Best performance upgrades for a 2 stroke?

GODMODE
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GODMODE
Edited Date/Time 1/27/2012 6:00pm
I'm on a 125, and have been since i started riding about 2 years ago, but i've gotten alooot faster, and the 125 is just holding me back powerwise against some of my friends on 250's and 450's, and i'm looking for any little edge i can get in our weekend battles (: haha

anyways, my bike already has a full fmf exhaust, that's an obvious upgrade, and i'm putting a new top end, and new reeds in it this month, what are some other upgrades that help a 2 stroke alot?
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mxb2
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mxb2 3/21/2011 12:08pm
3/21/2011 12:08pm
Make sure its geared right!, And if you can afford it run maxima 927, 40-1, c12 vp fuel. I m assuming your suspension is good?fresh tire also.
GODMODE
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GODMODE 3/21/2011 12:20pm
3/21/2011 12:20pm
well i ended up accidentally putting too heavy of an oil in my fork Tongue soo it's currently leaking a little bit (i got my dads oil and mine mixed up when i ordered it) but yuuup gotta fresh new tire on there. an as for gearing, it's geared stock right now which i think is 13-53, what's the best ratio if i want to keep it from dying on the bottom, but have a little more pull from my gears? is a 52 rear to low?
mxb2
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mxb2 3/21/2011 12:25pm
3/21/2011 12:25pm
Faster tracks or faster riders use a smaller rear sprocket, i.e. 48/49, you will get more bottom end on a bigger rear sprocket.
mxb2
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mxb2 3/21/2011 12:28pm
3/21/2011 12:28pm
What type of bike is it? year, make , model?

The Shop

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GODMODE
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GODMODE 3/21/2011 12:33pm
3/21/2011 12:33pm
it's an 04 cr 125, annd more bottom sounds nice, buut i can't find a 54 tooth rear anywhere, and it's already geared at 13-53 like i said, i was thinking about either going up a size on the front, or totally switching up the ratio on front and back
mxb2
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mxb2 3/21/2011 12:42pm
3/21/2011 12:42pm
13/53 should be good man, different exhausts also have different performance features also! FMF has different models! Do you have the factory fatty? and what type of silencer, i m a firm believer in the V force reeds/
GODMODE
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GODMODE 3/21/2011 12:51pm
3/21/2011 12:51pm
i have the sst, and the powercore 2, that's what i am planning on getting, or boyesen pro reeds
mxb2
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mxb2 3/21/2011 12:55pm
3/21/2011 12:55pm
factory fatty and shorty system is the best fmf system, and PC works pipe with shorty 304 silencer, V force reeds are the onlyone i would use. IMO.
clife
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clife 3/21/2011 1:11pm
3/21/2011 1:11pm
imo, v-forces reeds and proper jetting are the most important things on a 2 stroke. If you want more bottom then i would get away from the sst.
CamP
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CamP 3/21/2011 3:20pm
3/21/2011 3:20pm
None of the bolt-on crap will make your CR125 faster. You need to big bore it to a 144, have the cylinder ported and head reworked to make that bike fast.
mx295
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mx295 3/21/2011 3:33pm
3/21/2011 3:33pm Edited Date/Time 3/21/2011 7:43pm
Cheapest up grade you can do is Have the head milled .05mm and use 2 base gaskets, This adds compression and power through out the rpm range and matches the ports. Make sure the base gaskets are o.e.m. stock ones should be .04mm.. After market ones vary in thickness, Anywhere from .05-.07mm each.. If you add 2 that are o.e.m it will be .08mm.That is the thickness you want after you mill the head .05mm..Too thick gaskets can actually hurt performance because it takes away compression. We did this to the teams practice bikes and it made a big difference.
kx100getter
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kx100getter 3/21/2011 3:42pm
3/21/2011 3:42pm
Don't mean to steal this thread but is it normal for 2-strokes to have low power in lower RPM range? Sometimes if I am coming out of a corner (GODMODE, the corner before the finish line jump at T215) it feels like I am either in too high of a gear and sorta boggin out comin out of the corner up to the jump, or I am in High RPM's and it doesn't feel like I am accelarating
mx295
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mx295 3/21/2011 3:46pm
3/21/2011 3:46pm Edited Date/Time 3/21/2011 3:47pm
kx100getter wrote:
Don't mean to steal this thread but is it normal for 2-strokes to have low power in lower RPM range? Sometimes if I am coming out...
Don't mean to steal this thread but is it normal for 2-strokes to have low power in lower RPM range? Sometimes if I am coming out of a corner (GODMODE, the corner before the finish line jump at T215) it feels like I am either in too high of a gear and sorta boggin out comin out of the corner up to the jump, or I am in High RPM's and it doesn't feel like I am accelarating
2 strokes don't have torque like 4 strokes. So low RPMs mean low power.. If you're making RPMs but not really moving try checking your clutches plates. They might be worn and are slipping.
kx100getter
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kx100getter 3/21/2011 3:52pm
3/21/2011 3:52pm
Ok, It doesn't feel like they are slipping, more like I am at the top of the RPM's and have quit accelarating or I am sort of bogging down in too high of a gear. IDK, I will figure it out.
mx295
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mx295 3/21/2011 3:53pm
3/21/2011 3:53pm
kx100getter wrote:
Ok, It doesn't feel like they are slipping, more like I am at the top of the RPM's and have quit accelarating or I am sort...
Ok, It doesn't feel like they are slipping, more like I am at the top of the RPM's and have quit accelarating or I am sort of bogging down in too high of a gear. IDK, I will figure it out.
Air filter clean?
kx100getter
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kx100getter 3/21/2011 4:01pm
3/21/2011 4:01pm
About every other ride
mx295
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mx295 3/21/2011 4:02pm
3/21/2011 4:02pm
kx100getter wrote:
About every other ride
Have you checked your reeds?.. Could be cracked or worn
Craze
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Craze 3/21/2011 4:24pm
3/21/2011 4:24pm
You have to carry speed in & out of corners on a 125 and keep it in the "Meat" of the powerband

