cr125 power up

Just need to know if any one has been able to make a useable powerspread from a CR125 2005 is at the moment it has been professionally ported, jetted and compression has been also raised, runs a pc pipe as well and its still a there anyway possible to get a yz like power spread, i didn't really want to trade it in on a yz cause it handles so sweet and i'd have to get new gear as well to go with a blue

Any one tried a big bore kit...

What are you running for jets?

Stock reeds?

Compression at?

Gearing? 14/53

What type of porting? Low,Mid,Top end?

If your interested in a Big Bore Kit let me know I'll Email you cost and dyno sheet.

Thanks Gene


get a new top end, v-forces reeds, bore it to a 144 and stroke it, or just get a 134, change the gearing for your riding, power now and power now +, port and polish the carb out, clean the carb

it has been ported for more bottom end......

don't get me wrong the bike is a big improvement over the stocker,but the powerband is still to narrow for my liking and after riding a dead stock 05 yamie on the weekend i think the motor in it was much more useable then my mine even after spending all that money on it.

Mods so far

PC Pipe

v-force reeds

Compression raised -not sure of the actual compression


Gearing 13-54

What should i do next

1. go the big bore

2. sell it, buy a Yamie 125 plus matching gear

3. keep it as is and continue to whinge every time i take it out for a ride

2. sell it, buy a Yamie 125 plus matching gear

:thumbsup::lame: or ktm or suzuki..

i rode a yz there not that fast my cr is faster, i bet this is a joke and you just made up this sceen name to dis Honda, i bet you dont even have a cr and i bet you have a yz and you want your yz to look good or something :thumbsup:

i rode a yz there not that fast my cr is faster, i bet this is a joke and you just made up this sceen name to dis Honda, i bet you dont even have a cr and i bet you have a yz and you want your yz to look good or something :thumbsup:

or, i think you're mad cuz yamaha is #1 !!!!!!! :lame:

I don't think so, red is def my fav bike colour,

I also have a 2006 CRF250 and with the carbi mods posted on this site and a 04 cam you couldn't ask for a better bike,

even looking at the world through red coloured glasses there is no way you can put a CR125 motor on the same page as a yz125 one....

or, i think you're mad cuz yamaha is #1 !!!!!!! :thumbsup:

then why did i buy a honda if yamaha is better? :lame:

I am all for honda but i have to admit that my cr125 04 is not as fast as the yamaha or the suzuki, hate to say it :thumbsup:

You must weigh alot, my 05 is fast stock. I pwn 40 year old noobs on it. They ride kawi 250's.

get a cr250 :thumbsup:

i have riding over 20 125's in my life and the crs are just as fast as all of them. i own a KTM 2004 125sx and a 03 cr125, and my cr smoked it in a drag in a strait line on a paved rode both when there stock Honda won and when there modded and the honda smoke it mid to top and low end was the same with same pound riders on them..

I just put a Kx exspansion pipe on our 02 cr125 and wow did it ever make a difference . I have a PC and Fmf but he kx stocker blows them both away.. Just ask Faded.

I just put a Kx exspansion pipe on our 02 cr125 and wow did it ever make a difference . I have a PC and Fmf but he kx stocker blows them both away.. Just ask Faded.

how dose a kx pipe fit the cr?

Mine is a 144 with porting, and it made a difference. But I also used a Suzuki RM piston instead of a Honda piston. The wrist pin is lower which lets the piston stick out the cylinder, and cleans up the fuzzy port timing. The head has to be step cut to compensate for the higher piston height. The final thing that woke that beast up was the PSI carburetor. The bore is diamond shape. It keeps the velocity fast all the way until the last bit of throttle hits the wide top area. The main jet, needle and idle circuit are all adjustable from the outside. That thing pulls really hard, and did I mention it's lighter than my 450.

Put a kx 125 pipe on it.04,05 pipe. I here it works good. Then go to a 144 kit if you want more power.

I just put a Kx exspansion pipe on our 02 cr125 and wow did it ever make a difference . I have a PC and Fmf but he kx stocker blows them both away.. Just ask Faded.

What Year KX pipe for 02 CR? Does it improve bottom end?

ok man.. we all know that honda is not known for there 125 motors!!! but they handle better then any other 125.. so either have the power of a yami have the handleing of the honda!! if you could really ride you could beat the yami through corners!!:applause: and the honda is not that much slower!! it just hits the power band at a different time in the RPM range!! (later) so get over your self:bonk: !!! and stop bashing honda!!

why is every one trying to get bottom end out of 125s? i wish i had an 05 or up af frame to put my peaky 1985 125 motor in. then i could realy fly. it seems smaller 2 smokes just dont have strong enough induction to make much (any) bottom end. they have to spin inorder to make some hp. my oldy spanked an 04 cr125. now if i could just get it to stop shaking its head...

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