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Less Anti-Squat?

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I am really getting to know and like my 2011 RMZ, but it still feels to me like it has too much Anti-Squat.  I came from riding YZFs, and could squeeze with the knees, twist, and manual over stuff letting the rear shock suck up chop and acceleration bumps.  The front comes up really easy.   No such luck on the RMZ.  The front does not come up anything close to as easy.  I think it is a very minor geometry issue...namely, the bike needs less Anti-Squat.  Unless you have a CMM Machine and some large machine tools to remachine frame pivot locations, etc, there is not a lot you can do to change AS.    About all you can do is Swingarm/wheel location and gearing.  Has anyone played with gearing to change AS dynamics?  For instance, small small sprockets...say 12/46 will give near the stock ratio, but reduces the tangent line (chain) angle and move the Anti-Squat intersection quite a bit.  This will make the bike lower in the rear more under throttle, etc.

 

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I'd expect a larger front and smaller rear to induce more squat under power.

Since you've tried the axle forward and I assume everything with the damper adjustments, and rear sag, the only other ideas i have are:

Bars mounted aft.

Softer rear spring, possibly also combined with a less progressive linkage and firmer shock HSC to compensate on big hits.

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I know exactly what you mean as I too was looking for more squat out of the bike. It allows us to do everything you describe and is the anti-stinkbug that gives confidence. I have come full circle with this bike (12) and right now I am at 175-180 lbs. I have .49 springs in front and I have the ride eng. Link with a 5.7 eibach shock spring. Last week factory connection revalved the bike for a mid pack B Vet MXer and they took out the modified showa stock piston I was using and actually put the x-ring piston back in.

So yesterday I went to a jumpy mx track and the conditions were perfect. The bike tracked smooth and could turn like a Suzuki but what I was really happy with was the shock....

I had traction for days and the rear end had the sensation of staying down and in a sort of "ready" position for that mid to exit of turns....it wouldn't come unsettled and you could really trust it in the longer turns.....then on exit it just clawed forward. Lets just say that after a few seasons on the bike I feel I do need the bigger front rotor now because I am no longer afraid to clamp on it and unsettle the rear when I am bounding toward a corner in a slanted position.

FC told me to run the 5.8 but agreed the 5.7 would work. They also said to test the stock link but I have been through this so many times and I think the link will stay on.

Food for thought.

Edited by mikerides33

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I'd expect a larger front and smaller rear to induce more squat under power.

Since you've tried the axle forward and I assume everything with the damper adjustments, and rear sag, the only other ideas i have are:

Bars mounted aft.

Softer rear spring, possibly also combined with a less progressive linkage and firmer shock HSC to compensate on big hits.

 

You are correct about the larger front and smaller rear, but that jacks up the gearing.  The rear makes the much bigger difference in the instantaneous center point, so you can drop them both, hold the gear ratio, and get about 2/3 of the effect.  Swingarm length actually has the opposite effect though.  The longer you go, the more squat you will get.  It has to do with the instantanous force line created by the contact patch.  Moving the contact patch further back results in a lower AS angle.

 

I guess what it comes down to is this....I am going to try it.  I do not want to mess with the sag or shock, as I have the cornering feel the way I want.  I just want the bike to squat more coming out of corners... 

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Have you tried going in on the high speed? Try HSC at 1 on the rear shock

 

Forget what I said, I completely misunderstood your question. Have you tired the HSC at 3 out haha

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I guess what it comes down to is this....I am going to try it.  I do not want to mess with the sag or shock, as I have the cornering feel the way I want.  I just want the bike to squat more coming out of corners...

Thanks for the info on the chain effects. Let us know how you go.

With chassis or suspension setup, every time I've wanted to leave something alone and solve an issue another way, I've had to (eventually) change that thing I wanted to leave alone and start the tuning process again. So it's been a cycle.

I'm guessing that you can keep your cornering behaviour and get more squat if you left the sprockets as is, and went for a solution with a different effective spring progression and find the required damping.

Time of course is a real constraint.

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I have gone back in fourth with links.....there must be a point where you can even it out though right? Wheel rearward with a slightly softer spring and a more progressive link to drop it down.......or standard link and firmer spring......I was under the impression that you can change the bike in motion. With the two scenarios above I have had the same sag numbers but the bike feels better in terms of squat with the link.

With the chain link on the RMZ it's amazing the difference in feel with wheel position...

Edited by mikerides33

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Riding technique plays a huge part here, there is us 2 stroke guys that rev the snot like barcia but never load up the swing arm and then there is the lug the motor like roczen and load up the chassis style

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The link made the difference for me. Even with an improper shock set up. It gave the exact feel you seek. Then I finally got the set up on the my shock correct and it was night and day better. I finally have the set up that does everything. Idk if there is a stock set up out there that could perform any better for me. 

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I will let you know how it goes.

 

In case anyone is interested in reading about this sort of chassis geometry stuff...check out Paul Thede's 'Motorcycle Suspension Bible'...

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Yes that book has a lot of good stuff. But it's amazing it's out of date already, since it would be cool if it covered some of the air fork servicing.

The extent of squat is related to spring rate. The rate of squat is related to damping.

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No trying to beat you up, but I believe someone asked this earlier, I did not see your response. Have you checked your SAG? When I purchased my 2013 it was not adjusted properly and squatted bad. I adjusted it and problem solved. No squat and wheel comes up on demand.

 

Mark

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12/46 really worked.  Do not under-estimate how much of a difference this can make.  Much easier to keep the front light.  In addition, when I am at the limit of grip and I start to lose the front, it gives me a TON of warning.  The front goes light, overturns a bit, but I can save it and stand the bike up before hitting the dirt...especially when standing.

Edited by Blutarsky

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