Hi there I have just purchased a set of 4 vacume gauges so that I can tune my 1992 1000 and thougth I would ask if you have any tips on the rights and wrongs as I havent worked with vacume gauges for a lot of years.

 

The actual reading on the gauges is not important. Adjust the carbs so they show the same or near to same value. This should be done on idle, just above 1000 rpm. If the needle jumps a lot, you can put a restrictor in the hose about 10 cm from the carb end. The restrictor shall have a very small hole for the air passage, about 1 mm or so only.

You should only adjust the mechanical settings which control the throttle blade opening. I beleive there are three adjusting screws which can be reached from above, one for each outer pair and one to balance the two pairs.

The pilot screws are adjusted another way, by checking when the idle rpm drops 50 rpm and then open the screw 1/2 turn. You better check this in the manual, I'm not sure i remember right regarding pilot screws and have not adjusted them om my bike. I just opened them 2 1/2 turn and the engine runs like a missile.

 

Carb Sync with pictures
This is for a '96, but it should be the same.

 

Thank you for a very helpful insight on how to sync my carbs, one question for if you dont mind ? At present my bike is running very well, do I leave well enough alone or do you think I should tinker with the carbs as it has no dead spots at all the only reason I asked about sync the carbs was that it doesnt exactly idle 100 percent smoothly doesnt have a miss or anything just doesnt pur evenly, I also dont know the history of the motor but the biek seems to have been looked after before my purchase

 

Well... there are a number of things to check out. Compression test, valve adjust, new spark plugs, carb cleaning (especially if it's sat with gas in the carbs for any length of time) and finally a carb sync. All of these are easily done if you are handy and have a bit of patience. The valve adjust isn't that hard on these bikes. Just make sure to follow the proceedure in the manual, and you'll be fine.
Having said that, mine has never been rock steady at idle. However, with the carb sync it doesn't shake the mirrors anymore.

 

Thanks for the advise Captain I will let you know how I go

 

Just a note with the carb synch.

The previous owner of my bike was very helpfull and attached vacuum hoses to all the points on the engine and left them on the bike with plugs in.

So next time a carb synch is due no more messing about. Just plug into the vacuum lines which are all now poking out the top of the carbs.

 

If you are using mercury gages do not rev the motor or you will suck mercury into the motor.

If you are using vacuum gages, they will bounce all over the place if you use them by themselves. You will need a restrictor as R1000 said. I have never tried it but was thinking about a small valve like a fish tank uses to control the air to at different places in the tank, one in each line. Some kind of buffer may help also, something of volume in each line to suck up the changes in vacuum and even it out.

I found that if a bike surges at lower speed, the crabs may need syncing.

Also, my '94 has an auto fuel shutoff. A vacuum tube off #1 port opens the fuel flow to the motor. This is where I attach my gage. I have to put a tee in line to keep fuel flowing to the carbs when synking.

 

Yep... I've said it before and I'll say it again....
Morgan Carb Tune sticks. The best thing since two ply toilet paper......

 

Thanks for pointing that out I have done the same