AkRacing Garage Polaris IQ Chassis Reinforcements AkRacing
As more and more Polaris Race sleds are converted to ride the trails owners are taking a close look at their chassis and noticing small cracks in the bulkhead. The most noticeable place for these cracks are in the area of the lower A-Arm mounting tabs and brackets, and where the bulkhead is riveted to the tunnel. Race sleds take a serious beating and many race teams do all they can to keep their sleds in top shape for the track. Those same forces that damage a race sled can also do damage when your sled is ridden hard on the trail.
With the price of new race and trail sleds continuing to increase some riders will decide to put some money into their existing sled and get another season of riding out of it. Depending on the condition of your tub plastic you may want to remove it to get access to all the areas of the bulkhead for inspection. Here I will describe a few areas in the bulkhead to look at and consider making structural upgrades so your IQ will last for thousands of trouble free miles.
If you decide to remove the plastic tub pieces and want to reuse them Do Not allow the rivet head to spin while you are drilling it out. This will immediately melt the plastic and cause grief. If a rivet spins, use a screwdriver under the head and pry up putting pressure on the head, this will stop it from spinning. If you can get to the back side of the rivet you can hold it with pliers. Removing all the plastic is a very easy task and we won't be discussing it any further here. At least some of the plastic must be removed for these modifications to work properly.
Rivets are used to throughout the IQ chassis to hold dissimilar metals together and to hold the major aluminum pieces together like the bulkhead and tunnel. Properly installed, rivets are structurally more sound than welds because the the rivets are not prone to cracking. Rivets do come loose over time and any loose rivet should be removed and replaced if possible. Look closely at all the rivets to ensure they are not loose. You can use a plastic screwdriver handle to tap on the rivet listening for the distinctive "tink sound" that a loose rivet will make. Also try to get your fingernail under the rivet and see if it is loose. Use structural rivets from your Polaris Dealer PN # 7661637 or similar. These rivets are far superior to steel rivets available from hardware stores. Consider purchasing or renting a good rivet gun like the "Big Daddy" for installing the structural rivets.
Here are some specific areas to inspect.
Lower A-Arm mounting tabs. Look for and repair any cracks in the bulkhead and the aluminum mounting tabs of the brackets. The rear brackets usually stay pretty secure but a close inspection is necessary. Consider installing the Bracket Support kit available from the Race Department or consider making your own out of .100" steel plate. Here is the link to the Polaris Fix for the rear mounting tabs.
In this picture you can also see how we tied the two front mounting brackets together with a small pie shaped piece of steel. Look closely at all the rivets holding the front mounting tabs together and replace any loose ones.
Here are more pictures of a damaged bulkhead and how I repaired it. Although difficult to see, of the 12 rivets holding the front bracket to the bulkhead 4 of them did not penetrate through the aluminum part of the chassis. If you find more than a few loose rivets in this area you should consider drilling them all out and installing new ones. Depending on the condition and size of the hole left by the loose rivet you should consider going up to the next bigger, 1/4" structural rivet available from Polaris. The 1/4" rivets are sold in different lengths, make sure you get the rivets that are sized to squeeze down to .150". You may have to cut the longer rivets down prior to installation if you can only get the longer rivets, otherwise they will "pop" before they provide any clamping force. On this sled the 6 bottom rivets that hold the front bracket on needed to be enlarged to 1/4".
If the front support bracket that ties the two bolts together has loose or missing rivets you should consider removing it and inspecting the welds on the bulkhead behind it. Under severe use these welds will crack and should be repaired. You can see in the pictures below I built a new support bracket out of .100" chromoly that ties the front end together better. You do not have to get quite this elaborate but you should consider replacing the flimsy Factory support bracket with something that ties the steel A-Arm mount and the bulkhead together better. This is not a difficult task and should be considered if you have the plastic off. Notice the through bolts used to reattach the '05 front bumper. Make any needed repairs to cracks in the Steering Hoop at this time, these are prone to crack up near the top where all the steel tubes come together.
