2018 Fatbob gas cap rattles
 

I love my 18' Fatbob, but the gas cap rattles (vibrates) when I accelerate. It's pretty noisy, mixes with the engine sound in an annoying way. Wondering if anyone else has experienced this and found an easy fix? I try tightening it, adjusting it, etc. but can't get rid o' the rattle. Would replace if I could find one that matches my industrial grey.

Can you explain better what part it is that rattles? I haven't heard anything (yet)

My '16 break out does this also. And yes it is correctly installed. It only goes on one way. I hear it and can see it s it will also rotate a bit. I know it is the cap as when I put my hand on it it stops. I have been told that this is normal. I plan on installing a chrome flush mount, pop up one later this year.

It's not normal. Even the OEM caps on my old bike don't rattle and my engine is solid mounted with no counter balance shafts.

I have replaced them with pop ups just for improved appearance.

Ive read more than one post on here about the gas cap rattling on the new FatBob. Mine doesn’t yet, but it seems to happen.

Believe the other posters that had this issue had the gas cap replaced under warranty, believe it or not.

I had the same issue on my Fat Bob ... annoying as hell. It was warrantied without question by my local dealer.

Yep, I had that exact issue, it'd buzz like an angry hornet at 2500 rpms. They replaced it under warranty.

Mine didn't.... Until I went stage 2. Now its pretty annoying. Ill check if they will cover it under warranty, that would be awesome.

Thanks for the replies.

@BlackSP - not sure which part of the cap rattles, but when I lay my hand on it lightly while riding, it stops the rattle.

Good to know that it's under warrenty. Will call me dealer in the morning.

Well a happy ending -

Stopped by my local dealer today and swapped out the gas cap with a new one for free thanks to the warrenty. No buzz during the ride home.

Update - been riding 13 days straight since gas cap swap. No rattle! woo hoo!

The way the cap freely moves after securing with the first snap it would appear some noise might be inevitable. I don't hear anything because I wear full face with ear plugs.

I wear full face with air pods, could still hear it especially when accelorating. It was really annoying because I like to hear my motor as is, not with added noise vibration. The replacement cap is exactly the same as the original cap that came with the bike - minus the vibration noise.

I have an 18 Fatboy 114 my gas cap rattles like crazy. Going to have the dealer replace it.

Jim

Look under cap and on outer edge where cap rotates use a hammer and punch to indent. Problem fixed...

spraying silicone under where cap rotates helps also...I used pigspit

I've had 3 different late model Harley's that have done this, including my 2018 Lowrider. All 3 replaced under warranty. If you rock the cap you can hear it really well. It's funny some dealers still scratch their heads and say they've never heard one do that. I always show them the movement when I need one replaced so there's no question.

The dealer here has not received any literature on it from Harley so they won't replace mine under warranty. It seems like Dealers in New Mexico, or at lest the one in Santa Fe, NM, don't get any of the service bulletins or recalls that everyone else gets. They looked at me like I was crazy for even mentioning that they are replaced under warranty. Guess I will have to solve the issue on my own or get a different gas cap. BS...

Go back to the dealer and show them the service bulletin number. Then they have to look it up and then they will see. I once owned a 2004 Mazda RX8 that the shops could not get my new tires balanced. it turned out to be a special mathematical formula used in conjunction with the balancing of the tire. The local Mazda shop had no idea that this existed. I got the procedure from a fellow forum member and printed out the service bulletin and it worked like a charm and the Mazda service center learned something new!

Same here a dealer(not mine) replaced mine free but I paid a few bucks extra and got a black one but I had shimmed and used paper gaskets on everything that could buzz,rattle or hum before putting my hand on the gas cap and the rattle stopped.

I can't find any service bulletins on this issue. Maybe I am looking in the wrong places but I have not been able to produce a bulletin number for them. Even though I was unable to give them the bulletin, I finally asked to speak to the service manager, who knows me pretty well from my passed Sportster engine project, and he agreed to replace it under warranty after he molested my gas cap then the one on the Fat Bob on the showroom floor as well as after reading some of these posts on the issue. Other than hearing about it from me and after reading this thread, no one in service department here has heard of it and they have not seen any service bulletins on it, or at least that's what he and the tech said. The tech was all for replacing it and was totally up for it once he felt the movement in my cap. If you have a bulletin number I can take to them just to inform them and to further support my case and prove that I'm not just crazy I would greatly appreciate it. If not it's fine because they are replacing it either way. Once I have the replacement cap, I'm going to try some of the home remedies to fix the rattle on the original cap that way if the new one begins to rattle I will swap back to the original. I will eventually switch to a flush mount gas cap but for now, the free new OEM gas cap will have to do.

