justin_o_guy2 wrote on 06/10/22 at 13:20:32:Dave?
Daves not here, man..
Here I am!!!!
An 18" rim can work without a swingarm notch - it really depends on the tire size. My first rear rim had a 18x2.50 rim.....and I followed the RYCA lead and installed a 130/70-18 tire with a frame notch because everybody said so. I discovered the 130 tire is not designed to fit a 2.50" wide rim, and tire tread profile is distorted and made to be too round.......it causes the center of the tire to wear quickly and you never get over onto the side tread as it is rolled over too far. A 130-70-18 tire squeezed onto a 2.50" rim resulted in a tire that had a tread width of only 116mm.
I laced up another wheel with a 3.50" wide rim and the 130/70-18 tire fits it nicely - it is far more rubber than the Savage really needs but looks good. The tread width is very close to the claimed 130mm.
On the 2.50" rim I installed a 110/80-18 tire and used it for a few summers. The tire looked a bit skinny and the tread width measured 108mm. The tire worked just fine and I never experienced any problems with a lack of traction and never felt anything unusual. (Early Norton, Triumph, BMW and similar motorcycles all used tires that were this skinny.....and they often weighed more and had twice the HP).
The 3.50" rim and 130/70-18 tire looks nice if you are used to seeing wide rear rims and tires on modern bikes and it works well. The extra weight of the wider tire is noticeable when you are mounting the tire/wheel assembly - but not so much while riding.
If you are going to run a 2.50" wide rear rim - I believe a 120/80-18 tire may be the proper size to use. It will have plenty of rubber for the savage and it's low HP and weight.
I am still running my notched swingarm - but I don't need it. If you install a Kawasaki front pulley it will pull the rear tire forward all the way to the forward end of the adjustment slot and depending on the diameter of the tire you are using - you may need a notch with the Kawasaki pulley. I am now running a Kawasaki front and rear pulley and that moves the axle all the way to the back of the adjustment slot and provides plenty of room for the tire to clear the swingarm.
Summary.......The swingarm notch really depends on the tire size and look you are after and drive pulley you use.