Temperature difference left to right cylinder

Hey everyone. Getting my 71 commando up to snuff (new tires, fluids, etc) and fired her up today for the first time. Started 3rd kick and idles strong. As it was sitting there idling I checked how the cylinders were warming up. Just after a few mins there was a noticeable difference in temperature left to right side. Left was getting up to the 180 range where the right side was still just over 100. Gave it some revs and let it idle again and checked. Same thing about a 50 degree difference left to right. Checked spark and it was good. Both plugs seem to have fuel on them. Compression test is next but it's running and idles like a rock. Could.it really be compression? Bike hasn't run in a very long time (years) that's why I'm doing the whole refresh. Could it be the carbs? Fuel was drained before storage so it should be ok. Idk..... When the temperature difference didn't change after about 10 mins I shut it off, never took it for a ride. Any advice would be awesome. Thanks again everyone!

If the plugs have fuel on them you are running too rich. Likely the cool side is not firing correctly or the carb balance is way out. Do a full tune up.

I presume are we talking Centigrade here? Where are you checking the temperatures?

Plugs are brand new. Has electronic ignition in it currently. I'm taking the temperature right at the header I front of the cylinder. Tried moving around, checking a few different places but all seems to say the same thing. Left cylinder is way hotter then the right. From my experience with other brand motorcycles the left cylinder seems to be fine it's the right side staying so cool that worries me

Take it for a run before doing anything, put a load on the motor and see how it goes, if its running good without any misfire, as well both carbs can be set/adjusted differently to each side even needle positioning can be set different to each other, have you pulled the carbs apart as be a wise thing to do if left sitting for a long time, as well there is a lot more weight hanging off the left side of the crank, as well not good letting them idle for too long, does more harm than riding them slowly to get up to working temp.

I agree in a perfect world I would pull the carbs off and go through but the previous owned installed different carbs that I still have yet to identify so be able to buy a rebuild kit. They are amal carbs but they are much larger then the factory ones. The owner before said it was a "kit" ( it does have different manifolds) he bought. Said something about later triumph carbs but again I'm not sure. I will eventually pull them off and go through them but I would love to ride this thing for the first time.

Seems you need to find out more about your bike, but if it's starting and running then take it for a ride, get the bike up to working temperature, find out what its doing, can't tune your carbs properly without doing this, as soon as you get back take the plugs out and look to see what they are doing, if the plugs are wet or sooted up then its running too rich, if the plugs are dry and the bike running good without any misfire and starting easy I leave it as it is, but you won't know for sure till you get out on it for a ride and get up to work temp, if its running and starting easy then its pretty close might just need a few fine adjustments, I always carry a small adjusting screw driver when out while tuning my carbs, most tuners will take a bike out first to see what its doing.
As you have said it firing up on the 3rd kick, is idling well, take it out for a good run before doing anything to the carbs, see what its doing first while out, it might just need a good run, clear the cobwebs out, don't be afraid to do this, it has to be ridden to find out what it is doing.

Mgiossi,
Like Ashman says,take the bike out for a run to check things out and myself I stay away from letting it sit there and idle for length of time.
Mike

I appreciate all the input everyone! Back to work for the week so ill be taking her for the first ride next weekend and get back to everyone with the findings. Can't figure out how to post pictures here yet but I would love to show you all the carb setup to see if anyone recognizes them. I bought the bike from the original owner who sadly suffered a stroke so it's difficult getting to many answers from him about the carbs other then they were a kit he bought many years ago lol

Mgiossi said:

I appreciate all the input everyone! Back to work for the week so ill be taking her for the first ride next weekend and get back to everyone with the findings. Can't figure out how to post pictures here yet but I would love to show you all the carb setup to see if anyone recognizes them. I bought the bike from the original owner who sadly suffered a stroke so it's difficult getting to many answers from him about the carbs other then they were a kit he bought many years ago lol

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You probably have Amal Mk2 carbs.