Metallic chain rattle after down shifting at low speed

Could be the timing chain tensioner being stuck or something loose. How does it accelerate?

when oil is cold it is thicker and stays [on]coats metal as oil warms up it thins out and flows better[makes it thinner will hear ticking] sounds like a bad lifter or even camshaft lobe problem ,could also have a problem with a loose or out of adjustment rocker arm

When is the last time you checked the tension on your primary drive chain? Remove the round plug at the top of the primary cover. You can reach the primary chain through this hole. Use your finger to gauge the up and down movement of the chain. If you need to adjust the chain, on the bottom of the primary is an adjusting bolt with a lock nut. Loosen the lock nut and turn the adjuster upwards to tighten the chain, lower it to loosen the chain. The chain should have 3/8" to 1/2" of movement with the engine cold. Usually the final drive belt won't make a rattling noise since it's a rubber-like compound. It should have a tension of about 1/2" up and down movement with a force of ten pounds applied to it from the underside of the lower run.

Good Luck
Steve

The limits on the derailer need to be adjusted. You will see 2 adjustment screws on it; one to tlimit the inside travel and the other to limit the outside travel. You will need to turn in the one for the inside travel. You can test it by having the bike upside down an putting it in low gear. Adjust it so that when you shift into low, the chain is centered on the low sprocket.

noises are tough, but try getting under the car when the engine is cold and it has been sitting for a while and hit (with your fist) the catalytic converter-the substrate in cats break up and cause rattles that are especially noticable when the vehicle is running at low speeds.

Measure the drive chain tension with the rear suspension compressed halfway down.Get someone to sit on the bike.The play in the chain should be about 20-25mm.The rattle you hear will it be slapping on the swingarm.Hope this helps

Count the number of sprockets you have up front, then count the number you have in the rear, Multiply, 3 x 6 = 18 speeds. 3 up front, 6 in the rear, or 2 up front, 5 in the rear, 10 speed. Etc, they go as high as 21. You might only have one in the front.
To shift, you have to be peddling, get the bike going, put the chain on the middle or the biggest sprocket in the front, move the left thumb shifter to do this, do not let the chain rattle, make it a clean shift and don't let it klik or rub. Then put the chain on the biggest one in the rear , without any rubbing, chattering, slipping, etc,with the right shifter, now you are ready to take off easily, when you get going and the pedals get too easy and go faster, shift the rear to the next sprocket down, then again, then when you are coming to a stop, down shift the rear sprocket back to the biggest gear and you will be ready to take off again easily. A few tries, you will shifting like mario andretti. Hope this helps.

Check for loose heat shields the cover the exhaust. I find this is the source of many rattles. They are made of sheet metal and if they are not clip or tightened down the low vibration frequency when the car is running at slow speed will cause them the hit the exhaust pipe/ front mainfold.

THE RATTLING YOU HEAR AT LOW R'S IS MORE THAN LIKELY THE CAM CHAIN RATTLING. THE CHAIN TENSIONER IS ADJUSTABLE TO A DEGREE BUT A BIKE OF THIS AGE(IF OVER SAY 10000 MILES) MAY NEED A NEW CHAIN TO ALLEVIATE THIS PROBLEM. LOOSE CHAIN CAN CAUSE CAM TIMING TO VARIATE CAUSING A SLIGHT MISFIRE.
THIS MISFIRE COULD ALSO BE THE RESULT OF DIRTY CARBS. IF SO THEY WILL NEED CLEANING AND SYNCING.

You need to ajust the valves and the timing chain. Also have the timing look at.