Good to hear man.

I didn't have any sort of service bulletin or anything. I just said "the gas cap rattles" and my dealer said "we'll swap it out for you under warranty" and that was that. So it may or may not be a Harley policy, or it might be down to your dealer's discretion I guess.

Same here just turned up ,told them and they swapped it out.
I got a black one so I had to pay a couple of bucks for the price difference.

I didn't think there was one since I couldn't turn it up anywhere no matter how hard I searched. Once I told them that other dealers are replacing them and showed the manager the posts on the issue he was satisfied with the documentation of it and overrode his service writer's decision of not to replace it. The service writer just gave a stupid look after that.

I just swapped mine to the flush gas cap. no issues.


https://cimg0.ibsrv.net/gimg/www.hdf...46fb976380.jpg
https://cimg3.ibsrv.net/gimg/www.hdf...22d8fb0431.jpg

Mine rattled, read on here in one of the topics to turn it at least 7 - 10 "clicks", tried it and no more rattles. Cost nothing, worth a try.

There are some nice options for gas caps on eBay for $10 or so delivered that fit and do the job well. Yeah, They are from China, but well made from CNC'ed billet, functional, don't rattle and avoid the HD $100 gas cap tax. Couple of examples below:

Flush mount pop up

Rough Crafts style knockoff

Thanks for the advice. I read that as well and have been doing it and it helped for about a week but now I can turn and turn and turn it some more and it still just rattles like a rattle snake. I'm going to use the replacement cap they ordered for me until it starts rattling again and will replace that with a flush mount gas cap. I like the look of them better anyway and it will resolve the rattling so it's a win win for me.

Thanks for the suggestions and links. I will check them out.

@sleepingpanda which flush mount is that? HD doesn't have one listen that will fit. If you can share a link, I'd really appreciate it.

Same noise on 2018 FXLR
 

My gas cap on my new bike rattles too. It's really loud and annoying. This is the 10th HD I've owned and none of the others had this problem. I'm going to ask them to replace it when I go in for the first service.

Just took my Sport Glide in for 1k service. Had them replace my gas cap. New one lasted about 25 miles. I think this one is even worse.

This has started happening on my Breakout. Going to pop to the dealer next week and see if i can get it replaced. Might see if i can go with the locking fuel cap.

Hi Guys

I m quite new in the forum . I have had the same issue and more :(

I have the same problem with my Heritage. My dealer here in the UK would not swap it under warranty because "the new one would be just the same".
He did suggest buying a pair of caps from the accessories catalogue, that would have cost about £100.
Things like that will put me off buying a Harley when I come to change bikes. I typically change bike every 18 months, and of course I suffer all the depreciation and the dealer makes all the money.
Their loss.

The solution is quite simple actually. Just take a piece of an o-ring, about 1 cm and push it in per the image below.

https://cimg0.ibsrv.net/gimg/www.hdf...8943485490.jpg
gas cap rattle

That sucks. I'm in the UK and my dealer offered to replace the one on my Breakout. Decided not to bother as i'd planned to switch it out for a black one. Ended up buying the Diamond Black Cap. Looks much better on my bike and no more rattle.

https://cimg8.ibsrv.net/gimg/www.hdf...051b119641.jpg

The outer piece of the cap, (black, gray, chrome whatever) is simple a cover to the actual cap. Turn the cap over on a padded surface and stake the cap along the edge that is already crimped, tightening the crimp up some. super easy to do, and has been the solution for years.......

Mine rattled after I put the first tank of gas in it. Took it to the dealer and this is what they did. Hasn't rattled since.

For what it's worth, the crimping or other solutions to fix it yourself seems to be the way to go. I've had mine replaced once so far and it just rattles anyway. Replacing the gas cap with another OEM gas cap doesn't resolve the issue for long before it starts to rattle as well so it's just a waste of time for everyone.