changing sprocket...change chain?

[monk]

2001 400EX
I do mostly fairly aggressive woods riding, with some XC style racing.

I have yoshimura slip on, K&N, jetted to perfection (or close), Maxxis Raz'r tires (20" stock size, but they are 6 ply + "slime" in the rears).

I have good mid-top range gains with these new mods, but want/need more low torque. I am thinking 14t front sprocket is the answer for most of riding. I rarely get the chance to fully open throttle to full speed, but often come close, and still want all the speed I can get. Please correct me if I'm wrong.

1.) Should I also change the rear sprocket? If so, to larger, or smaller? Should I ONLY change the rear sprocket.

2.) When/if I change to a smaller sprocket siz on the front, do I need to remove a link in the chain, and vice-versa with a larger sprocket on the back?

3.) Any estimates on how much top end is lost with the 14t sprocket?

*15/38 are stock gear sizes*

im interested to see the answeres you get from this as I am kind of in the same situation. I hope you dont have to take any links out of the chain though cause some days I ride on the road to stores & stuff & sometime I am on the trails so it would be cool if I could just switch a 16 on one day & a 14 the next & thats all :cool: that was a runon sentence but i dont give a ****ing ****

[cals400ex]

a new chain is not needed with a smaller front sprocket. all you need to do is read your owners manual on how to adjust your chain. it is somewhat hard to explain. you will see 4 skrews on the rear of the swingarm that loosen with an allen wrench. you need to loosen all of these. then, just to the right of your rear sprocket you will see a little adjustment. you almost need to stick a skrewdriver or something similar in one of the notches or groves and turn up or down to loosen or tighten the chain. the procedures are in the manual. one tooth on the front is similar to 2.5 teeth on the rear. i would just buy the front first to see if you like it or not because its cheaper. you will lose a couple miles per hour with the 14 tooth. it is definately noticable when you race another bike in the upper gears. you will lose top speed. by the way, it is possible to switch from a 14 to a 16 without any modifications. with the 16, you will need to grind down your case saver a little bit to make it fit properly. i am running a 16 now and it works fine.

does a stock bike com with a case saver? i know this is a dumb question but I have seen them being sold on ebay soI dint really know. :confused:

[cals400ex]

yes it does. never run without a case saver. it is a little black piece of metal infront of the front sprocket. it is kind of hard to see behind the front chain guard. they do make aftermarket ones that are better looking and stronger.

[bmw500hp]

Originally posted by Crazy400exMan
does a stock bike com with a case saver? i know this is a dumb question but I have seen them being sold on ebay soI dint really know. :confused:

An aftermarket aluminum case save for 20 bucks or so is a good investment. More or less indespensible if you plan on switching the quads sprocket gearing on a regular basis.

Your new aluminum case saver will offer what appears to be "better case protection", "quicker and easier sprocket changes" as well as a neat trick look. :macho

[bmw500hp]

Originally posted by monk
2001 400EX

1.) Should I also change the rear sprocket? If so, to larger, or smaller? Should I ONLY change the rear sprocket.

2.) When/if I change to a smaller sprocket siz on the front, do I need to remove a link in the chain, and vice-versa with a larger sprocket on the back?

3.) Any estimates on how much top end is lost with the 14t sprocket?

*15/38 are stock gear sizes*

Monk..

First off this info is my choice for tight woods/hills etc in West Virginia terrain.

The first thing to do is try the 14th. in the front. If you are riding in the woods, you will notice considerable differences. If you feel that you lost more top speed then you like, go to a 37 on the rear. Personally, I like the tradeoffs in regards to the advantages of the 14. Lets review them.

The 2 main noticable tradeoffs are better throttle response off the lower rpms in 2nd and a more usable 3rd and 4th as the woods opens to a short field. The late hit of a 15/38 combo or even a 15/39 (not a bad combo either) causes me to ride the quad in the higher rpms in the woods to find the torque. 15/38 is all cool and actually fun but the "hit" caused more rider fatigue from the late power onset and the transition to hard breaking.

This fatigue ultimately leads (me) to decreased overall performance later in a 3 or 4 hour aggresive woods ride..

So far here are my personal choices for the 416 I would say the 22" rear tire combo ends up slightly higher in the overall ratios than the 20" rear. (BUT) the combo's seem to be the best for me.

23xct's / 22xct's - (14/39)
23xct's / 20xc's - (14/38)
22xc's / 20xcr's - (14-37)

:D

[monk]

Thanks, I am buying a 14t today.
BMW, if I ended up adding a 37t after to gain more top end...that would be smaller than stock. Smaller sprockets on front and back would be slower, right?

[cals400ex]

smaller sprocket infront = larger sprocket in rear = less top speed and more torque

[monk]

Sure Cals400ex, but he was saying that if the 14 alone was too much top end loss, try a 37 rear...which is 1 tooth less than the stock 38...I am just wondering how the 37 would impove top end over the stock 38 (which is obviously larger)?

Thanks everyone!

[cals400ex]

you won't notice much more top speed with the 37 over the 38. actually, you will still have a little more low end power than stock if you were even running 14/36.

[bmw500hp]

Originally posted by monk
Sure Cals400ex, but he was saying that if the 14 alone was too much top end loss, try a 37 rear...which is 1 tooth less than the stock 38...I am just wondering how the 37 would impove top end over the stock 38 (which is obviously larger)?

Thanks everyone!

Yup the 14/37 is good. Just a touch more on the top end. Like Cal said you might end up with a 14/36. The next micro step is back to a 15 with 39 rear.

Those last choices really boil down to the give and take. All those gearings have there place.