Dirt Bike Modifications Forum

what can i do to get more bottom end and more torque out of a standard 03 kx125 to make it more hill climb friendly??

without loosing top end and the over rev? ?

thanks ,   anything to help stop it bogging so much and get out of the pissy bottom end , 

thanks

i wanted more bottom end in my cr85 so im putting in FMF torque reeds. hopefully that will work and wat kind of pipe u got on it.  IF u want bottom end get a fmf factory fatty and a shorty  

just got a standard pipe,  how much difference dose it make ,  will it be like oh *** that makes a big difference or what ??

or am i wasting my time,  i see that pipes ect will set me back quite a bit of cash so just want to know how much difference it will make

A FMF fatty and the shorty and reeds will help but that bike is made to ride up on the pipe (wrapped out) not have low end!  I put the pipe and reeds on a 02 YZ125 it helped from bottom to top but I dont think you will find the bottom end you are looking for in a 125. Hope this helps!!

Live life large ride ORANGE!!

Four strokes RULE!!!!

well i bought the reeds didnt put them in yet.  I want those pipes but it is alot of cash for me im only 14 and i dont have a job  

What  brand and style of reeds did you purchase?

Live life large ride ORANGE!!

Four strokes RULE!!!

i bought fmf torque reeds  

Good choice those will help and you should not need to rejet. Make sure you use the blue Locktite on the reed screws it will save you a costly top end!!

Live life large ride ORANGE!!

Four strokes RULE!!!

Im surprised that no one before me mentioned any thing about having it bored out to 144? I used to think that it was just a silly idea but the more that I look into boring two strokes it seems that it doesnt effect reciprocating mass as much as I thought and there by not effecting your top end power while allowing more production of torque at a reasonable price.

now we are starting to get some where, please tell me more...

what are the costs, and what sort of gains can you get???

finally an answer that is of some use, this had not even occured to me.

If you are talking about the 144, then the costs can range anywhere from $375 to $2000. Companies such as Moto 814, Max Power, RPMs, etc, all do the work. My company of choice is definitely Moto 814 if you care. As far as gains... the 144 will make 2 or 3 more peak horsepower than a 250f however the thumper still owns the low rpm range but that should be expected on a bike of twice the displacement. I've been told that the 144 is much more impressive on the track than on the dyno, so... if you would rather ride a fun, light, flickable, and easy to work on bike, spend the money to buy the 144. If you go to www.mawpower-engines.com you can contact them and ask for the new dyno charts of the 144. I used to have these charts but I accidentally deleted them out of my inbox (long story). The charts are a bit hard to read so if I have stated anything incorrectly, I apologize. Also wiseco will not be making 144cc (58.00) pistons for bikes older than 2004... at least not for the next few months. However, Max Power will create the 58.00 pistons for the older bikes for $110.00  

I have motorcycle machinist just like 25 miles away. They can do that. Check around first and save the core charges and shipping and crud, by having somebody local do it. Of course resourceful and amazing ebay sellers also do this, but not sure on legitamacy.  

I would check out Eric Gorr 's Forward Motion. $475 for the whole kit: Boring, plating, piston and rings, and gasket kit. Also Eric can set it up for better overall(mo Better everywhere), low-mid, or mid-top end power bands. Also he bores all 125's (all Brands) to use the wiseco 58mm piston made for the newer YZ's. So it does not matter if your bike is pre-2004.

Acoulple of things, though. He is going to be going overseas for the summer. He will be closing his current shop, and not be setting up his new shop until fall 2006. So you would have to send it in soon. Also his prices are due to increase 30%, I heard.

http://www.eric-gorr.com/

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