I have a 77 Moto Guzzi that I'm seriously considering fixing up and putting back on the road. There are a couple of mechanical issues, one of which is tires. The old rubber is a set of 15 year old bias tires, and I remember riding back from a rally and having major weave problems on milled roads. There was also an issue whenever I hit sections of 'erased' lane divider lines - the tires wanted to follow these irregularities in the pavement. Of course, my ST with radials exhibits NONE of these traits and rides over road defects with aplomb. (I've always been scrupulous about tire pressures and maintenance so I attribute the bike's instability to the bias tires.)
Tires for this bike (in Guzzi's recommended size) seem to be mostly bias type, and tend to have an 'aggressive' tread pattern - crosshatching would be how I would describe it compared to say a PR4's or Angel GT's mild wiggles or V's tread pattern. These latter patterns are what I call 'road tires'. Pardon my own nomenclature - I don't know if the industry describes tires this way but I hope it conveys to you what I mean.
My first question is this: Can I put a modern 'road' tread radial on an old Guzzi T3? What is the difference in handling that I can expect due to the tread pattern? What would be the difference that is due to the construction - radial vs. bias? Would the bike be unmanageable with these tires compared to the older bias types with that cross hatched tread pattern? I'm assuming that the stability of the tire has a lot more to do with the plies angle (radial vs. bias) than the tread pattern - am I right?
Second Question: Not all the mfrs offer the tires in Guzzi's recommended sizes. What difference in handling can I expect if I increase the rear tire size from 110/90 to a 120/90? This would be my only tire size change based on what is available today.
Tires for this bike (in Guzzi's recommended size) seem to be mostly bias type, and tend to have an 'aggressive' tread pattern - crosshatching would be how I would describe it compared to say a PR4's or Angel GT's mild wiggles or V's tread pattern. These latter patterns are what I call 'road tires'. Pardon my own nomenclature - I don't know if the industry describes tires this way but I hope it conveys to you what I mean.
My first question is this: Can I put a modern 'road' tread radial on an old Guzzi T3? What is the difference in handling that I can expect due to the tread pattern? What would be the difference that is due to the construction - radial vs. bias? Would the bike be unmanageable with these tires compared to the older bias types with that cross hatched tread pattern? I'm assuming that the stability of the tire has a lot more to do with the plies angle (radial vs. bias) than the tread pattern - am I right?
Second Question: Not all the mfrs offer the tires in Guzzi's recommended sizes. What difference in handling can I expect if I increase the rear tire size from 110/90 to a 120/90? This would be my only tire size change based on what is available today.