The 'No Pissin and Moanin' DR650 Thread

[ungeheuer]

Originally Posted by el capitan

Hi ungeheuer, those on ebay are exactly what I use - 30 mm plus for the rear, improves handling a lot in my view. Whatever other people say, they definitely work.

Thanks for your input el capitan.

When I look at the rear suspension linkage on my DR it looks pretty much like the one pictured below....



... and I cant see how its possible to fit shorter length dogbones since the rear of the linkage arm is almost touching the swing arm already??

But your experience is that these things do fit and work well, so I'm clearly missing something here..................

I hope you dont think I'm trying to contradict you, I'm just caught between what looks like it wont work and the fact that you're up and running with 'em.

[ungeheuer]

... think maybe I've figured it out...



There IS room, because A, B and C are not all fixed points.

A - C is a fixed distance.
C - B is a fixed distance.
A - B is a variable distance.

So... if the (fixed) distance between A and C is lessened (by fitting shorter dogbones) then the effect has got to be that B is forced to rise (compressing the shocker) whilst A lowers (raising the rear end of the bike).

Meaning that a taller ride height is achieved at the expense of reduced suspension travel.

[el capitan]

Originally Posted by ungeheuer

... think maybe I've figured it out...
Meaning that a taller ride height is achieved at the expense of reduced suspension travel.

ahhh ... NOT. You keep all your suspension travel, but the shorter dogbones send your leverage earlier into the progressive range, resulting in a shock that stiffens progressively (and earlier in the travel than with the longer stock dogbones), the more you compress it. In fact you might USE less of your travel for this reason, but it is still there.

During winter I plan to dismantle the entire bike to have the frame powdercoated and use the time to rework my rear shock once more. Currently I ride a stiffer spring, 10w fork oil inside AND shorter dogbones. It is really good on the road (@180lbs naked rider weight), but could be more comfy. This year I tried the stock dogbones, but instantly disliked the handling - the shorter dogbones give you a steeper angle for your fork, resulting in a very quick handling without sacrificing highspeed-stability (= the way I like my bikes). So this winter I´ll give the stock spring, 7,5w fork oil in the shock and the shorter dogbones a chance. Handling should be the same, while I´d be able to use more of the travel and regain my adjustability of compression damping (now fully open).

I made the same observation with my SV 650 K4, that I equipped with a GSX-R shock AND shorter dogbones. The Gixxer stock spring was already a bit much for the SV and the shorter dogbones had the same effect now observed with my DR: good on the racetrack, but barely rideable on bumpy roads. I would´ve needed a softer spring but had been too cheap back then ...

[Adv Grifter]

Great comments ... all the best with your Winter project.

There are a couple other ways to achieve what you seem to be after. When you rebuild your shock you could work with the shim stack and oil flow to add a more "plush" feel.

Also, if you're shock is over sprung (??) then perhaps a slightly lighter spring could help? Adjust pre load firmer if needed.

Quicker steering can also be achieved by lowering front end (raising fork tubes UP in triple clamps).

I'm lucky to have an Ohlins shock on my DR. It has adjustable Ride Height, which is nice to fine tune geometry and balance front to rear.
But I worked a long time on my forks to get them Plush, yet still good at high speed on tarmac. I've got a decent compromise now. Race Tech emulators, 10 wt. oil, heavier springs ... and lots of playing with pre load.

Is your bike a Super Moto conversion? I would imagine YES ? ... since you've got to go a long way in Austria to do any significant off road riding.

Maybe a vacation to Morocco?

[ungeheuer]

Originally Posted by el capitan

ahhh ... NOT. You keep all your suspension travel, but the shorter dogbones send your leverage earlier into the progressive range...

I really would like to accept what you're saying here, but I'm not convinced....

But again thanks for sharing your thoughts on this.

[el capitan]

@ ungeheuer: Your shock´s travel x ratio of linkage = rear wheel travel. You alter the linkage-leverage, not the shock´s travel or rear wheel travel.

