Tuesday, January 13, 2015
Installing a new gas tank on your motorcycle
You have just purchased a new aftermarket gas tank for your ride. Before you bodywork it and paint it there are certain steps that will keep your tank looking good for years to come and save time in the long run.
The first thing we suggest is to dry-fit your new gas tank. Whether it is a bolt-on reproduction for your model or a custom install, your new tank should be mounted to the bike to be sure there are no changes that are necessary. Be sure to bolt the tank on as will when installing it for good to make sure it sits properly and is aligned properly on the backbone of the bike. The tank should not be under stress to align hardware as over time this cause failure of the mount and likely a leak. Additionally you should check for clearance of your handlebars and risers from steering stop to steering stop. Also check that your fuel cap will not have any obstructions. Install the petcock to make sure that there is ample clearance between the bottom of the fuel tank so that the petcock valve can function and there is a clear path for the fuel line to approach your carburetor fuel inlet.
After checking for proper fitment, make any necessary changes to the tank or mounts. If there is any welding, cutting, or drilling now is the time to do this. Keep in mind that if you do make any changes to the tank, typically there is no returning the item if you have just purchased it, so be sure before making any type of alteration to your new tank. Fit the gas tank again after any alterations to be sure of fitment. Alterations at this point are relatively not very time consuming. However, if you wait until the tank is painted and filled with gas to realize that your petcock is going to be obstructed by your rear cylinder rocker box, you will be spending much more time to fix fitment issues.
The next step is to pressure test your gas tank. Follow our guide to pressure testing gas tanks if you are not 100% confident in testing your tank. Any leaks at this stage that go undetected could ultimately ruin your new paint job or even pose a fire hazard. Any small leaks or pinholes should be welded or soldered. Pressure test your tank again to be sure it is repaired properly. Again, double checking now will save you time.
Once you are sure that you have no leaks, all fuel tank manufacturers suggest sealing your tank with a quality fuel tank liner. Prep and line your fuel tank according to the instructions accompanying the fuel tank liner that you choose. We have an article on lining your tank using Red Kote. Bill Hirsch Products makes another tank liner and Kreem has a tank liner kit available to complete this step. Red Kote is the product we most frequently use in our custom build shop.
Your sealed tank can now be prepped for bodywork, bodyworked, primed, painted, and cleared. After your paint process is complete we suggest using our Neck Saver product. This product will keep any gasoline or fumes from getting under your new expensive paint job and bubbling it. We have seen this happen on many bikes. The Neck Saver product will save you the frustration and added work that a damaged paint job will cause.
Carefully install your petcock and cap. Install your tank as you did previously this time being mindful to not scratch or dent the tank. Quality masking tape in damage prone areas is a simple way to keep any mistakes from happening. Some blue medium strength Loctite is suggested for mounting hardware as motorcycles, especially V-twins, tend to vibrate bolts loose. Next attach your fuel line from the petcock to your carburetor. Use the proper inside diameter fuel line for the petcock outlet and fuel inlet on your carb. We suggest an inline fuel filter to keep any small debris that can enter your tank from making its way to your carb. Turn your petcock on and observe fuel flow. Check for leaks before starting the bike. When you're sure of no leaks and proper fuel flow it is time to start your bike.
Enjoy your new tank!
*Note: The Rullo Custom Cycles Frisco tank shown above was painted by Ryzart.