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Pushing through corners.

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Hi all. Im having a problem with understeer on a new to me very low hour 2010 YZ 250. Im set up all stock springs. Sag at 100mm. Forks with just caps poking out. And clickers are all 2 clicks tighter than stock. Im 6'2", 195. Where should I start to make the front end more responsive.

 

Thanks

-Dave

Edited by ADHDave

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Raise the forks in the triple clamps a bit. Ie. So the caps and a few mm of the forks are sticking out the top. That will make it turn faster, the way you have it will make it turn slower, good for sand but that's about it.

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Also turn in the fork rebound 2 clicks

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Got to ride an 09 YZ250 recently & still felt like the 02 & 04 models owned, but with better suspension.   I believe most of the issue is with the frame geometry as it's not designed to be a good turning bike & is more centered on the stability instead.  I had the same issue with the 02 & 04 models pushing in the corners & was never able to get it sorted out after trying different things like suspension set up, tires & air pressures.  From my understanding even though Yamaha went to AF in 05 it still shares the same geometry as the steel framed models.      

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My 06 was horrible till I got a offset axle

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Any changes in ride height between the rear and the front will change fork rake about 1 degree per inch difference so several things you can fuss with:

Raising the forks in the triples is an easy test, I'd go with 1/2" and see if that helps,  but the forks will probably hit the bars before 1/2".  That's 1/2 a degree.

Further forward on the bike while cornering will increase rake and weight the front wheel. Might be another 1/2 degree.

A different front tire may better suit your chassis and terrain, it sure made a difference on my CRF250X.

Increase front sag.

decrease rear sag.

Less front rebound, maybe more compression.

Opposite on the rear.

 

The last four may create other problems.

Edited by Chuck.

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As a test, take the bike out again and when going into a turn get all the way up on the gas tank.. I mean your man-bits should be kissing the gas cap. Now rail through a couple turns like that and see how it feels. I think you will be more than pleasantly surprised by the results. No, it's not comfortable the first time you try it, but after you get used to being that far forward on the bike, it will come naturally. I don't actually sit on the bike unless I'm laying the bike over in a turn. When coming in to a turn, I'm supporting my body weight on the pegs, hovering just above the seat. This crouched position lets me transition quickly to get up on the tank, and then you can easily load the outside peg while extending the inside leg and where your body is touching the tank is a second point of contact. I guarantee you that your bike will no longer push when going through turns. You will find that it turns much better & faster becausing you are planting the front wheel.  Speaking of speed you MUST maintain good speed through the turn with this method or you will fall to the inside of the turn. I'm by no means "fast" but this has really helped me with turns.

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I just set up a 2015 yzf250 for a fast A rider.  The rear was way over sprung and it was out of balance.  Installed a 5.2kg rear shock spring after a revalve.  Made the back end work great but made the front push a little.  Thought about dropping from the .46's to .45's but they don't have em.  So I was going to have to order .44's and run one of each.  Just for the heck of it I decided to stick in 1.7 kg ICS springs and it was the perfect thing.  Turns like a champ now.  He is 180 lbs.  Only issue we are having is a little too much activity with the back end on braking bumps.  mog suggested a softer high speed compression spring so I have that coming this week.  Loretta's qualifier this weekend so hope it is the ticket. 

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Any changes in ride height between the rear and the front will change fork rake about 1 degree per inch difference so several things you can fuss with:

Raising the forks in the triples is an easy test, I'd go with 1/2" and see if that helps,  but the forks will probably hit the bars before 1/2".  That's 1/2 a degree.

Further forward on the bike while cornering will increase rake and weight the front wheel. Might be another 1/2 degree.

A different front tire may better suit your chassis and terrain, it sure made a difference on my CRF250X.

Increase front sag.

decrease rear sag.

Less front rebound, maybe more compression.

Opposite on the rear.

 

The last four may create other problems.

 

mmmmm more front rebound....

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Also very sensitive to gearing if the gearing is too tall or your in 3rd when you should be in second it will understear

I run forks at 5mm plus cap (first line) sag 100-105 rebound fast both ends

But the tyre choice will affect it as well, there is 20mm dia difference between some brands marked the same size and that's a big geometry change on the yz

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Less front rebound, maybe more compression.

 

mmmmm more front rebound....

Good catch, I was thinking of keeping the front down in stroke for more rake but stated it backward.

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