Well, I finally got to test run my Immortal with the 18 tooth front sprocket installed, and let me tell you, it is fast, but after a couple power mods, it will easily be even faster. I have searched on here and elsewhere and I have never heard of anyone actually installing this sprocket on there, I thought possibly because Immortals aren't that common but.... now I know the real reason why. First of all, the install was not your simple pop the old one off pop the new one on; it required for me to first grind off a lot of metal on the tranny case there. You see, this sprocket is so much larger, the chain hits the tranny really badly. I had to painstakingly, with my dremel, grind off about an 1/8" of metal in one flat area, and then grind off about 3 "spokes" as I call them, in other areas where the chain has to have a clear path. On that flat area, the metal apparently is pretty thin, so I ended up CUTTING A SMALL HOLE IN THE TRANNY CASE!!! It was only about 1/16" in diameter but a hole is a hole and it scared me. I filled it in with some JB Weld, haha, but the rest of the metal there was still thin too so I pray to God that it doesn't break or get hot and fall apart sometime when I drop the clutch. Anyway, once that was done, got the chain cut to the right size but lost my masterlink.... hahaha, you know how that is, the thing is like one-of-a-kind with this chain (bought off pocketbikesunlimited.com) but after hours of searching I found one at ACE that would work, although it had just a tiny bit of play in it side to side (so far so good). Then the dang rear axle on one side turns out to be a *%$@# to move and adjust. BUT, all the work paid off and the chain actually went around without rubbing anything.
So I took it for a cruise and noticed right off the bat that my first gear was no longer too short to even use, and it actually served a good purpose now. Getting from 1-4 took longer than usual as I expected, but acceleration was still good. I noticed 4th was now like a dang overdrive. I went up the road and revved it up to 6k rpms (according to the tach which also seems rather inaccurate and jumpy) in 4th and my gps I had ziptied to the handlebars confirmed a respectable 48 mph after about a 1/4 mile run from a dead stop, and I know I could have hit 50 mph if I had more road. Keep in mind this thing is bone stock other than the gear and I have never even BEEN above 7k rpm because it seems like it won't rev any higher, in any gear. No matter the gear, there seems to be a lag between 6 and 7k rpms. Here is where I need your input. What mods should I do to make it rev a bit higher and get a little more hp? I was thinking exhaust first would free up a little, and then maybe port/polish? I don't know, give me some good ideas that don't cost me more than a pre-built race engine would. By the way, the stock speedometer is USELESS. It is accurate up to 20 mph and then it just goes WAY off, saying I was hitting 50 mph when I was at 30 according to GPS. When I actually was near 50, the needle was like pointing at the ground, haha. So I think I need a little more power now... get me started.
