Swing Arm Cracks at 6800 KM

[Kinarfi]

Pictures are worth a thousand words each

[ricksrb]

Pictures are worth a thousand words each

is that 12 photos of one joint with a cracked weld or multiple joints with cracks??

[Kinarfi]

at least 4 cracks, going to pull the swing arms and start welding them solid and put a plate across the bottom like Lenny did. I'll get one photo of each swing arm and them doctor the photo to show where each crack is, they are on both swing arms.

Jeff

[Kinarfi]

Added some more pictures 2 of 8

Sorry for my original title, I was frustrated and tired of working on this thing, I WANT TO GO PLAY WITH IT!!!!!!!!! NOT WORK ON IT!!!!!!!! Oops sorry again for screaming.

Any way, I suggest you all take a gander at your swing arm welds, I don't think I was that hard on my trooper and I know some of you are a lot harder on yours.

I have welded the cracks shut and put some extra metal where the cracks were and I have made a template for boxing in that last side and will get some 1/8" steel to weld to it on Monday. That should toughen it up some.

Jeff

[Guest Lenny]

Added some more pictures 2 of 8

Sorry for my original title, I was frustrated and tired of working on this thing, I WANT TO GO PLAY WITH IT!!!!!!!!! NOT WORK ON IT!!!!!!!! Oops sorry again for screaming.

Any way, I suggest you all take a gander at your swing arm welds, I don't think I was that hard on my trooper and I know some of you are a lot harder on yours.

I have welded the cracks shut and put some extra metal where the cracks were and I have made a template for boxing in that last side and will get some 1/8" steel to weld to it on Monday. That should toughen it up some.

Jeff

The plate for the bottom only needs to be 16 gauge but the reinforcement strips for the pivot points should be 1/8". Don't add the extra weight by going to 1/8" on the bottom. Do run the bottom plate all the way to the very end. Don't forget to add the pivot point grease fittings while they are off. The design of the stock swing arms is wrong and so is the improved design that Joyner did. All they did was to try and reinforce the bad design instead of correcting it. Being under torsion, it needs to be completely boxed to prevent it from twisting.

Lenny

[2scoops]

Eventually I will be looking into redesigning the swingarm completely, especially since my rt rear swingarm is 1" out of alignment anyway . I think it is poorly executed and can be much more simple and stronger--saving some weight. I like the prospect of the design they used on the RZR XP:

http://sxsnews.com/index.php/vehicle-features/polaris-rzr-900-xp/

[Guest Lenny]

Eventually I will be looking into redesigning the swingarm completely, especially since my rt rear swingarm is 1" out of alignment anyway . I think it is poorly executed and can be much more simple and stronger--saving some weight. I like the prospect of the design they used on the RZR XP:

http://sxsnews.com/index.php/vehicle-features/polaris-rzr-900-xp/

The lower shock mount wants to be mounted as close to the wheel (moved to the outside) as possible to limit the torque it imposes on the swingarm. That alone will make a major differance in the strength of the swingarm. Even though there are other problems with the swingarm, the ones out there that are cracking and twisting are from the twisting moment that the shock applies to the arm.

Lenny

[rocmoc]

Yup, what Lenny says!

[huunz]

Pictures are worth a thousand words each

I also had a cracked arm. I somehow have too many pictures up, so can't show my fix.

[huunz]

I also had a cracked arm. I somehow have too many pictures up, so can't show my fix.

I was able to find the gallery and upload my photos of the cracks.

My link

[Banjo Minnow]

Here is a pic of the broken Trailing Arm.

We had to take it off on the trail and take it to town and get it welded back up. It was fixed and worked fine, but I am planning to make it stronger so it doesn't happen again.

[Guest Lenny]

Here is a pic of the broken Trailing Arm.

We had to take it off on the trail and take it to town and get it welded back up. It was fixed and worked fine, but I am planning to make it stronger so it doesn't happen again.

I have reinforced the pivot sleeves some time ago. Mine too failed after I strengthened the swingarms to better resist the twisting torque put on them. The torque strengthening moved all the stress to the next weak point which is the anchor sleeves. You will want to box your swing arm by adding a plate on the bottom and weld continous weld beads on all. Moving the lower shock mount out closer to the wheel is a big advancement towards elimiinating the twisting torque on the swingarm.

Lenny