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Suspension Spring Rates

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I'm about to order these springs for my 03 DR 650, front .47 kg/mm, rear 8.3 kg/mm. I'm about 180 lbs. geared up and usually carry about 70 lbs. including the panniers when I tour. Also I have the IMS tank. Could I get your opinions on whether these rates are correct?

Thanks

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While your spring rates may well need to be bumped up IMO the poor damping of the standard components are a big part of the equation and if not addressed stiffer springs will further overpower the weak rebound.

There are inexpensive ways to do this, via fluid change, which are helpful and much more costly (and effective) options. I would have a look at what Pro Cycle offers.

Bruce

Edited by BDM

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I am about 10 lbs heavier that you. Dampening was more important than springs in the front for me. In fact the heavier springs had a negative effect on the road (magnified road irregularities through the handle bars at 40 - 50mph). I put the stock springs back into the forks this time with .750 preload plus the emulators. I kept the heavier rear spring but i don't run too much preload. The sag is set at 1/4 of the total range in the front for me and 1/3 in the back.

The goal valve in the shock made a big difference. :bonk:

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The rates you suggest will work for you.

I use a 0.47 front and an 8.0 rear and am about the same weight and carry the same load as you.

For me this works well and an 8.3 rear will be about the same.

Do not believe the race tech calculator as suggested above it will be way too heavy.

If you want other advice contact Procycle US.

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I rebuilt both the front and rear suspension on my DR650. Up front I went with .47kg/mm Eibach springs and Race Tech Emulators. Huge improvement over stock, but actually a little on the stiff side, even with me being 290 lbs at the time. Out back I used an 8.3 kg/mm spring and Race Tech Gold Valve kit. Once again, huge improvement. With the 8.3 spring, I found it was a little too stiff, and tends to get a bit of "pogo" effect in rough, rocky sections. I am going to swap it out for a 7.4 (now that I am down to almost 230 lbs :bonk: ), and am looking at the shock shaft from Pro Cycle with the rebound adjustment as well. I ride 95% off-road on rough jeep roads and single track. I am suprised on how well "Large Marge" handles in this terrain. I can't keep up with the lighter, more off-road oriented bikes, but have suprised many with where I can take it.

I just recently bought a complete front end off of a 2001 RM 250 - USD Forks, triples, caliper and front wheel. It cost me $300.00 for everything, and is a direct bolt in. The forks just got back from having an RG3 rebuild and revalve, with new .48 kg/mm springs. That wasn't cheap! :lol: I have six weeks on crutches with a cast on my foot, and then I can get everything buttoned-up and see how she rides!

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I'm about to order these springs for my 03 DR 650, front .47 kg/mm, rear 8.3 kg/mm. I'm about 180 lbs. geared up and usually carry about 70 lbs. including the panniers when I tour. Also I have the IMS tank. Could I get your opinions on whether these rates are correct?

Thanks

These are good rates. But as mentioned, the shock will need more help to really work well. I have .47 kg/ fork springs and at some point may go with Race Tech emulators. Out back I started with the stock shock using a 7.6 kg/mm Eibach spring. I weigh about 200 lbs. and carry about 70 lbs. at max. On weekend or day rides, much less. I needed a heavier spring but the real problem is lack of rebound damping and poor performance of the stock unit. A heavier spring just makes this more obvious.

I found an old Ohlins that fits the DR (they no longer make one for it). It's fantastic.

Various companies make shocks for the DR650 or you can go with Cogent Dynamics, who rebuild your stock item for about $700 (includes spring) Reports are very good.

You can do LOTS of fine tuning with the front forks by varying the pre-load, oil weight and oil level. If you're patient you can really get it nice doing this. You can also have the front end re-valved but an expert or do it yourself. Emulators are nice too.

With a big load on the DR650 off road you may need a fork brace to help settle the front. Really helps in rocks, ruts and sand.

So springs are a good start ... but much more to be done.

Edited by 54321

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