Introduction: Remove Seized & Stripped Screws From Motorcycle Engine Covers
Hello! Motorcycles are still new to me, and for my first project (after learning to ride, of course), involves getting to know my bike. What better way to familiarize myself with the parts of the engine than to replace all the old, seized screws from the side covers? I picked up a "complete set" of shiny new allen bolts from 4into1, but quickly realized it would be harder than expected to remove the old screws from my 1975 Honda CB200T.
Not only were many of them seized, but they are JIS (Japanese version of Phillips) screws, which are prone to stripping if you use the wrong (ie regular Phillips) bit. I definitely stripped at least one screw before even conceiving of the other steps in this guide.
So whether you're stuck mid-process or if you're thinking of attempting screw replacement on your vintage motorcycle, these techniques will help you deal with stripped and seized screws.
Step 1: Tools & Materials
This is a nice project to ease into-- you don't need all the tools at once to get started. Start with the easy-to-access screws and work up to the removal of the footpegs required to access certain screws.
- wrenches for removing parts to gain access to obscured screws
- flathead screwdriver
- allen keys and/or allen screwdrivers that fit replacement screws
- JIS T-handle screwdriver
- manual impact driver
- Dremel or other rotary tool with cutoff disc
- eye protection
- electric impact driver
- rags/paper towels
- left handed drill bits (if all else fails) and standard power drill
Step 2: Apply Penetrating Oil
About a week before attempting to remove any screws, apply penetrating oil to each one, as well as to the bolts holding on the footpegs (since we'll be removing them to access certain screws). Ride your bike around and get the engine nice and hot. Repeat 3-5 times over the course of the week so the oil has a chance to seep into the threads.
Step 3: Use the Right Bit for the Job
Before mangling your screws with a standard Phillips screwdriver, trust me that it really does make a huge difference to start out with a JIS bit in your screwdriver. These screws are pretty soft and very stuck, which is a combo that easily leads to stripped heads.
I ordered a three-bit T-handle JIS screwdriver from Amazon that worked perfectly for two thirds of the screws on my engine covers. If you are a bit stronger than I, you may get away with a regular shaped JIS screwdriver.
But if this driver strips your screw heads, don't worry. Next up we'll introduce more and more drastic methods for getting that sucker outta there.
Step 4: Try a Manual Impact Driver
A manual impact driver turns with high torque when it is struck with a hammer. Yours might work differently, but mine is dual direction and has to be twisted slightly in the direction you wish to turn the screw before striking a few blows with a hammer. Mine has standard Phillips bits since I couldn't find JIS bits for it or a JIS manual impact driver.
Since I'm not using the correct bit anymore and the screw is likely already mildly stripped, it will now likely either release or strip entirely. If it's the latter, don't worry! We're not giving up yet.
Step 5: Stripped? Cut a Slot
To work with a stripped screw head, the next step is to cut a slot in it with a rotary tool and cutoff wheel. Be sure to wear eye protection, as the cutoff wheels have a tendency to break and send shards in every direction. Hold the wheel as perpendicular to the screw head as possible, and dig in to cut a new slot across the head. This gives you better leverage.
Now you can use a flat bit and your manual impact driver to try again, or bust out the electric one in the next step.
Step 6: Electric Impact Driver
My friend happened to have an electric impact driver to lend me, which removed the last remaining stubborn screws from the engine covers. However this tool is really jumpy, and scratched the metal of the covers in a few places. If you don't have access to one, but have a standard drill, the left handed drill bits in the next step are a suitable alternative route, cost wise.
Step 7: More Drastic Measures
Left handed drill bits have threads cut reverse from normal drill bits, and will actually start backing your screws out as you drive them in. My bike did not require this more drastic step but your screws may be more stripped than mine.
When I mentioned I was working on a tutorial on this topic, many more suggestions came in so I will share them here as well!
- Heating with a torch, rapping with a hammer
- Drill and re-tap
- Screw extractor/remover set
- Take it to a shop! If all else fails, ask for help from a professional.
Step 8: All Done!
When the screw finally does come out, here's what you can do to prevent that situation from happening again! Use some heat resistant anti-seize lubricant on the threads of the new screws when you install them.
My new screw set was one screw shy of what I needed, and two of the screws were too long and needed to be ground down to fit. But now I know my bike a lot better and will be ready to take on more advanced repairs in the future!
Do you have an experience with stripped or seized screws to share? Post a comment below!