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I and requesting some help in the most general form.

I have a cfr230 with modified suspension that consist of a raised rear by means of a crf150 rocker.

and I have late 80's CR500 conventional forks and tree mounted up front.

im a bulky 250 lbs and ride technical single track scrambles.

 

I have a noticeable amount of what I call front end push that I would like to reduce.

So im just looking at the variables and wondering what the best sequence to address the push.

 

Remove preload spacer in forks.

increase or decrease rake angle.

increase or decrease rear shock preload.

learn how to ride 🙂

 

last race my front tire was low so I bummed some air and got it a little excessive (16 LBS)

I normally run 14 lbs in the front

the push increased dramatically and the bike acted like a ping pong ball in a dryer in the creek beds.

 

I have checked and set sag but due to the suspension mods im not sure that my sag setting are the real target.

 

 

 

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I'll go out on a limb and bet that your new forks are WAY longer than your stock ones and even with the rear ride height raised, the front is still much too tall and you gained a ton of rake/trail. The axle offset may be different as well. I've played the same game when swapping front ends on many trail bikes over the years and have learned to take baseline rake/trail measurements BEFORE swapping parts. If you can afford to slide the fork legs up in the triple clamps (without the tire bottoming in the fender) try that out and see if the condition improves.

 

Go to Harbor Freight/ Lowes/ Home Depot and buy a cheap angle finder and see what your current rake is (just stick it on your fork tube or head tube.) Next, pull a string line down the center of your head tube (as viewed from the side) all the way to the ground and at the same time drop a plumb bob from the center line of your axle to the ground, the difference between these two points (at the ground) is your trail. Compare that with the factory specs for your bike, and I bet you'll find the reason for your handling issues.

 

Honda specs your bike at 27.3* rake and 112mm of trail. Let us know what numbers you come up with.

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... You also need to tell us what your sag is at (both front and rear) but at 250lbs, I can pretty much guarantee that you either have way too much sag and/or way to much preload on the rear spring trying to compensate for being too soft. Too much rear sag will cause similar issues as too much rake/trail. Looks like the stock rear spring is a 9.0, I haven't seen too much in the way of aftermarket support for the rear shock being that it is a "non rebuildable" unit, but BBR does sell a 12.5 rear spring for your bike. You will likely need more rebound to compensate for a stiffer spring and the only shop that I have seen messing with the "sealed" shocks is Hlebo in San Jose.

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