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cr500af

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Hi, i've just finished building my cr500af, it's a 2007 cr125 with an 01 500 engine.

Finally got a chance to take it out for a good ride, tight ST 2 gear mostly. The bike was wandering like i was riding sand. I've come to the conclusion it's rediculously undersprung.....

8kg engine increase after conversion, 95 kg rider. Stock kyb suspension/ spring rates....

Any recommendations would be greatly appreciated on getting it properly sprung and balanced, i believe the front bias is a little heavier too.

2007 cr125 / 500 af conversion at the moment it feels like riding in sand and i'm constantly trying to keep the front tracking straight in ruts/rocks/roots. it wants to follow everything

cheers Craig

DSCF1621.jpg

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Sounds like too much race sag is your current problem, but at your weight you need heavier springs than what the bike came with. For springs I'd check the Race Tech website (they have an spring application chart), or work with a local suspension guy. Sweet bike

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that motor has 2x the weight and power of the 125 plus the rake is probly steeper than hell. im sure its going to be squirly regardless what you do. its alittle late now but the cr250 chassis works good. looks like you did a nice job on the build though

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I'd put some showas on the front and have it set up for your bike and weight professionally. I'm partial to factory connection. Getting it set up right runs around a $1000 generally depending on how mice you want it. Biggest mistake of AF owners is not getting the suspension set up for that much power.

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Beautiful Bike!

I love the stock look, talk about a wolf in sheeps clothing-it still says 125r on the shrouds-nice!

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^^^^ What they said. But can i just add that it would be a great little talking point to leave them 125 stickers on the shrouds, if ya know what i mean.

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that motor has 2x the weight and power of the 125 plus the rake is probly steeper than hell. im sure its going to be squirly regardless what you do. its alittle late now but the cr250 chassis works good. looks like you did a nice job on the build though

I have the same chassis on my 500af and it's not squirley at all and turns like crazy. All I ride in is sand and it's very stable. If you have everything aligned properly in the conversion (assume you had to cut out everything from a couple inches forward of the pegs to well above the the top of the Y like mine) then it may be spring weight. At over 200 lbs if that is stock 125 suspension it is WAY under spring.

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btw, congrats on successfully doing the most difficult AF conversion, a gen 3 125.

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Hi, sorry i owe you guys an apology. The bike is a 125 however i used a 250 frame for the conversion.. All the 125 parts where swapped over.

I've got a rear spring sorted 5.6, a little heavier than wanted but should cope with the torque a little better, cant seem to find heavy front spring for KYB....

Looking around .49

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Hi, sorry i owe you guys an apology. The bike is a 125 however i used a 250 frame for the conversion.. All the 125 parts where swapped over.

I've got a rear spring sorted 5.6, a little heavier than wanted but should cope with the torque a little better, cant seem to find heavy front spring for KYB....

Looking around .49

I missed your weight? I go about 215 in gear and ride ST with 5.1 shock and .44 fronts. My race/rider sag is set at about 105mm, static I think was 20mm?

If your using the 250 chasis with KYB suspension, be careful of chain roller coming off the wishbone link. The KTB needs a smaller roller, the bike also sits higher. I didnt care for that so much BUT I like the KYB's better then the showa's.

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