Texasscott, this is why people said that it would be good to see me post. I watch combustion happen in real time on a scope every day. Pinging is just as I said before. "Pinging is ignition that has spread to the edge of the combustion chamber and is traveling down the cylinder and meets the piston on it's way up. I regularly diagnose dead engines. I am really good at what I do. I just bought this bike from a friend. There's a reason why I always hated large V- Twins. I am totally correct in that the engine IS PINGING! I have heard someone else calling it," piston slap". I just purchased this bike. I didn't design it. I have now rode 7 other bikes. They all do it. It is a design flaw. This is the reason why I always bought four cylinder inline engines that don't make this noise. I have now pulled apart a Roadie with 68,000 miles and the cylinders are TOTALLY tapered. The noises that I hear are, "piston slap", AKA pinging. I really tested the engine. Yamaha should have included knock sensor in their design. My engine regularly knocks. I don't think this. I Know this. My bike is totally stock except for the stage one jet kit. I reverted to the stock jetting and that would just reduce engine life quicker. Yamaha just decided that 100k was a good time for the engine to die. Harley Davidson seems to agree. The engine pings from day one. I still like the bike though and I will do just what I said. I will re-gear the bike so that I am in the zone in which it doesn't ping. Many people go up in gearing and enup with a bike that isn't happy at a 100 mph. I got this bike used at $5500. I'm! not happy with a bike that won't go 155. This is a good bike to take my woman on so I will re-gear it and stay in lower gears to keep it alive to 150k. I'm an engineer who will ride this torquey bike without listening to the pinging till I sell it.

What RPM is the minimum in any gear to prevent pinging? Thanks

Do you recommend high octane gas with octane booster for a stock Roadstar engine? I've been running 87 octane since day one and it has performed great. What are the advantages of such high octane in these engines?

pc_doc, pinging/detonation is exactly as I described. There are no design flaws in the Road Star engine that I know of and it, with proper care, will last well over 100,000 miles. The longest I know of is 230.000 miles using Yamalube. I have never heard of cylinders being tapered on bikes taken apart and described here. As a matter of fact everyone seems to have been surprised that the honing marks from the factory were still there. The Nikasil coating on the cylinder walls is very hard and difficult to wear away.

One thing's for sure, there's something going on with your bike that I don't think anyone else here has heard before.

Silence! All of you! The engineer that “KNOWS” has spoken.

Get over yourself. There’s millions of miles represented by members here. Many have well over 100K on their bikes, and I doubt Yamaha spent upward of 20 million in development to give us flawed motors that knock and ping all the time. Are there issues with these motors occasionally? Yes, but holed pistons and seized rings are not among them. You have yourself a nice day.

Why did you buy a Road Star if YOU knew there was a flawed engine in them?

So I took 3 different knock sensors and had enough duct tape and wires taped to the bike that it looked like spaghetti. I was down below an eighth of a tank so I went down and filled the bike with regular gas. I took it out and ran it 20 miles up steeper sections of the county and kept switching channels. Damn this thing can make some noises when you luggage it (but I still like the exhaust tone). When I rode like I normally do and kept the revs above 2300, (I have my dirt bike tach hooked up to it and I might just leave it there) the engine is remarkably quiet. As it turns out a lot of what the knock sensor was picking up as pinging is coming from the primary chain area and echoing through the engine. I manipulated the tps and the results were less performance and MORE noises. I reset the tps and added a gallon of 117 octane fuel and the noises were less, (probably due to the tps being correct) but almost exactly the same telling me that I was incorrectly thinking that the noises that I was hearing was a ping. I rigged another bike with 47,000 miles with the same sensor on the primary chain area and it was almost exactly the same frequency which sort of tells me that it's not wearing out very quickly. I will still use premium fuel because I use premium in all of my vehicles. The noises still make me sort of crazy so I am going to re-gear it a bit. It seems, "happier" when I am at 75 in fourth and the throttle response to pass cars from 75- 90 is much better in fourth and I feel that the engine has more than enough torque to support a lower ratio gear. This would have me in the RPM range that I want in the areas where I ride, (one of the bikes had a 31 tooth gear and I though it doesn't make the noises at 75 any more in fifth the throttle response in a roll on wasn't like that of fourth gear and his bike is revving to high to cruise fourth at 75 which is where I normally cruise) I do appreciate the advice that I received and I apologise for being so damned stubborn. Joe

I've owned two roadstars and occassionaly heard pingng because the 01 had 10.5 pistons and for good reason didn't like shitty fuel. And I KNOW what no pinging sounds like.

Not to stir the pot but my bike prefers 87 octane unless it's really hot out. It cranks for twice as long before firing up when cold starting in the mornings with the higher octane and louder engine noises at low rims. The previous owner said he only used premium fuel so that is why I tried it for myself, I have the stock computer so I never changed spark timing at all, just ran 4 tanks of premium to try for myself. I put 91 octane to store for winter because I was told 91 has no ethanol here. Ps, high octane is 104 here. We have 87, 91, 104.

What primary chain are you talking about? I thought it was gear driven?



[Rb]pc_doc wrote:[/b]
So I took 3 different knock sensors and had enough duct tape and wires taped to the bike that it looked like spaghetti. I was down below an eighth of a tank so I went down and filled the bike with regular gas. I took it out and ran it 20 miles up steeper sections of the county and kept switching channels. Damn this thing can make some noises when you luggage it (but I still like the exhaust tone). When I rode like I normally do and kept the revs above 2300, (I have my dirt bike tach hooked up to it and I might just leave it there) the engine is remarkably quiet. As it turns out a lot of what the knock sensor was picking up as pinging is coming from the primary chain area and echoing through the engine. I manipulated the tps and the results were less performance and MORE noises. I reset the tps and added a gallon of 117 octane fuel and the noises were less, (probably due to the tps being correct) but almost exactly the same telling me that I was incorrectly thinking that the noises that I was hearing was a ping. I rigged another bike with 47,000 miles with the same sensor on the primary chain area and it was almost exactly the same frequency which sort of tells me that it's not wearing out very quickly. I will still use premium fuel because I use premium in all of my vehicles. The noises still make me sort of crazy so I am going to re-gear it a bit. It seems, "happier" when I am at 75 in fourth and the throttle response to pass cars from 75- 90 is much better in fourth and I feel that the engine has more than enough torque to support a lower ratio gear. This would have me in the RPM range that I want in the areas where I ride, (one of the bikes had a 31 tooth gear and I though it doesn't make the noises at 75 any more in fifth the throttle response in a roll on wasn't like that of fourth gear and his bike is revving to high to cruise fourth at 75 which is where I normally cruise) I do appreciate the advice that I received and I apologise for being so damned stubborn. Joe