@ grifter: I raised the bike by purpose: I´ve got an inseam of +36" and also made my seat higher to fit my ergonomics. Revalving my shock would be the best option, yes. But I am NO suspension professionalist and don´t even know where in the shock the rebound stack is. By playing with oil I just try to find a compromise that provides noticeable rebound, while not being too harsh on the compression-side. My rebound now is perfect for the street and a bit too much for offroad, so going down from 10w oil should be ok.
The bike has stock wheels - I don´t like the feeling of riding with "no" front wheel I always experience when riding supermotos.

[Bronco638]

Originally Posted by JagLite

First step is to measure the static sag, the difference between the length of the forks with the wheel off the ground, and with the bike weight (no rider). Then measure the "race" sag with you sitting on it. That will give you an indication of the spring rate. By giving us the free sag, race sag, and your weight. We can guestimate the spring rate for you by what we have. Make sense?

OK, I measured the length of the forks with the front wheel off of the ground: 35.125" (35 1/8").

The length of the forks with the front wheel on the ground: 33.4375" (33 7/16")

Static Sag = 1.6875" (1 11/16")

The length of the forks with the front wheel on the ground and me sitting on the seat: 32.625" (32 5/8")

Race Sag = 2.5" (2 1/2")

My weight = ~180-185 lbs. with riding gear

So, can anyone tell me what they think my fork spring rates might be? And/or if the forks are sprung appropriately for my riding weight?

TIA - Dave.

[Adv Grifter]

hey Dave,
Sounds like you're at least in the ball park. How does she ride? Ultimately ... that is the real test. Suspension feel is subjective.
Many complain of excessive fork dive with stock progressive fork springs under HARD braking. But go to far the other way ... and it can become harsh, unrideable.

Ideally your bike will ride with the forks using mostly the UPPER 30% of the travel. If it's riding way down the travel (like 50% down) then that is not ideal. Better rebound valves (EG: Race Tech Emulators) heavier springs and slightly heavier oil can improve feel the get you riding UP in the travel. This should offer more plushness, take big hits better and give better feedback.

When you install the Race Tech kit you drill out the damper rods. This allows more oil to flow ... really seems to help over all performance.
(sounds hard, but is very easy to do)

Pre load is also important and easily variable. Just remember ... every change you do ... affects ever other element in the mix. (oil weight, oil level, spring rate, RT damper adjustments, pre load adjustment)

Have fun!

[macrae85]

Originally Posted by acesandeights

What's the best sub-$1k suspension upgrades to the DR650? I have a Baja trip planned and it looks like I can get Racetech emulators, springs, seals, oil, etc for the front and a shock shaft assembly and spring for the rear for ~$850 ? I thought about a front fork swap, but I'd still have to have it sprung for my weight.

Get onto eBay.de (Germany) and get yourself a Wilbers shock......well engineered!

[Adv Grifter]

Originally Posted by macrae85

Get onto eBay.de (Germany) and get yourself a Wilbers shock......well engineered!

Ah Hmmm ... or .. Call the USA distributor in Los Gatos, CA and have them build a Wilbur's up custom for you. Should be at your door in under a week. Super helpful guy there, knows his stuff. Good product.

[kbuckey]

Originally Posted by Adv Grifter

Ah Hmmm ... or .. Call the USA distributor in Los Gatos, CA and have them build a Wilbur's up custom for you. Should be at your door in under a week. Super helpful guy there, knows his stuff. Good product.

I love the Wilburs shock. After I messed with the fork and got it pretty much where I wanted it, that made the rear shock's problems much more noticeable. The Wilburs and stiffer spring made all the difference. It rides like I want it to now

[Bronco638]

Originally Posted by Adv Grifter

hey Dave,
Sounds like you're at least in the ball park. How does she ride? Ultimately ... that is the real test. Suspension feel is subjective.
Many complain of excessive fork dive with stock progressive fork springs under HARD braking. But go to far the other way ... and it can become harsh, unrideable.

