KZ305 sprocket question

Everything I found online says my stock KZ305 has 15T front and 33T rear sprockets. I am running at 6000RPM at 55MPH. I'd like to tone that down a bit. I found a 16T front sprocket from Z1 for $10.99. Based on fomulas I found, that'll get it down from 6000 to about 5600. Is there any way to get that down a little bit more closer to 5000? I'm not concerned about the giddy up off the line, I'm a gas thrifty rider and I want economy over speed, after all it IS only a 305 so I can't expect it to launch like a rocket anyway!!!

The sprocket from a Z-1 will not work it is a totally different mounting system. The 305 uses the same type of attachment system as the 550 though so it is possible that might work. I have both a 305 and several 550's so I'll check it later and let you know for sure. I don't think you will want to go more than 1 tooth up though going up 2 will put the gearing way too high I'm afraid.

Okay I just checked this out. The stock sprocket from an 81 550 LTD is a 16 tooth and it will bolt right on with no problem the countershaft is the same spline and uses the retainer that is held on with 2 6mm bolts. Just to make sure I ran the chain around it to make sure it wouldn't bind on the cover or anything seems like it will work ok, it is a tight fit so using anything bigger is out of the question but this should drop your RPM's a bit. Now we both know.

DOH.... I just re read your original post and noticed you were talking about Z-1 Ent. and not a Z-1 model.....:blush: :blush: :blush: Never mind!

cant deny the effort though gringo

Yeah, I was talking about Z1 ent... thanks for the stellar effort though!

Just to follow up and left everyone know, I received the new 16T sprocket from Z1 Ent. and installed it last night and went for a ride. It makes a big difference actually. It's barely noticable "off the line", but 6th gear is nice, it's basically like having 7th gear. My bike now does 60MPH at just under 6000 RPM's. I went up some hills and it didn't really bog down too much more than it did before. Just going 65 before to keep from getting ran over on the highway was taching 7500 before, which made me nervous that the engine was just going to fly apart and take my legs with it. Thanks for all the help!!!!

If you need to you can always go a couple teeth smaller in the rear without having to shorten the chain.

I haven't found anything smaller than the stock 33T for the rear though, I've found bigger, but not smaller. I wouldn't go more than 1 tooth though, it might bog down too much.

Sorner thanks for the followup. I don't ever see myself riding my 305 on the highway (too many other bikes that work better for that)it still is good info to know. My stepson is only 13 so it will be a few more years before he can legally ride but possibly then this might be a good mod to make.

I don't either, if I ever go on the highway it's just to go one or two exits just to avoid traffic... but if I do that I don't want to get run over! LOL! I don't know how far torn apart your 305 is, but I noticed a metal shield around the housing outside the sprocket on mine, I dont know what's behind it but if that can be removed it would take a 17T sprocket on the front. I'm not going to get into that because I'm satisfied with the results going to the 16T.

Removing that little shield would not be a good thing to do because in the event you snap your chain it could really damage the crankcase. My 305 is actually pretty much all together I'm not too sure yet if I can get it out of the basement that way though. I may have to take it apart, carry it up and re assemble it again :pinch: . Here is a pic as it currently sits.

Post edited by: The Gringo, at: 2007/06/26 09:00