Here are some pics of another sled. I only have a few shots of the weld repairs I made to the chassis. Look for any cracks and repair them as needed. This sled had the steel mounting tabs reinforced when it was new before any rivets came loose. This isn't necessarily the best method but its how the sled showed up at the shop so we worked with what we had. The aluminum A-arm mounting tabs were cracked on this chassis but only a few of the rivets were loose. All cracks were welded and loose rivets were replaced.
For long bearing life in the drive train it is imperative to grease the bearings regularly. The following pics show how to line up the bearings properly in the Flangette and how to add a grease access hole to the Jack Shaft Bearing.
The A-Arm bushings must also be greased regularly. Here are a few ideas on how to make servicing these bearings easier without disassembly of the a-arm bushings. You can inject grease using a Needle Grease fitting available from your local parts store. There is a space between the bronze bushings that allow grease to squeeze throughout the bushing. Drill into this space using a .062" drill. You will be drilling near the weld where the tubing and bushing come together, sometimes this can be hard to drill so go slow and use a high quality bit. I broke a few drill bits making this modification, have a few extra on hand. Another good option is to drill the A-Arm with a larger hole and thread a normal Zerk Style grease fitting into each bushing. The zerks work good but are a little susceptible to getting knocked off during hard abusive trail riding. Before you drill the A-Arms for this modification make sure you realize how close this area is to the steel A-Arm attaching bracket. If you don't pay attention here you will have a small hole in your A-Arm but not be able to get grease into it without collapsing the suspension some.
For added reliability it's a good idea to install the Self Aligning bearing Polaris Part # 3514462 in the lower chain case. This bearing will help prevent the snap ring from blowing out the grove and cracking the chain case. Consider replacing the chain case at this time, chain cases are cheap and if there is any visible damage this is the time to change it. The upper and lower seals must be changed at this time. I also added the Extrovert drivers to this sled for added durability. Decide which gears will best fit your riding style and area, here are a few options. Trail Gears
The lower heim joint on the steering post is also an area that may need attention. Inspect the area of the bulkhead around the heim nut looking for cracks. It is best to repair this now before it starts to crack. Here is the Polaris Fix. On a few sleds we have blown out this section of the bulkhead. One of the easiest ways to fix this if it is already blown out is to use a 2.5" hole saw and drill an access hole in the forward facing plate of the bulkhead, this will give you access to the back side of the aluminum nut so you can make weld repairs. I have no pictures showing this repair.
While you have your chassis all apart now is a good time to check the condition of the Muffler Bracket rivets. These rivets loosen up over time and should be replaced with structural rivets. The muffler is fairly heavy and will loosen these rivets over time. If you don't plan to use the 440 muffler now is a good time to remove the bracket all together. Now is a good time to install the '06/'07 chassis support bracket that by the right knee. This bracket will help prevent the plastic from getting all bowed in when you hit it with your knee, it also strengthens the foot well area. If you have any cracks on the outer part of the footwell, consider making a steel l bracket and rivet it into place, welding these cracks will just crack again because of the thin aluminum in this area.
After you have made all the repairs and upgrades to the bulkhead and chassis you can reinstall the plastic. Use Polaris rivet # 7621467, you will need about 30 of these rivets just for reattaching the tub panels to the chassis. Use black silicone to caulk up all the holes between the tub and the chassis. A $5 tube of PermaTex works good and can get into all the tight areas much better than a large tube for a caulking gun. If some of the holes in the chassis or plastic are wollered out just move over 1" and drill a new hole for your rivet. Extra rivets can be added under the footwell for added support.
Now is a good time to inspect and replace all 4 motor mounts, these mounts do break over time and are not expensive to replace. Grease and reattach the A-Arms, Front Suspension and steering components. Consider the AkRacing Bolt Kit for your suspension mounting hardware. Reinstall the Track and all the Drive Axle components. Be very careful when installing the chaincase not to damage the new seals. Service and reinstall the rear skid into the chassis. If your shocks have not been serviced lately now is a good time to freshen them up and change the tune up as needed.
Now your sled is all back together and should be structurally sound for several thousand miles. I will add to this page additional information as it comes up.