Heim joints are the best way to go. They are darn near bullet proof. They are what all of the off road rock crawlers use. I have used them for years with no troubles. Try them, you will love them.

 

Hey bombduner, where can we get some of those at...

 

my terminology is a bit off from the parts fiche, or vise versa [img]i/expressions/face-icon-small-confused.gif[/img]
but what I was refering to as bushing is the black plastic pieces the steel "sleeve" pivots in, there are two per pivot

if I undersand correctly, and its possible I may be wrong, but I think that the gemoetry of the new a-arms isn't different from the old, they are just maufactured different, when they came out Bomb also switched to Ohtsu Radials the same time and also changed the rim offset - and when they came out two different magazines did a test by swapping wheel/tire combos from an old model to a new model, and all handling characteristics migrated as well. however the new models still cannot run the same toe-in as all the other Jap bikes out there, toe adjustment is being used to help tame what would otherwise be less than ideal handling.

going to an adjustable a-arm gives you the ability to increase the caster angle to the point of being able to run more toe-in. more toe-in means tighter turning radius, better response, and less bump steer - where bump steer is defined as the big jerk your bars give to your hands when you hook a tree or rock with the outside of your front tire on the trails. running ideal toe-in with the factory DS caster angle of a mesely 5 degrees makes the steerign much too sensetive. just changing the caster to 7 or 8 degrees makes enough difference that you can increase toe-in quite a bit without making you trip ***** at high speed in the loose stuff, and really helps on bump steer to boot.

swapping to aftermarket a-arms its just a suggestion for this post, no it is not totally necesary, in fact I never was too unsatisfied with my stock a-arms, but after swapping the improvements are greater than I anticipated before doing it.


As far as Heim durability, ASR is using inexpensive heims on their $165 upper a-arm kit - that is why it is so cheap compared to others out there. But JMann I ride the same kind of stuff you do and my pivot heims are still rock solid after almost 3 years, however the ball joint heims that the steering knuckles mounts to developed quite a bit play in that time and I just swapped them to the ultimate in durability heim that has teflon/kevlar lining. Time will tell on these, but regardless even if I have to replace the ball joint heims very two years I am still happy enough with the added performance that its worth it. FYI The cheapy ball joint heims are like $12, the high end ones are around $30.

Aso FYI, my stock lower ball joints, now over 6 years old, have a fair amount of play now - nothing lasts forever. And they are pricy. But I have the joints on my upper a-arms I removed to install in their place now.


Bioware you haveto have a-arms designed to use heims, you cannot install heims on stock a-arms.

 

Hightower is right on with the suspension stuff. It was proved to me when one season I started lowering the rear of my bike (for what reason, I couldn't tell ya, I just was messing around). I ended up getting it borderline too low, and to make a long story short. The steering felt great. I actually didn;t want to raise it back up, but I was waisting like half of my rear suspension. The basic idea is the same as the ASR's or any other adjustable a-arms. The steering was smooth, and there was alomst no bump. It sold me on the ASR's.

 

Thanks Hightower for the info. Looks like I will have to invest in some new A-arms this fall. what brand do you recommend, that is cheap but good quality.. Your info was very good, I wish everyone could explain things more clearly for us not so good mech....

Thanks
Bryan

 

Hey Hightower, thanks for taking the time to type that up. It makes sense and I will probably make the switch once I get my stem and clutch actuator fixed... my buddy ben took a little tumble on my DS at Little Sahara.

 

Oh, question for ya...How do you measure for your caster adjustments?

 

American Star Racing (ASR) is the only maker I am aware of offering uppers only with complete adjustability - they are $165 all day long on Ebay.
Other than them, you are looking at minimum of 5 bills for a complete set uppers and lowers from the other guys.

Keep in mind, the Armadillos are not adjustable in caster, but I do not know what the caster angle is that they make them. There is another company, called Strong-Arm, who makes a-arms for the DS - they are not adjustable in caster either, but the maker builds them with 8 degrees caster which is what I feel is ideal. It is possible that Armadillo is correcting caster too, but I do not know.


To set up caster and camber you will need an ANGLE FINDER
Purchase this simple and cheap $6 tool and you will not be sorry.

The bike MUST be perfectly level side to side, but also postioned with the bottom frame running front to rear sitting at whatever angle it would normally be sitting at if the bike were on all 4 tires. So BEFORE you tear it apart and install the new arms, stick the angle finder under the frame rail and measure the angle it sits at with you on the seat. Then when you raise the bike with a lift or whatever you come up with, be sure it is positioned at this same angle front to rear, block it up as necesary. And perfectly level side to side.

Now do your swap. Be certain that when the suspension is fully dropped (extended) that the bottom edge of the tube that the ball joint screws into does not hit the shock body - or else it will dent when riding. You simply screw the a-arm pivot heims out far enough to prevent this. If it hits the shock, they need screwed out some more. But don't screw them out any further than they have to be for clearance. Start out with both pivots on both sides screwed out equally before procedding to the below.

Now set up caster - postion the bars/steering EXACTLY centered. This is tricky, you can come up with a million ways to try and verify it and eveyr one will have a loophole, so just do your best. place a straight edge against the front of the knuckle, so that it cuts straight thru the center of the holes that the upper and lower ball joint stems are in. Stick the angle finder against the straight edge. The measurement is caster. Bear in mind - the bottom joint must be farther forward towards the front of the bike than the top. So the top joint is farther back towards the rear than the bottom. This is positive caster. If you are swapped vise versa and set it up with negative caster, you will **** your britches first ride. You adjust the caster by screwing the pivots in or out, either the front one or the rear - take your pick. After setting caster, be sure to double check shock clearance - you don't want any dents first ride out.

Now set camber - to measure camber you simply stick the sangle finder against the brake rotor. Be sure it is straight up and down using a small level against the side of it. The top of the rotor should be closer to bike than the bottom, so that the bottom of the rotor is farther away from the bike. This is positive camber. I am set up at 2 degrees, pretty much same as stock. Different strokes for different folks - more camber helps fight tire roll in corners but also contributes to uneven wear. Put it where you like it. Adjust by screwing ball joint in or out.

Use the angle finder to set up both sides of the bike - do not assume you can just counts the number of threads showing on everything after setting up one side and then set the other side up that way!

 

That is some great info Hightower. thanks again. I made a copy for my records for later use..

Bryan

 

Lonestar racing just released a set of a arms for the DS along with a steering stem and some other stuff. I believe the upper a arms are the heim adjustable ones. They have always made very high quality parts and I will probably order a set.