<font color="blue"> The spacers are for a friend, but he has R4 tires. Does it still require the spacers with R4's? </font>
I don't use spacer on my R4s. Now I have 2-link ladder chains and good tensioners. I think my chains and tensioners cost around $250 for the set. Cheaper than the spacers would cost!
Anyway, a more aggressive chain might require spacers. I don't know.
Below is a pic I posted in another thread. R4s, tensioners, no spacers, no problem in my case. As is often pointed out, half the cross links do ride down between the lugs. I guess this may always be the case if you snug up your ladder chains. I still get ample traction from the chain crosses on top of each lug.
I doubt that you could run chains on the
B7800/2910 loose though [without spacers], like some people prefer to do. With the chains tight I have about 1/2 inch clearance at the fender bolts, if I remember right.
Since the chains + tensioners cost less than the spacers, I would try the chains first and see if I needed the spacers...your friend may not, since I don't...