Bandit 2250 exhaust glowing

[john87]

On 08/12/2023 at 19:19, spudulike said:

An interesting comment. You could possibly put a mark on the ignition flywheel and strobe it to see if you get any form of advance and retard when the engine is revved....assuming the engine has some sort of advance/retard device or mechanism.

Did a LOT with engines years ago, cars and lorries. On something with quite a short exhaust, like lorries used to have, sticking out the side, you would find things that were well flat. You could put your hand in the exhaust gas as it came out he exhaust and it would be very hot. You would then check the timing, find it retarded, set it correctly, as lo and behold, it ran much better AND when you felt the exhaust fumes they were a LOT cooler.. That was how i learnt this.

 

People think that the fule air mix is burning all the way down the power stroke. It is not, it burns at the very top and the rest of the power stroke is just expansion of the hot gasses. If the timing is retarded though the gas will still be burning as it is pushed out of the exhaust..

 

Anyone that doubts this need only look at a two stroke. If the charge was still burning by the time the piston uncovered the exhaust and transfer ports, the incoming charge would be ignited too. The thing [unsurprisingly] would not run properly if at all and would spit back out of the carb in a big way while trying to stagger around..

 

john..

[hamdogg]

On 16/12/2023 at 14:53, john87 said:

Did a LOT with engines years ago, cars and lorries. On something with quite a short exhaust, like lorries used to have, sticking out the side, you would find things that were well flat. You could put your hand in the exhaust gas as it came out he exhaust and it would be very hot. You would then check the timing, find it retarded, set it correctly, as lo and behold, it ran much better AND when you felt the exhaust fumes they were a LOT cooler.. That was how i learnt this.

 

People think that the fule air mix is burning all the way down the power stroke. It is not, it burns at the very top and the rest of the power stroke is just expansion of the hot gasses. If the timing is retarded though the gas will still be burning as it is pushed out of the exhaust..

 

Anyone that doubts this need only look at a two stroke. If the charge was still burning by the time the piston uncovered the exhaust and transfer ports, the incoming charge would be ignited too. The thing [unsurprisingly] would not run properly if at all and would spit back out of the carb in a big way while trying to stagger around..

 

john..

That is as like working out algebra to me 🤣