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Please help a DRZ400SM Newbie with some big boy suspension advice

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This is my first post so please excuse me if I'm asking a redundant question. I recently purchased a 2005 DRZ400SM. The bike only had 1,500 miles when I picked it up this past weekend. The owner did some performance mods and essentially parked it. Bike runs good but the suspension is collapsed under my 240lbs. I've done nothing to the front forks and they are not too bad but I will adjust them a bit more this weekend. I did put 3 turns of preload on the rear spring and dialed adjusters all the way in and out to find a baseline setting. I have the rear shock low speed compression set at 9 clicks out from   closed out of a total of 27 clicks. High speed has a total of 4 complete turns I have it set at 2. Rebound is set 14 clicks out of a total of 23. This is still way too soft.

 

My question is can I achieve decent suspension for my weight in the stock configuration? The bike sat for so long that the bottom out bumper has dried out and cracked so I'dd like to remove the shock and replace that piece and possibly add a stiffer rate spring? However, I am trying to avoid a huge expense in suspension mods. A Moto Suspension company quoted me approximately $700 to service and add stiffer rate springs on both ends. I can buy the springs and install myself for a much more reasonable price but will the rear need to be revalved? At any rate, I'm just looking for some DRZ-SM suspension blog, advice, videos or solutions on the cheap.

 

Thanks!

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This is my first post so please excuse me if I'm asking a redundant question. I recently purchased a 2005 DRZ400SM. The bike only had 1,500 miles when I picked it up this past weekend. The owner did some performance mods and essentially parked it. Bike runs good but the suspension is collapsed under my 240lbs. I've done nothing to the front forks and they are not too bad but I will adjust them a bit more this weekend. I did put 3 turns of preload on the rear spring and dialed adjusters all the way in and out to find a baseline setting. I have the rear shock low speed compression set at 9 clicks out from   closed out of a total of 27 clicks. High speed has a total of 4 complete turns I have it set at 2. Rebound is set 14 clicks out of a total of 23. This is still way too soft.
 
My question is can I achieve decent suspension for my weight in the stock configuration? The bike sat for so long that the bottom out bumper has dried out and cracked so I'dd like to remove the shock and replace that piece and possibly add a stiffer rate spring? However, I am trying to avoid a huge expense in suspension mods. A Moto Suspension company quoted me approximately $700 to service and add stiffer rate springs on both ends. I can buy the springs and install myself for a much more reasonable price but will the rear need to be revalved? At any rate, I'm just looking for some DRZ-SM suspension blog, advice, videos or solutions on the cheap.
 
Thanks!

 

 

It's better to re valve and re spring for your weight. You can buy Racetech gold valves and do it yourself. It comes with a good D.I.Y. DVD video. They can be bought either online or you get a good discount as a Thumpertalk member.

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Buy this for your weight. Same spring I bought, I'm same weight. Before the stock spring in the rear sagged super low. Its made for a 150lb rider..Now its nice and perfect. Definatley a cheaper way to get it to sit good on a budget. I set the sag and have been plenty happy without going to a susp shop spending lots of $$$ You can pull the rear shock out sorta easy. Take the seat and muffler off and work its way out the right side of the bike. Tight fit but doable.

 

http://www.amazon.com/Eibach-Shock-Spring-6-1-889-0061-1/dp/B000MQ8GG2

 

I literally got it next day too from these guys.

Edited by Kx250FRiDeR651
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Changing to the right rate springs helps a lot. I'm 250lbs and got the heaviest rate set for front and back from Cannon Racecraft. I'm still running stock valving and experimenting with the clicker settings. I don't race or ride super aggressive, so it's working just fine for me. It solved the crazy fork dive and rear end wallowing in the corners.

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How was your damping effected? Can you do such a drastic spring rate swap without a revalve? If so, I'll order one today. I want to set up the suspension appropriately. But my DRZ "must do mods" are adding up

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I think the damping is ok. I still have it set to stock settings. Again, I'm no racer and may not be very sensitive to the subtleties of suspension setup. I've ridden it that way with supermoto and dirt wheels.

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So, I got my rear shock resprung and serviced (new bushings, seals and oil). I did not pay the extra $160 for the revalve but I probably should have. The bike is riding much higher without a lot of sag but damping isn't great. However, I think I can tune in a little more movement but a revalve was probably the way to go. Even though the shock is a bit too stiff, it still handles way better than it did with the stock spring. 

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If you change springs on the front, it can only help. Revalving from there is a question of how much you want to spend to get it right.

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I weigh 250 pounds, I installed the following Race Tech springs and had the suspension shop do gold valves and lower the front 1.5" and the rear .25"  

IMG_1375.JPG

 

Here is a before and after lowering pic. the thing is rock solid on the racetrack all the way to the edge of the front, not a bit of chatter, weight transfer is quite nice, ride is actually plush on the street, not sure where exactly all my adjusters are,as I am at work.

 

Before lowering (with the same springs)

 

IMG_0295.JPG

 

After lowering

 

20150615_082651.jpg

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