Mechanical questions on coaster brakes
Could I please get a "coaster brake expert" to check post #188 in thread:
I've posted chain stretch, crank breakage, and aluminum frame durability questions in that message concerning coaster brake bikes. Perhaps I should have put it in this forum? In any case, I'd really like to have some professional opinions.
Thanks in advance for your patience with this newbie!
At least for me, that link didn't work - it got abbreviated somewhere.
Here's the link:
Let's make it easy: Here's the post:
COMMENT: The Townie offers one advantage that other "cruiser" style bikes don't. I'm 6'2" tall, and on my current exercise bike/cruiser (A Dyno-Glide), the stock seat post can't be extended adequately to provide proper seat height. Since the original seat post immediately bent at full extension, I've replaced it with an industrial, stainless-steel pipe (with a brass shim to make it fit the seat tube). Even this is beginning to bend! With the Townie, the gusseted seat tube extension above the upper frame tube allows proper seat height with their stock seat-post! The few added inches of braced, seat tube extension make the difference. This is NOT a trivial issue for taller & heavier riders, who are poorly served by conventional cruisers. Unfortunately, good double-diamond frames with coaster brake hubs (like the old Schwinn Racer) are no longer available. This means that the ONLY currently-available frame with a coaster hub that will fit larger riders is the Townie (to the best of my knowledge..) If I'm mistaken, please let me know!
QUESTION ONE: The design of the Townie requires an exceptionally long distance between the bottom bracket and the rear hub (significantly longer than double-diamond or cruiser frames). Is chain stretch a major issue for the Townie? I ask this question because I'm frequently having to adjust the chain tension on my Dyno-Glide as I pump during exercise. About once a month, the chain gets stretched to the point where I either readjust the tension or it begins jumping gears.
QUESTION TWO: I've also broken the crank once on my Dyno-Glide (just twisted that puppy right in two in the middle of the bottom bracket!). I see that the Townie has a cotterless crank in aluminum. Since the steel ashtaubla crank on the Dyno-Glide didn't stand up to my stresses, will the aluminum crankset on the Townie be adequately robust? I'd like to hear from heaver riders who have purchased and used Townies for some period of time.
QUESTION THREE: I've never owned an aluminum frame before. The steel frame on my current Dyno-Glide cruiser flexes noticably when I get down on it. Is there any reliabiliby problem with aluminum frames in general (or the Townie's in particular) that I should consider prior to purchase? Since everybody's probably wondering by now just how monsterous I am (broken cranks, stretched chains...), I'm currently at 260#. In spite of this weight, I have muscular legs and walk, run, and/or ride daily. I used to ride double-diamond frame 10-speeds, but now stick with coaster brake hubs for reliability. Again, I'd be interested in hearing heavier riders' experiences with the Townie.
Thanks in advance for being gentle and helpful with me on this, my first post at BikeForums.
I can never pass up a chance to chant the coaster brake mantra 8-) But, it seems as though you're more concerned about the bike than the brake. First let me say that I'm 6'4", 250 lbs, and for us big folk, much of what's available component-wise, on low-cost bikes is unsuitable. The stuff may work for awhile but it'll break or bend sooner or later if you ride with any frequency or for any distance....You've already discovered this with the 'one-piece' crank.
Originally Posted by FarHorizon
I know nothing about cruiser-style bikes so won't comment except to say that I don't like the ride position. I prefer a steel frame. I have a Steamroller (4130 CrMo) which flexes in the BB (actually seattube/downtube/chainstays) when I climb but is still strong and fun to ride. My other bike is a Rodriguez made from Tru-Temper OX Platinum (steel) which is frighteningly stiff.
With regards to chain stretch....I'm guessing that most of your monthly adjustments are related to rear axle slip rather than to stretch....this is a problem I've had too. I would recommend a pair of 'tug nuts' for any bike you ride.
Now to the important part ... coaster brake ;-) I feel it is worth looking for an older Sachs (or Fichtel & Sachs) coaster. Have someone refurb it and learn to take it apart and clean/lube once a year. If used with a front brake (and I highly recommend it if you live in a hilly area) that coaster should last the rest of your life....and kid's life.
If you must ride a 'modern' coaster brake just check it and service it more often....They will work... I still don't like them.
To sum it up, I'm not sure you're going to find an 'off-the-shelf' bike that's going to work in the long run. I have a friend about your size who tried to find an affordable bike that would hold up to his commute but just kept throwing money at it (in the form of OEM component replacement) until he learned to build a bike (using a steamroller frame) for himself.
I hope this helps alittle...
EXCELLENT! Thanks for the good info & prompt reply!
You're exactly right on the chain stretch - I'm familiar with tug-nuts, but never thought of retrofitting them to existing frames. Where would one purchase just the tug-nut pack? I could add them to any bike I wanted by some "do-it-yourself" Dremel work.
Does anyone make frames for coasters? Other than the currently manufactured frames, the only other option I see is to buy a frame designed for multiple gears and cold-set the stays to the proper width for a coaster brake.
Where would one get the coaster brakes that you mention? I'd probably need to buy an entire used bike (e-Bay?) just to get the rear hub?
Thanks again for the prompt reply and good info!
Schwinn makes a SS bike with a coaster brake made from steel and a bit more expensive one made of alloy. I use a steel one with a nitto moustache bar and a brooks b-17 seat for my everyday commuter. It is heavy but im pretty sure it would stand up to a big person, im 5'9 and 190. Steel SS runs about 200 bucks, alloy 250. I was lucky enough mine is an older model and it is black. I like black. BTW, if you do buy one of the schwinns see if the dealer can hook u up on a seat, different tires, and a different handlebar-- a real seat/ flat mountain bike bar, and 1.75 and bigger mtn bike tires will change the whole bike for the better. Unless of course you like to ride completely upright. OK im rambling on, obviously time to goto bed.
Another good option would be to find a Van Dessel Straight up, 21 pound aluminum cb bike-- they are always out of stock but u seem em on ebay from time to time. Van dessel's web page is down maybe they are finally getting off their ass and making some more bikes.
"The expanded 2005 product line includes road, time trial / triathlon, cyclocross, XC mountain bike, and city bike models as well as the updated Country Road Bob.
The new website with complete details will be up very shortly!"
Last edited by kurremkarm; 01-05-05 at 05:08 AM.
my friend pat quinn is 6ft 310# and he races bmx. he had to switch to redline 3 piece monster cranks to get rid of some scary flex in the drivetrain, but they work for him. the only complaint he has with them is they require a wider stance, or tread, than most cranks. also, i'm not sure, but they might only fit in a large american bottom bracket shell that fits one piece cranks.
regarding aluminum, someone of your size would probubly end up cracking a aluminum frame unless it was made quite burly for thrashing purposes.
one frame that will fit a coasterbrake rear hub is here: http://www.firemansbikes.com/ they are known for having a quality product.
just about any bike with a rear facing dropout can benefit from a set of chain tensioners typically used on bmx bikes. my favorite are the redline chain tensioners.