Bicycle Mechanics - No need for the large gear ring

I am a weak rider and pretty much never use the large ring. I stay in the 38 tooth ring and normally don't go past the 5 th gear in the rear on a 8 speed bike. I am thinking about getting rid of the front derailer because I have to trim it when I go into the 5th gear on the back (did I mention that I might be lazy). If I get rid of the derailer will the chain start to rub on the large ring when I go to the 8th gear? If so can I remove the large ring and just have the 38 tooth ring which would make the bike a true 8 speed.

I am currently doing hill repeats and have not shifted from the 38/28 combo for about a month now. I need to go to an even lower gear because my cadence on a 5% grade in only about 50 rpm. Up the hill at 5 mph and down at 30 mph while coasting and no I don't want to go any faster down the hill.

Am I missing something or can I just ditch the big ring and its associated parts?

You can ditch the front derailleur easy. What kind of shifter is it--is it integrated to the brake lever, or stand-alone (like bar-end)? It may be annoying to if you can't remove an non-functional shifter, but that's up to you.

You can remove the large ring, too, but there's a catch. You'll need shorter, BMX/single-speed chainring bolts (because the thickness of the large ring will be removed). Here's an example: http://cgi.ebay.com/Odyssey-Silver-BMX-ChainRing-Bolts_W0QQitemZ280229632277QQihZ018QQcategoryZ48843QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

With the larger ring missing, you could shorten the chain, though it's not necessary. Use this method: http://sheldonbrown.com/derailer-adjustment.html#chain

One caveat - you may start dropping the chain off the front chainring without a derailleur, particularly if your chainrings are ramped and pinned.

One caveat - you may start dropping the chain off the front chainring without a derailleur, particularly if your chainrings are ramped and pinned.

I've heard this line a few times on here. I really don't get it. Why would it suddenly start dropping with the absence of the outer ring and front derailleur?

Keep riding. Try the harder gears a little at a time. You will get faster and stronger.

I've heard this line a few times on here. I really don't get it. Why would it suddenly start dropping with the absence of the outer ring and front derailleur?
Certain situations, like hitting a bump while pedaling in 38x12 or 38x(biggest), might try to throw the chain off of the 38 ring. Right now your big ring and derailer prevent that from happening.

If you ditch the big ring, and you find your bike throwing the chain off of the outside of the chainring, consider putting a bash guard where the big ring used to be.

You should be able to adjust the derailer to keep it from requiring trim across the cassette, if that's your only problem with your current setup.

The derailleur helps to guide the chain and keep it on. When I tried downhill mountainbiking, I had neglected to put some kind of chain watcher on the front and kept dropping the chain during practice. At a friend's suggestion, I went to the bike shop and got a broken front derailleur from them, which I bent to my liking and it kept the chain on pretty well.

Thanks for the insight. I dislike dropping the chain more than I dislike having to trim the derailer.

I like the idea of riding higher gears and getting stronger but for the last 3 years of riding I have not seen the big jump in performance. I am in much better condition now than I was 3 years ago so I will just keep pushing and hope for the best.

Keep riding. Try the harder gears a little at a time. You will get faster and stronger.

+ 1

... Brad