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Rear Wheel Hop

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I just got 17's and am running the Maxxis Presa M6119 on the rear. I went out to a empty parking lot to practice and I noticed that when I was backing the bike in the rear tire was hopping. I found that the only way I could get it to slide without hopping was if I was on the front brake really hard. I was wondering if this is normal or if adjustments need to be made to the suspension or if its jsut cause I dont know what I am doing.

The bike is a CRF250X everything is stock except the 17's. The suspension is setup for racing Hare Scrambles. I know I should lower it and get stiffer springs but I use the bike for trail riding/racing so need all the help I can get.

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This is going to sound a little complicated but it's not.

First, Braking hard with the front really hard is the most important part.

Then as you are using the rear brake, slightly slip the clutch so the engine braking has less effect on the rear wheel.

On a lightweight bike, sliding the rear around is not required for getting around a track quickly, it's fun though! :cry:

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Also, sit up a little more forward on the bike as you approach the turn, you may also want to take a couple clicks of compression out of the front so the bike dives a little more and unweights the rear better.

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increase (slower) you're rebound on the rear, and dial more comp and rebound on the fork for starters. You might try more preload on the rear spring as well...

.02

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no offense but the suspension suggestions are already

contradicting (add/reduce comp to forks). forget it

all. give into the dark side and buy a slipper. they

work like magic (well, as long as they don't they fall apart).

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or the no cost option is to simply feather the clutch when the hopping starts.

Cheers,

Simon

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I like the no cost option, I am a broke college student, can barely afford to race much less a slipper. :cry:

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Adding comp and rebound in no way is contradicting...this will slow you're forks in both directions. Coming from a trail/dirt set up, stiffer and slower is probably going to help. I know guys who ride fast with stock suspension turned up to near limits on damping, in both directions. :cry:

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Oh yeah, rear wheel hop is usually associated with rear wheel barely contacting the ground, then chain slop begins to cycle from tight to loose, so yes , clutch method should be altered

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Adding comp and rebound in no way is contradicting...

I was referring to the advice between you and TeamScream.

One says to add compression to the front forks (you) while

the other suggests reducing front fork compression (TeamScream). I am in no way suggesting that either is

right or wrong. It just goes more along the lines of conflicting suspension change suggestions for a single

indication (in this case rear wheel hop).

On a second note I agree with you completely on the reasons for rear wheel hop (low rear wheel weight, chain slop

cycling: wheel off the ground chain becomes loose, wheel touches down and spins until chain tightens, when the chain

snaps taut the wheels hops and the whole process starts over again).

I also agree that it can be controlled with the clutch, but (ignoring financial cost) I believe that when "I" have

tried this I am spending mental dollars focusing on the amount of clutch pull rather than devoting all my attention

to going through the turn as quickly as possible. I will agree that the clutch method is financially much

cheaper. But after spending so much $ on bike, leathers, travel time/costs, entry fees, tires, etc......... What's

a few more bucks, it might even help you get a $2 trophy?

Nova: I really do understand the broke student situation, I was a "professional student" for a long time. The clutch method is probably the correct answer for you.

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Is there and/or will there ever be a slipper clutch available for a CRF250? :cry:

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This thread just go's to show that there will be as many different opinions as there are racers.

I prescribe to the theory that puts more weight on the front end whenever possible with these bikes.

After all, you will chase that (too little weight on the front end) demon right after you get rid of the rear wheel hop, and end up with front end chatter which plagues ALL of these bikes once you get fast enough.

So in short, and in MY opinion you want the front to dive upon initial front braking to unload the rear wheel (makes the tire break loose easier) then you dump the clutch about half way as fast as you can really, then feather it the rest of the way to control hop and the amount the rear end swings out during a slide, the feathering part is pandora's box since once you induce rear brake into the equation the method changes a bit.

The other poster is correct as well (when compared to my method) in that you really want to control rebound BOTH up front as well as in the rear, because after the slide is induced, you dont want EITHER end to unload to fast, but the front end in my opinion is critical, because once you square the turn with the slide, you still have to rail the apex, and the exit at or near full (peg dragging) lean, and that is when the front end chatter will start to rear its ugly head.

So by allowing the front to dive on initial braking, and controlling the rebound up front without sacrificing your performance on jump landings etc. you will also be taking steps in the right direction to keep the front end loaded up, which allows the tires to work, get hot enough and NOT chatter nearly as much.

Finally, there really is a HUGE benefit having a slipper clutch to control hop, and setting the bike up correctly to contain front end chatter while still allowing for good landing and stutter bump suspension performance.

Making the first 2 inches of travel work perfectly seems to be the "golden goose" of supermoto performance setup.

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Well put. Front end chatter is the ultimate demon. Just sent my forks out to raise them back up 10mm (were 40mm lowered) to combat overloading front end (and associated chatter) on off throttle full lean situations. A firmly planted front end definitely is more critical than a well slid rear end (maybe not as fun though :cry:)

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Yeah what they said ^

As long as the rear tire does the same dance on a particular corner entry on every lap, I don't care all that much.

Getting the front-end right is key! High corner speed is criritical on a 250 4-stroke. :cry:

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Went to the track and pracitced slipping the lucthc like you guys said made a huge difference but was still getting some hop, them one of my buddies helped me with my suspension and it worked great. Turned the rebound in front and rear all the way stiff (slow) then backed it out 2 clicks. Seems to have fixed my hop problem.

After my first heat I ended up like completely melting my rain tires so I threw on slicks (first time on slicks) they are awesome, at the end of the main i was still getting traction!

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That's great.

It's good to see that sometimes this internet babble is actually usefull. :cry:

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I took my XR650R out to the West Coast SuperMoto school and had Darrick fiddle with the suspension (BTW: all part of the school and worth $200 right there for only 5 minutes of work!). Anyways before the suspenion tune the XR was absolutely jackhammering at both end on the brakes and I had a hard time holding a line and it was sliding all over the place. He cranked in the rebound on the rear almost all the way and and fair a bit on the compression. On the front he actually lowered the rebound slightly and cranked up the compression. Also, he set up the air pressure to a proper baseline of 24psi on both ends (I was running 32psi).

F-Ing AMAZING!!! Dead stable on the brakes -- and I wasn't even bothering slipping the clutch coming into the turns. Also, made the pig XR feel 50lbs lighter and held a line that I thought was impossible on that bike just an hour before.

Again -- 5 minutes of work on stock suspension from someone who knows what the are doing.

Moral is -- explore the options you have in your suspension before dropping tons of cash on trick bits like a slipper clutch or steering stabilizer. You probably won't be solving the real problem with your expensive trick bit and just wasting money...

-Micah

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