Hi, some suggestions, as mentioned by the other commentors the manifold leak is one. There could be a biasing in the direction the carb faces biasing the right cylinder...this was often the problem with the BSA super rocket which needed a biased gasket, ie wedged shaped to twist towards the leaner cylinder. Could be the ignition is retarded on the left points and making it run hot. Also the points if it's a point bike should be adjusted with equal gaps for both cylinders and the should be advanced relative to one another by opening the separating plate not adjusting the gap. I've loved many years with a 72 bonneville which is a daily rider 😊
Yes, I agree. (The bike does has an electronic ignition.) That biasing info is interesting. Never heard of that. The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
@@fjdelmonte hi you get a digital thermometer and measure the surface temp of the bends to see if the problem persists. May have been a tight tappet causing the valve to not seat properly.
[13:22] well you’re the guy in the shop but from where I sit it sounds like 2 & 4 millimetres, even your fingers look like they are travelling. When I test by feel on my two 70s trumpets the exhaust .002 is barely discernible as a click and the inlet only just more so. That sounds like the 10 & 8 of a late T140. Obviously I speak from my sofa 😊😊😊
I have owned a 1972 TR6RV since 1975. Where I live is a little over 1000 feet above sea level. With stock 9:1 pistons, I have always gotten 140 to 150 lbs compression on both cylinders. I think 130 is good, but not outstanding.
Have you checked the plugs are same temp rating, NC3 etc. Also is there oil coming out of left or right exhaust? If there is a valve guide leak (for example) it will affect burn temperature.
My left hand cylinder used to run hotter on my 72 t120 bonneville until I discovered a triumph service bulletin that said the rocker shaft washers were installed incorrectly at the factory and insufficient lubrication could affect the pushrod ball ends and rockers on the left side. I followed the recommendation and now it seems to be better.
As some others have mentioned. Check manifold gaskets for leaking, also check exhaust pipe on that side is tight at the head. I don't know if this bike has points or not, but if it has points, good chance timing for the left cylinder is out.
Yes, I agree. (The bike does has an electronic ignition.) The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
If it came in with one pipe blued and one not blued it could be that whatever caused that has already been cured. Use an infrared thermometer to check the temperature of both pipes to see if and how much one is hotter than the other.
Agree. Next time on the lift a temp reading will be step one, then spray carb cleaner on intake manifold. Then possibly act out the old saying, "When in trouble, fear or doubt, run in circles, scream and shout." Sounding better and better each day.
My first thought was ignition timing imbalance, if it still has points. Inlet manifold leak is another possibility, easily checked with a squirt of brake cleaner while it's idling. Those downpipes (headers) are notoriously bad for leaks, as they are just a push fit into the ports, with only the steady brackets holding them in place (I see that one doesn't have the balance pipe, which normally helps to stabilise the attachment). On my T140V, I had the ports threaded to take the screw-in collars and the clamp-over type downpipes, a much better, gas-tight setup.
Yes, I agree. The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I'm asked the owner if he knows the history.
Yes, I agree. (The bike does has an electronic ignition.) The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
Welcome to the channel. Welcome to the channel. Actually these vids aren't intended to be tutorials or educational. They started out as progress reports for the bike owners and I didn't think to make them Private when I published them. Now folks found them and seem to like them so I keep doing them. They are crude (unedited) but every now and then a small bit of good info creeps in. Ride Safe! Ride On! F.
Check for possible air leaks at inlet manifold gasket/s.
Hi, some suggestions, as mentioned by the other commentors the manifold leak is one. There could be a biasing in the direction the carb faces biasing the right cylinder...this was often the problem with the BSA super rocket which needed a biased gasket, ie wedged shaped to twist towards the leaner cylinder. Could be the ignition is retarded on the left points and making it run hot. Also the points if it's a point bike should be adjusted with equal gaps for both cylinders and the should be advanced relative to one another by opening the separating plate not adjusting the gap. I've loved many years with a 72 bonneville which is a daily rider 😊
Yes, I agree. (The bike does has an electronic ignition.) That biasing info is interesting. Never heard of that. The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
@@fjdelmonte hi you get a digital thermometer and measure the surface temp of the bends to see if the problem persists. May have been a tight tappet causing the valve to not seat properly.
[13:22] well you’re the guy in the shop but from where I sit it sounds like 2 & 4 millimetres, even your fingers look like they are travelling. When I test by feel on my two 70s trumpets the exhaust .002 is barely discernible as a click and the inlet only just more so. That sounds like the 10 & 8 of a late T140.
Obviously I speak from my sofa 😊😊😊
I have owned a 1972 TR6RV since 1975. Where I live is a little over 1000 feet above sea level. With stock 9:1 pistons, I have always gotten 140 to 150 lbs compression on both cylinders. I think 130 is good, but not outstanding.
One of the reasons I like single carburetor.
Possibly the fact the exhaust balance pipe has been removed? Exhaust valve seats?
God bless you Frank. 🌞
Have you checked the plugs are same temp rating, NC3 etc.
Also is there oil coming out of left or right exhaust? If there is a valve guide leak (for example) it will affect burn temperature.
My left hand cylinder used to run hotter on my 72 t120 bonneville until I discovered a triumph service bulletin that said the rocker shaft washers were installed incorrectly at the factory and insufficient lubrication could affect the pushrod ball ends and rockers on the left side. I followed the recommendation and now it seems to be better.
www.tioc.org/britbike/Coatesbulletin25.jpg
OK! That's a new one on me! Wow! I will take a look and see if I can see the rocker washers. Thanks.
As some others have mentioned. Check manifold gaskets for leaking, also check exhaust pipe on that side is tight at the head. I don't know if this bike has points or not, but if it has points, good chance timing for the left cylinder is out.
Yes, I agree. (The bike does has an electronic ignition.) The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
If it came in with one pipe blued and one not blued it could be that whatever caused that has already been cured.
Use an infrared thermometer to check the temperature of both pipes to see if and how much one is hotter than the other.
Agree. Next time on the lift a temp reading will be step one, then spray carb cleaner on intake manifold. Then possibly act out the old saying, "When in trouble, fear or doubt, run in circles, scream and shout." Sounding better and better each day.
My first thought was ignition timing imbalance, if it still has points. Inlet manifold leak is another possibility, easily checked with a squirt of brake cleaner while it's idling. Those downpipes (headers) are notoriously bad for leaks, as they are just a push fit into the ports, with only the steady brackets holding them in place (I see that one doesn't have the balance pipe, which normally helps to stabilise the attachment). On my T140V, I had the ports threaded to take the screw-in collars and the clamp-over type downpipes, a much better, gas-tight setup.
Yes, I agree. The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I'm asked the owner if he knows the history.
Ticking over. Carb cleaner around the inlet manifold.
Yes, I agree. (The bike does has an electronic ignition.) The first things I'm going to do this morning is check the tightness of the exhaust and then spray some carb cleaner on the intake manifold. BTW: The bike came into the shop with the left pipe blued, so the problem may have happened a long time ago and was corrected and the pipe not replaced. I asked the owner if he knows the history.
If header is loose in the head you’ll see a puff of exhaust smoke at the vanity ring.
You like repeating yourself don't you ! just get on with it .
Welcome to the channel.
Welcome to the channel.
Actually these vids aren't intended to be tutorials or educational. They started out as progress reports for the bike owners and I didn't think to make them Private when I published them. Now folks found them and seem to like them so I keep doing them. They are crude (unedited) but every now and then a small bit of good info creeps in. Ride Safe! Ride On! F.