More info on car tires .

I don’t know if the General tire will work that well for you. I think it is just the width and how hard the tire is.
On the pavement, I have no problem dragging floorboards in a corner.
The only place it wants to pull the bike is when on dirt roads with ruts. I am not talking small ruts either; the ones left by trucks become a challenge.
I always play around with it on the street in the paved ruts and transitioning from pavement to gravel on the road is not a problem.
I say look for a high performance soft sticky tire.
I felt a similar thing with a Mickey Thomson front drag radial on my Beemer. When I took it off and went to the BFGoodrich Radial TA. It was the difference between night and day. The drag radial was 2 ply and the TA was 1 ply.

The general Altimax he used doesn't come in a 245/45-18, only the G-Max AS-03 that I put on does, and it is not $70.00, But it is still a lot cheaper than the MC tire.

The 40 did not fit width wise and rubbed the front swing arm and belt guards, the 45 just barely fit. The sidewalls of the 40 car tire are 1 5/8" wider and extends out from the rims side. If you look at the mc tire, it is flush with the rim.
My bike is stock when it comes to the suspension.
Go back to the pics I put on the Dark side Page you can see how close the 45 is.

The picture is of the bottom guard and it has about 1/6-3/32” clearance.
I know I can take the back plastic plate fender off, but I am leaving it on because I don't stop for rain like a lot of Harley riders do. I don't need extra back spray from the rear tire.

How wide is the 250? The 245/40-18 is 9 7/8" wide. With the 30-tooth pulley and no guards, it may fit. It would give the bike one **** of an Overdrive. The 45 I am using is about 8 ¼” wide.