carbs I find it hard to run the engine on a bench. I only found the balancing screw when the carbs were of the engine.
Try parking on the edge of a cliff, climb partly down the cliff when your head is level with oil filter you can look up and adjust the screw.
well it is 6.15am, and I am at work]

[TJE]

On my bike the upside down adjusting screw is painted yellow. A simple body harness allows me to hang upside down from the garage rafters next to my bike.

This means that to me I am looking down at the screw, not upward with a twisted neck. The downside of this, is that carb balancing must be completed before the blood rushing to my head makes me pass out. I think the neighbours are still talking about the last time they found me this way. Now of course I never attempt this type of work without a Royal Airforce aircrew harness cutting knife strapped to my left leg, over my workshop chamois lederhosen!!

Haha ... I have to admit you're a genius, Yen ... even though you're scaring me a little

[YEN_POWELL]

Haha ... I have to admit you're a genius, Yen ... even though you're scaring me a little

That made me laugh too. I have absolutely no memory of ever writing that.