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chase383
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chase383 3/21/2011 6:08pm
3/21/2011 6:08pm
CamP wrote:
None of the bolt-on crap will make your CR125 faster. You need to big bore it to a 144, have the cylinder ported and head reworked...
None of the bolt-on crap will make your CR125 faster. You need to big bore it to a 144, have the cylinder ported and head reworked to make that bike fast.
X2
GODMODE
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GODMODE 3/21/2011 7:35pm
3/21/2011 7:35pm Edited Date/Time 3/21/2011 7:35pm
kx100getter wrote:
Don't mean to steal this thread but is it normal for 2-strokes to have low power in lower RPM range? Sometimes if I am coming out...
Don't mean to steal this thread but is it normal for 2-strokes to have low power in lower RPM range? Sometimes if I am coming out of a corner (GODMODE, the corner before the finish line jump at T215) it feels like I am either in too high of a gear and sorta boggin out comin out of the corner up to the jump, or I am in High RPM's and it doesn't feel like I am accelarating
pull in the clutch a tad bit in the higher gear ( i hit that jump in third) to keep it revved out through the corner, then seat bounce it. (: or take the inside line as hard as you can in the lower gear (second for me) and seat bounce
GODMODE
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GODMODE 3/21/2011 7:38pm
3/21/2011 7:38pm
mx295 wrote:
Cheapest up grade you can do is Have the head milled .05mm and use 2 base gaskets, This adds compression and power through out the rpm...
Cheapest up grade you can do is Have the head milled .05mm and use 2 base gaskets, This adds compression and power through out the rpm range and matches the ports. Make sure the base gaskets are o.e.m. stock ones should be .04mm.. After market ones vary in thickness, Anywhere from .05-.07mm each.. If you add 2 that are o.e.m it will be .08mm.That is the thickness you want after you mill the head .05mm..Too thick gaskets can actually hurt performance because it takes away compression. We did this to the teams practice bikes and it made a big difference.
oh and sorry for the double post, but my dad has that done to his bike i believe, and his friend who is a mechanic suggested that, so maybe when i put in the new top end in my bike in the next couple weeks i'll have that done!
bd
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bd 3/21/2011 8:46pm
3/21/2011 8:46pm
My 2004 Honda CR 125 is a dog compared to my 2006 YZ 125.

Put a 2005 to 2007 Honda CR 125 air boot on it and drill holes in the air box. That bike needs air.

Make sure its jetted perfectly
bd
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bd 3/21/2011 8:52pm
3/21/2011 8:52pm
See these links:

http://www.vitalmx.com/forums/Moto-Related,20/2004-Honda-CR-125,543763

http://motocross.transworld.net/1000067739/videos/video-2005-honda-cr12…

http://twostrokemotocross.com/2009/05/budget-racer-2001-honda-cr125/

http://www.maxrpms.net/shop/index.php/motorcycle-kits/mk-honda/cr125/cr…
CamP
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CamP 3/21/2011 9:05pm
3/21/2011 9:05pm
Eric Gorr does a 144 big bore for $500. That includes port work, head work and all parts/gaskets.

http://www.eric-gorr.com/mxlites.html
FIREfish148
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FIREfish148 3/21/2011 10:36pm
3/21/2011 10:36pm
I had a 2000 cr 125 and the thing was a turd I thought!! If I ever ride one now a days I know I can make it go pretty damn fast. The key honestly is to just have a good feel for your bike as far as the gearing, and don't be afraid to ring it out and control the power with your clutch.
54 tooth rear sprocket? you gotta be kiddin dude.
DBerg
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DBerg 3/21/2011 11:43pm
3/21/2011 11:43pm
The V-Force reed valve is a phenomenal bolt on. You can truly feel the difference. The throttle feels more responsive and crisp and it really smooths the power out. The best part is it's only $150. As for gearing, I would def not go with a 54 rear sprocket. I run a 13-50 and I'm pretty happy with it. That was the most commonly recommended gearing when I was asking around. I'm personally saving up to get some suspension work done.
kx100getter - You just gotta work the clutch and keep the rpms up.
johnnyg
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johnnyg 3/22/2011 2:42pm
3/22/2011 2:42pm
Ditto on EGorr had him doing my kxs. great work have him set the squish too.

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