Goodyears seem to leak more air through the sidewall then the M/T. I know this from personal experience. Fill it with air and keep checking it. I would have to add air before every run. M/T would hold air better for me. M/T slicks need a harder burn-out for the first couple and then it doesn't seem to need as much after that. They seem to last longer then the Goodyears also. Lots depends on the rubber compound though. Not sure if the M/T can be bought in different compounds but the Goodyears used to. For the most part, M/T are the ones you see most of. 17" M/T should give better MPH numbers as they will grow more on top end. Some racers have had to give extra clearance then they ran with a 18". I have read where 17" slicks give better e.t. but the 18" react faster because the sidewalls on the 18" don't "wad" up as much as the 17" before moving the bike. Think wrinklewall and how they wrinkle up and then once wadded up, they shoot the bike out. The 18" will plant and get the bike moving but not as hard. Not sure if you can get the 5.5 in different sizes though. From my experience, I will run M/T all the time. Better availability, more information on how they work, holds air longer and generally are cheaper then the Goodyears. Only thing I have heard about the Goodyear slick that is better then the M/T is that they are stickier but with that feature, they don't last as long. Also, the heavier your bike/rider combo, the harder the compound you want and that is where the M/T should be better for most racers. One racer commented that both tires will e.t. close to the same after chassis is tuned to the tire but the M/T lasted much longer. I have heard some say they will go through 2-3 M/T a year while going through 6-7 Goodyears. Have a lot of money for tires?
1980 LTD (changed over the years), 1979 LTD (being rebuilt), 1977 KZ turbo and various KZ's in various states of build. KLX110
