I have been running a 14 40 sprocket and I just bought a 15 because I have plenty of bottom end power just wanted a little more legs to keep those damn 4 strokes in my dust where they belong. Any experience out there.
sproket size...
- Thread starter scotj77
- Start date
u might have to grind the outside of the case but not sure but it will be a tight fit.let me know how this works and take some pics
I haven't put it on yet it is just one of many add on's I am doing while I rebuild this thing again. I am begining to think that my hobby is two stroke rebuilding not 4wheelin. Back to the topic though, my buddy just bought one and said with one quick smack to the cover and it popped right on. If it rubs a little it won't rub for long before it makes its self a new home.
exactly what I thought!!... I have a 15 39 on my 240.. it didn't quite want to fit at first (the cover) ..... didn't want to take off either, so I just went ahead and gave her hell so the chain would cut a groove in the plastic.. seemed to work great after the first take off! but less than 20 min later, I was dead in my tracks.. because the clutch busted to pieces... but it was already easy to push by then. so, I don't know if doing that was related to the clutch failure... but I would advise taking the time to shave it before hand just to be safe..
another point. if you plan on doing heavy hill or sand dune riding often, I wouldn't recommend going 15.. It helps with top end on the street, but is hard for my blaster to pull in high gear pulling my 235lbs. in the sand.. lol
another point. if you plan on doing heavy hill or sand dune riding often, I wouldn't recommend going 15.. It helps with top end on the street, but is hard for my blaster to pull in high gear pulling my 235lbs. in the sand.. lol
Good to know about the clutch thing. Seems weird but I will def take it in to consideration before I put it on. I do a lot of mid range riding and I live in Fl so no sand dunes that you can "legally" ride on. I am also wondering witch way does the rear sprocket work the higher or lower the number what is the out come. I have a 40 right now so which direction would i need to go to get more bottom end if don't like the 15-40 ratio.
here's how this works......
Gear ratios are calculated by taking the number of teeth on the rear sprocket and dividing by the number of teeth on the front sprocket.
The lower this number is numerically, the less initial take off you will have, but you will gain top speed. This is referred to as a "high" gear ratio.
When this number his higher, it is reffered to as a lower ratio.
Essentially, the closer you get to 0, the more top speed you will have, at the expense of acceleration
changing rear tire diameter also technically affects your gear ratio, taller tires are more speed, smaller tires are more acceleration, just like when you change the size of the sprocket.
now lets apply this.....
stock you have a 13t front, and a 40t rear. to figure out gear ratio
rear tooth/front tooth=gear ratio
40/13=3.08
change the front sprocket to a 14t and we have this:
40/14=2.86
this is a pretty substantial change in the scope of things by just changing 1 tooth
now lets play with the rear sprocket.....
stock front with 13t, and a rear sprocket with 39t.
39/13= 3
this is a very very small change.
It comes out that for every tooth you add or subtract from the front sprocket, you subtract or add 3 teeth to the rear.
40/14=3.86
37/13=3.85
basically if you are looking for a large change in your gearing then change the front, as far as i know the smallest rear sprocket you can get for a blaster is a 38t. so large changes can only be done with the front, use the rear to fine tune. for most people a 14/40 seems to be the sweet spot
Gear ratios are calculated by taking the number of teeth on the rear sprocket and dividing by the number of teeth on the front sprocket.
The lower this number is numerically, the less initial take off you will have, but you will gain top speed. This is referred to as a "high" gear ratio.
When this number his higher, it is reffered to as a lower ratio.
Essentially, the closer you get to 0, the more top speed you will have, at the expense of acceleration
changing rear tire diameter also technically affects your gear ratio, taller tires are more speed, smaller tires are more acceleration, just like when you change the size of the sprocket.
now lets apply this.....
stock you have a 13t front, and a 40t rear. to figure out gear ratio
rear tooth/front tooth=gear ratio
40/13=3.08
change the front sprocket to a 14t and we have this:
40/14=2.86
this is a pretty substantial change in the scope of things by just changing 1 tooth
now lets play with the rear sprocket.....
stock front with 13t, and a rear sprocket with 39t.
39/13= 3
this is a very very small change.
It comes out that for every tooth you add or subtract from the front sprocket, you subtract or add 3 teeth to the rear.
40/14=3.86
37/13=3.85
basically if you are looking for a large change in your gearing then change the front, as far as i know the smallest rear sprocket you can get for a blaster is a 38t. so large changes can only be done with the front, use the rear to fine tune. for most people a 14/40 seems to be the sweet spot
nicely said brando take some rep.well i take the rep thing back it wont let me
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i have a 15 tooth. ppl said it wouldnt work. i cut off my sprocket guard from the stator cover. then the chain wore a slit in my case but so far so good
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