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DR650 Motard font end wobble

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I recently motaded my 02 DR650 with 17 inch Excel wheels and heavy duty Buchanan spokes by East Coast Wheels. I have Pirelli Diablos mounted, 120/60 and 160/60. My suspension is stock, forks are in the original position in the triple clamps. Upon entering a corner I get a front end wobble. Under braking the wobble is more pronounced, and increases with entry speed and brake pressure.

Have any of you motard guys had this problem and if so, what was the solution? Firmer fork springs?

Also what final gearing have you found works best on the 650? Stock gearing seems to be too high for me.

Thanks

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I had something similar to that with mine. It was more like a flexing than a wobble. I had planned on a fork brace to fix it, but when I installed the stiffer springs and heavier oil the problem went away. It feels solid now.

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Is your rear suspension set high or low? You lowered your front wheel by 2 inches, and this has radically changed your stearing head angle and trail, especially under braking. If your rear suspension is in the upper setting, it may be too steep. I tried my DR650 with the stock wheels, but the rear high and the front low. It was not stable set up like that.

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What make are the stiffer fork springs for the 650 and what weight and height oil do you run with them? You are correct in describing the wobble as more of a flexing; sounds like the same thing I have going on with mine.

I have my rear shock still in the stock position. Have any of you other motard guys lowered the rear by installing the lower shock bolt in the upper hole, shortening the shock length?

Thanks

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I have the Racetech 5.0 springs with tuner springs 15 wt.oil. For supermoto use, I went heavier on the springs than they suggest for my weight. Mine is lowered in the rear also.

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You "quickened up" your steering immensely by lowering the front end with the 17" rims. The good news is that the answer is right under you. Lowering the rear needs to be done too. Suzuki to the rescue! You have alternatives; either the factory way, or the pick the lower bolt hole way ( easier, economical, effective, my choice ) this will bring the geometry a great deal closer to manageable. It will slow the front end down by increasing the trail ( distance of tire contact patch to the 'imaginary' extended line of the steering head. the greater that value, the less responsive the steering. Think chopper. think Razor scooter. )

Mine was twitchy as a Chihuahua. Not good. First off, your bike needs to be sprung properly; Race Tech or Traxxion Dynamics are the ways to go. It was Race Tech for me. Give them the data and a credit card. They'll do it forks for you, or wrench them your self. Get your sag set ( another story ); then get your geometry correct; sliding the forks in the clamps ( higher to slow the steering response...)

Lower the rear to start, so you can at least ride it. Then attack the problem on all fronts.

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I have the same tire sizes as you do. I have not changed the rear height and while it definately quickens up the steering it is still very ridable with no twitchy problems. With the stock wheels I had high speed twitchy problems that I solved with a fork brace which is still on it with the 17" wheels, perhaps this is helping minimize the problems that you describe. I have a

"short" sidestand on order so I can lower it in the rear to see if I like it better that way. On the gearing question, the 60 series rear tire is considerably smaller in circumference than the stock tire so you are already geared down from stock but try the 14 tooth counter for even more of the Holigan feel.

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I have the same tire sizes as you do. I have not changed the rear height and while it definately quickens up the steering it is still very ridable with no twitchy problems. With the stock wheels I had high speed twitchy problems that I solved with a fork brace which is still on it with the 17" wheels, perhaps this is helping minimize the problems that you describe. I have a

"short" sidestand on order so I can lower it in the rear to see if I like it better that way. On the gearing question, the 60 series rear tire is considerably smaller in circumference than the stock tire so you are already geared down from stock but try the 14 tooth counter for even more of the Holigan feel.

www.thumpertalk.com/forum/showthread.php?t=448833

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After the 120/60 front is done, move on to a 120/70. The bike will be a lot more stable. There is no suspension tweaking necessary to make the bike stable.

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After the 120/60 front is done, move on to a 120/70. The bike will be a lot more stable. There is no suspension tweaking necessary to make the bike stable.

I actually have a 120/70 coming which I will fit and see what it is like. You have stock springs etc on both ends with a 120/70 and your bike is stable in corners?

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remove the corners, add a bunch of cars and that looks like my morning commute.:applause:

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remove the corners, add a bunch of cars and that looks like my morning commute.:applause:

LOL! I know the feeling... I'm looking out my hotel room right now and its pouring rain. Hopefully by 6am it will die down a bit. Back to wading through rivers in TJ. :applause:

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I lowered my rear suspension by using the upper hole in the rear shock clevis and added .9 inches of preload to my front fork springs and now the bike handles like a totally different bike. Still a small bit of headshake in a hard corner under braking but very rideable and quite a hoot to ride. Thanks for the input.

I am going to pursue the Racetech fork springs and 15 wt oil and see if that improves it further. Is the DR650 spring the FRSP3750 46, 36.7 X 505? What kg/mm are you guys using?

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I have the 120/70/17. I have not changed the rear height and while it definately quickens up the steering it is still very ridable with no twitchy problems. With the stock wheels I had high speed twitchy problems that I solved with a fork brace which is still on it with the 17" wheels, perhaps this is helping minimize the problems that you describe. I have a "short" sidestand on order so I can lower it in the rear to see if I like it better that way.

I got the short sidestand, lowered the rear and it is a big improvement in the confidence you feel, definately brings back the dirt bike feel and feels better in the dirt also (duh). Of course the short sidestand is too long now.:applause:

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I run .5 Lowe springs, Race tech emulators, and 10wt. I also use WER steering damper. The front end is way solid with this setup for my weight and riding style. I also run a Wilbers 742 rear shock so I can dial in the rear to match the front. 17's front and back. Ed

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I lowered the back end and fitted stiffer front springs (mainly for my barge arse) and with 16/39 gearing it runs off the speedo easily and is very stable,120/70/17 on the front and 160/60/17 under its big bum.I found with the rear on the high setting it steered like a double decker bus with flat tyres.

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I lowered the back end and fitted stiffer front springs (mainly for my barge arse) and with 16/39 gearing it runs off the speedo easily and is very stable,120/70/17 on the front and 160/60/17 under its big bum.I found with the rear on the high setting it steered like a double decker bus with flat tyres.

With exactly the same tire sizes that you have, I ran with my GPS last week. The error is 20% that is 60MPH indicated is 50 on the GPS. Saw 99.8 on the gps 120 on the speedo. Stock sprocket ratios (15) but the smaller (circumference) rear tire is equal to a tooth down on the CS sprocket.

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Hey Cracker what whels do you run ? I use GSX250F mags with the speedo drive off that bike which ties in perfectly with the DR speedo.I have tested it against the speedo in my wifes new car and a courtesy radar set up by the roads authority and it was within 1 - 2 km/h of the bikes dial.That and the two speed cameras I pass every morning havent nailed me yet,touch wood.

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