Bicycle Mechanics - New cog/freewheel for Trek Cruiser classic

A couple of years ago, I bought my wife a Trek cruiser classic for her birthday. She doesn't ride it much because there's one hill between our neighborhood and the uni where she works that she can't pedal up comfortably.

It currently has a 16T cog on the back, and I want to switch to to an 18T to make the ride easier (it's only a mile to her office, so speed isn't an issue).

A google search has turned up several sources for coaster brake cogs--what is involved with changing the cog on a coaster brake hub?

(I've done plenty of work on derailleur bikes, but haven't seen a coaster brake since I gave up the old Schwinn Scrambler back in the late 70s.)

The cog is held on by a snap ring. Remove the ring by working a small flat blade screwdriver into one of the slots and pop the ring off. Then the cog should slide off. Slide the new cog on and work the snap ring back on with the same screwdriver. You may need to lengthen the chain a link. KT and Shimano coaster brake cogs are interchangeable, but KT cogs use 1/8" chain only.

Make the ride easier and put a 20 tooth on it.

i commute to work on cruisers myself and have a good feel for gear ratios. my normal cruiser is 46/19 (chainring/cog) and that is about normal. my full dressed cruiser runs 44/20 and that is low enough for moderate hills allthough not best for speed, but since you said speed wasn't a factor. what is the size of your front chainring? id go with a 20tooth cog, put it on as described above and you may need to add a few links of 1/8" chain if this shortens up your chain too much. if so, just use a chain breaker tool and once you pop off the master link with a screw driver or needel nose pliars, just add as many links as you added cog teeth. you may not need to add any chain, but be prepared to if you are going more than just a couple teeth bigger on the rear cog. its very easy to do so don't let it detour you from this project cuz the new gear ratio will be worth the few minutes work.

I counted 40 teeth on the chainring and 16 on the cog, for 65 gear inches. An 18-tooth cog would yield 58 gear inches, and 20 teeth would yield 52 gear inches.

I counted 40 teeth on the chainring and 16 on the cog, for 65 gear inches. An 18-tooth cog would yield 58 gear inches, and 20 teeth would yield 52 gear inches.

Choose, but choose wisely.

Thanks for the advice. I called the lbs to see if they could get a coaster brake cog, but they told me that the only way they could order one was as a complete rear wheel, so I ordered online. I went with 20 teeth, which after a quick test ride I think will be just about right:
http://farm4.static.flickr.com/3222/3065922001_bbdd28caf3.jpg?v=0

The only problem I have now is how to get the greasy fingerprints off the whitewall tires:
http://farm4.static.flickr.com/3188/3065923329_bc0a9a161e.jpg?v=0

That's after a wipe with 409. Any suggestions for removing the grease without attacking the sidewall?

Thanks for the advice. I called the lbs to see if they could get a coaster brake cog, but they told me that the only way they could order one was as a complete rear wheel, so I ordered online. I went with 20 teeth, which after a quick test ride I think will be just about right:


What a load of bull****. The largest bicycle parts wholesaler has a warehouse just up I-20 in Birmingham with loads of coaster brake rear cogs. I know, I just bought several from them, and their website shows hundreds more in stock. That shop was trying to rip you off on a level beyond reproach. If they aren't competent enough to swap a coaster brake rear cog, they ain't worth (expletive only way to express disgust).

That being said, I hope she enjoys the bike more.

I honestly don't think they were trying to rip me off--their answer was, "sorry, we can't get a cog without a wheel," not "that'll be $67.50 for a new wheel with the right size cog." They just weren't clever enough to google "coaster hub cog" and order one for $6.95 off the internet (like I did) and mark it up a buck or so to make the sale.

There's just not much of a bike market here. When I bought her the bike, I wound up buying it in Birmingham because the shop that used to be here had trouble ordering it from Trek (They went out of business not long after).

The only problem I have now is how to get the greasy fingerprints off the whitewall tires:
http://farm4.static.flickr.com/3188/3065923329_bc0a9a161e.jpg?v=0

That's after a wipe with 409. Any suggestions for removing the grease without attacking the sidewall?

Westly's Bleech-White. That's how it is spelt. Find it in an automotive department of a box store/hardware store or an auto parts store.

take the wheel back to the shop. Demand your $$$ back and tell them to look in either QBP, Hawley, SBS, J&B, catalogs If they refuse find another shop.

take the wheel back to the shop. Demand your $$$ back and tell them to look in either QBP, Hawley, SBS, J&B, catalogs If they refuse find another shop.

I didn't have the shop do any work. I called them asking for the cog, and when they couldn't get it, I ordered elsewhere. Hard to demand $$$ back when I didn't spend any.

Sadly, finding another shop isn't an option--they're the only store in town. There are some decent shops an hour away in Birmingham, but they're not within easy walking/biking distance.

the shop could only get you a cog if you got a new wheel. lame. glad you did end up finding what you needed though and may i add that is a fine bike you got for your wife. as for the whitewalls, i ride primarily only old cruisers (even commute on a cruiser) and i am a bashfull sucker for whitewalls. i usually just put some dish detergent on an old kitchen scrubber and add elbow grease to get grime off whitwall. if not, i then move up to a powder bleach like ajax to scub them clean. it may take a time or two at it.

you could also try a Mr Clean Magic Eraser

may i add that is a fine bike you got for your wife. as for the whitewalls, i ride primarily only old cruisers (even commute on a cruiser) and i am a bashfull sucker for whitewalls.

Thanks--I had a lot of fun shopping for her present that year. We got her a mountain bike a few years ago that was just never comfortable for her, and she likes the cruiser much better.

funny how things turn out like that. got a nice new mountain bike, full suspension in my living room i could ride anytime, but its too uncomfortable and the suspension on dry pavement is like riding a wet sponge. i will take my cruiser anyday of the week, and even started riding my 1951 schwinn spitfire ss cruiser to work again this week

heil the gearless!!! we can do more with one cog than many of you can with 7 or 8.