I actually haven't figured it out yet unfortunately. To me it looks as though the chain guide just needs to be dropped half an inch or an inch. If you look at the chain guide it attaches to a quarter inch piece of aluminum with three holes in it I believe. Simply making a one inch extension for that out of quarter inch aluminum or Steel would drop it down enough to probably work just fine. I have a machine shop at work but we've been really busy so I haven't been able to Fab one up real quick. Hopefully in the next week or so and I'll take a picture of then chili and post my results. I know some people have run these sprockets and I was hoping to hear from some of them but I just haven't had any luck yet with it. I'm not going to risk running no chain guard. And the 51 tooth will hit the stockyard. Also with a 13 tooth front sprocket I needed the slightly longer chain to fit 251 and obviously the 53 that I really wanted to put on it