Ideally your bike will ride with the forks using mostly the UPPER 30% of the travel. If it's riding way down the travel (like 50% down) then that is not ideal. Better rebound valves (EG: Race Tech Emulators) heavier springs and slightly heavier oil can improve feel the get you riding UP in the travel. This should offer more plushness, take big hits better and give better feedback.

When you install the Race Tech kit you drill out the damper rods. This allows more oil to flow ... really seems to help over all performance.
(sounds hard, but is very easy to do)

Pre load is also important and easily variable. Just remember ... every change you do ... affects ever other element in the mix. (oil weight, oil level, spring rate, RT damper adjustments, pre load adjustment)

Have fun!

I'll be honest, it feels OK but I know nothing of what it "should" feel like. What initially caused the concern was the fact that I rode over a curb, on purpose, at slow speed and promptly compressed the forks so much that the fork brace impacted the o.e. fender. I had one of these on the forks:



I have since purchased a Superbrace but have not yet installed it. The p.o. told me that the owner, previous to him, had done work on the forks. But, he did not know what was done. I have the stock fork boots on and they seem slightly compressed (they seem slightly twisted but are not).

Since there is no markings on the fork springs in my spares pile, I'm not sure if they're o.e. or something else. I do seem to have the o.e. spacers in the spares pile so I'm curious as to what's in the forks.

Ultimately, I would like to lower the DR using the lowering procedure in the shop manual. The owner that did the fork work simply lowered the forks 3/4" in the triples and moved the lower shock bolt to the upper hole. I believe this also makes the steering quicker. I have since determined, by measuring, that the fork internals are not in the "lowered" orientation. So, I moved the forks lower in the triples (so the cap is just above the upper triple clamp) and moved the lower shock bolt to the lower hole. I don't mind having to be on tip-toes when stopped but when fully loaded, I prefer to have both feet firmly on the ground.

My preferred riding is dirt/gravel roads, two track, Forest Service roads and the like. I don't ride much single track and certainly nothing with an MX feel. So, the suspension doesn't need to be super-aggressive but, after the curb/fork brace impact, I'm wondering if it's too softly sprung.

I guess I'm just going to have to take them apart and find out.

[macrae85]

Originally Posted by Adv Grifter

Ah Hmmm ... or .. Call the USA distributor in Los Gatos, CA and have them build a Wilbur's up custom for you. Should be at your door in under a week. Super helpful guy there, knows his stuff. Good product.

The whole World doesn't live in the USA......Fox News may make you think that way,but sorry,it's not the case! :p

[acesandeights]

I think he was saying that because I was the one asking about suspension and I live in the US.

[Adv Grifter]

Originally Posted by Bronco638

I'll be honest, it feels OK but I know nothing of what it "should" feel like. What initially caused the concern was the fact that I rode over a curb, on purpose, at slow speed and promptly compressed the forks so much that the fork brace impacted the o.e. fender.

Bottoming under that circumstance is pretty normal. It's what SHOULD happen with a severe hit.

Originally Posted by Bronco638

I have since purchased a Superbrace but have not yet installed it. The p.o. told me that the owner, previous to him, had done work on the forks. But, he did not know what was done. I have the stock fork boots on and they seem slightly compressed (they seem slightly twisted but are not).

loosen the little screws holding the boots ... adjust as needed. While doing that ... pull them UP off the fork seal and clean in there ... and check for leaks.

Originally Posted by Bronco638

I guess I'm just going to have to take them apart and find out.

Yep! That's the thing to do. Then try different settings and see what works best. Try not to tie yourself in knots with this and end up chasing your tail. Keep track of changes made. Use the same test loop to check out performance and note changes/impressions.

After a while you should learn what changes affect riding manners ... do incremental changes. Yes ... it takes time to get it right.
Good luck.