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Hi all, new member here.
I've acquired a 99 fatboy and am trying to install new intake gaskets. The bike was running pretty bad and I found that it was sucking a lot of air around the intake. It should have been a pretty straightforward fix but I'm having a problem with one bolt wanting to crossthread. Is there an easy way to clean up the threads without having to pull the motor out and retap. Not a lot of room in there.
I'm on the tail end of refreshing the top end on my bike, my first time doing it. Had several instances bite me in the *** for not cleaning the threads before assembly and had to disassemble a lot of things to do that. Take your intake off and stuff the holes, i used terrycloth shop rags. If the threads are completely mashed use a starting tap to get the first couple of threads going. I used motor oil on the tap for lubrication. Only turn the tap about a half a turn in then back it out a little. Then repeat a little further in. Keep backing it out as you go further in because you may catch a burr and drag it through your threads. I didn't go that far until I switched to a bottoming tap seeing as the hole you are tapping doesn't go straight through. Blow the hole out occasionally and keep using the bottoming tap. You will at some point feel your tap bottom out by getting stiff to turn. Stop at this point or you'll strip the threads out. Do all 4 for safety sake. I put a little motor oil on the threads of the bolts before I reassembled mine.
I'm on the tail end of refreshing the top end on my bike, my first time doing it. Had several instances bite me in the *** for not cleaning the threads before assembly and had to disassemble a lot of things to do that. Take your intake off and stuff the holes, i used terrycloth shop rags. If the threads are completely mashed use a starting tap to get the first couple of threads going. I used motor oil on the tap for lubrication. Only turn the tap about a half a turn in then back it out a little. Then repeat a little further in. Keep backing it out as you go further in because you may catch a burr and drag it through your threads. I didn't go that far until I switched to a bottoming tap seeing as the hole you are tapping doesn't go straight through. Blow the hole out occasionally and keep using the bottoming tap. You will at some point feel your tap bottom out by getting stiff to turn. Stop at this point or you'll strip the threads out. Do all 4 for safety sake. I put a little motor oil on the threads of the bolts before I reassembled mine.
Thanks for the reply, what size tap are the intake bolts off hand, do you remember?
I bought a thread cleaning kit. Taps are not designed to "clean" threads, they are designed to cut threads. A thread cleaning tap looks like a pipe thread tap kinda, the ends tapered just a little so that it gets into good threads before biting.
In my own defense I've always found it more difficult to clean threads if the first few have been damaged. I've always run a starting tap in the hole to get the damaged threads aligned with the good ones. Then I ran the bottoming tap through them to finish the job. The bottoming tap I used is what you described as a shorter tap with not much of a leading edge on it. If the threads are good you will be able to spin that tap through the threads with your fingers so it's not necessarily cutting new threads. Except for the first few damaged ones of course. Everyone has a different approach and I offered mine that's all
Great info, I was worried I might have to pull the motor out and retap but I'm gonna get the bottoming or tapered tap in it and get em cleaned and hopefully get it back together for a few more rides before winter. Thanks guys
I bought a thread cleaning kit. Taps are not designed to "clean" threads, they are designed to cut threads. A thread cleaning tap looks like a pipe thread tap kinda, the ends tapered just a little so that it gets into good threads before biting.
Yeah, thread chasers or re-threading kit. They aren't expensive but not so easy to find as taps. They re-form the threads rather than cut material. Taps will work though if you're careful. Just depends on what you're working with so far as damage and material.
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Intake issues
