I am building a 300ex . It has 400ex A-arms and shocks , a 350x swingarm and shock with an extended axle , An 11 to 1 wiseco piston bored 80 over to make it a true 300, a hot cam , 400ex carb, the head is ported and polished, it has a 450r honda headpipe and muffler I fabed to fit , an aftermarket cdi box and coil and a Barnett clutch . I am ready to order my chain and sprocket . I think stock is 13 / 38 . Some other posts say to gear up for a modified 300 and that one tooth in the front equals three in the back . I would rather do a rear sprocket than a front because of case clearance. So do I go to a 40 tooth or a 36 tooth in the rear . I mainly ride in the woods in Ohio but still like to drag race every now and then . I would like to be able to wheelie over stuff with ease and have some extra topend . What would be the best compromise to get the best of both worlds . Does anyone know what sprockets national bikes run? thanks

 

My experience has been that one can not go to large in back, becasue of clearance issues with skid plates, etc. You need ground clearance in the woods, so lowering a skid plate isn't going to be an option.

 

Considering it's ver hopped up, i would gear it, from stock, towards speed, so larger in front or smaller in back.

 

in my opinion if you have 22 inch tires you should go 13/37 if you have 20 inch tires you should go 14-36 and if you have 18inch tires which i doubt you do go with 13/34 i think that will get you in the ballpark that you want to be in

 

I forgot to mention I am running a 20" tire. I have some rear tires from a KFX400 . I was leaning towards going 13/36 .I dont want to run a 14 tooth in the front because I dont think my case saver will fit with a 14 tooth . I am torn between 13/36 and 13/37 . I purchased a new chain and sprockets for my wifes warrior a few months ago and went with a smaller front sprocket and a stock size rear and could not believe how much it helped . I gave up some topend but it is alot better in the woods ., Thanks in advance for any help good luck with your racing season 450r

 

A 14 will fit in front but you have to grind some of the case saver away or cut it in half and just use the top half. That's the way mine is.

 

oh 14 in the front fits on my 300ex i didn't have to modify it at all what year is your guys 300's my is a 97 but bought new in 99

 

mine is a 1999 . I have been working on it for a long time. I put 400ex A-arms and shocks on it . A 350x rear swingarm and shock and an extended axle . I hope to put it all together soon I am waiting to get the frame and swingarm / A-arms back from a guy thats painting it for me . The only thing I dont have yet is my chain and sprockets . I am was thinking about buying an X chain ? I think thats what it was called . I was looking on the sprocket center web site. Any feedback about chains and sprockets ? They have an alloy rear or a steel rear other than weight whats the difference ? How much longer will the steel sprocket last ? The alloy sprocket is only $20.00 more . I wil try to post pics . thanks Bob

 

i like the gold chain (can't remember the name) looks goods and lasts a long time.