How do I remove this plastic cap?
 

I am trying to mount a rear rack on my trek 7.2 but ive run into a problem. The mounting holes have these plastic caps jammed into them and I can not get them out for some reason. I have a trek 7.2FX.

Ive tried prying put I ended up cutting my finger.

http://bikeforums.net/attachment.php...hmentid=422104


any ideas?

Pliers?

I would guess that these are similar to the plastic end caps found on some flat bar type grips. It looks like there is a bit of plug extending outward around the circumference of the rack mount. I would carefully fit a flathead screwdriver behind the edge of the cap, and tap it from behind with a mallet. Once there is enough of a gap to grab, a pliers should be able to grasp and remove the cap. Just be careful not to let the screwdriver head contact the painted metal surface.

Got them! i tried the tapping with a mallet then pliers. worked like a charm!!! now a trip to the hardware store tomorrow to get the right screws!

find a friend with a healty finger and have him or her try it again. :)

Excellent, get that rack mounted up right!

Plastic tire levers are good for getting these plugs out. Screwdrivers can scratch the paint (although once you mount the rack the paint will probably get scratched anyway).

Don't forget to grease the threads, and to use flat and lockwashers where appropriate. Torque them firmly; a properly-torqued fastener should not need Loctite or similar to stay put. Any fender stays should be mounted outboard of the rack stays to minimize bending stress on the fasteners. Don't skimp on the fastener length; screws can be easily shortened for a just-right fit. Ideally at least one full thread should protrude from the nut/eyelet.

I suggest stainless (technically, corrosion resistant) hardware for its, well, corrosion resistance. And hex socket cap screws are superior to hex or Phillips head screws for this application, IMO.

+1 for stainless mounting hardware. Fastenal carries everything you will need in metric, allen (hex socket) head.

McMaster-Carr and surprisingly, many True-Value stores have a good selection.

Most Ace Hardware stores have a big stainless section. My usual dilemma is deciding what type of head I want on the fastener.

MCMaster-Carr has everything, but I always end up paying more for shipping than for the items.

+1 But be sure the lower bolt on the drive side doesn't protrude so far inside the dropout that it interferes with the chain shifting to or running on the smallest cog. The cog to dropout clearances can be pretty tight.

Same for Bolt Depot.

I have a 7.2 FX also and tried mounting a rear rack today. I have the very same problem that's gotten even worse. I couldn't get the stubborn things out using a screwdriver and small pliers so I came here, saw your thread and took your advice by lightly tapping from the opposite side with a screwdriver and hammer. I was able to get the cap about a third out when the top broke off! Now I have a plastic-filled bolt hole and I can't imagine a way to get that out. I stopped working on the other side as soon as saw the plug begin to separate. First of all, what's the point of making these little plastic caps so darn snug anyway? And second, how the heck does one get them out? Great bike but this little plug is a pain and only causes excessive cussing and paint scratches. Ugh. Frustrated.

Thanks in advance for any advice.
Here are some pics:
http://bikeforums.net/attachment.php...hmentid=483357http://bikeforums.net/attachment.php...hmentid=483358

I work in a Trek shop and hate those things. Cost cutting measure -- used to come with bolts installed, now those plastic bungs. I use vice-grips to start unscrewing them, and then finish by hand because it's faster. They are tapered, so once you get them started, they start turning with ease, but I think originally they are just jammed in there.

I often use my SAK blade as a drift punch like edge on the plug's outer rim and unthread a bit. once there's some clearance under the rim then pry off. Andy. Who also hates these stupid things.

If you've got bits stuck in, you've got two options, and both will end the same: punch it into the frame, or use a drill bit to remove it. A dull chisel (aka screwdriver) works well for removing them. A blunt, oblique force, and they usually come out in one go.

Thanks everyone for the suggestions. I'm thinking I may have to use a small drill bit to get it out but first I'm going to take it to the bike shop. I realize it's not mechanical and not a warranty issue but I can't help but think they'd help me out. Treks aren't exactly cheap!

if it is threaded , Which I expect .. you dont want to ruin that thread,

in fact Recommended .. take it to a bike shop and get the threads cleaned up by re tapping them before installing the bolts.

Thanks again for all the helpful suggestions. I was finally able to get those little plugs out. I used a small hook and pick tool set that I'd found at Harbor Freight for $1.99 and they did the trick. The right-angle tool was the most useful and with it I was able to dig out the stuck plastic bit by bit - you can see in the pic just some of the bits I had to pull out of the bolt hole. The other one came out a little easier. I also stopped at my bike shop when I was out for a ride to ask them about it - just out of curiosity and they acknowledged that Trek may have used a little too much adhesive on those caps. Using any adhesive for this little plastic cap is perplexing to me! ... but whatever. I finally got 'em out! Here's the assembled rack. I think it looks great.
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