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Discussion Starter · #1 ·
I am a big rider - and I used to be a lot stronger than I am now.

I rode a redline monocog for a long time - then had a Jabberwocky - now I have a SS pugs 32X21 and a Jamis Kromo (28X14)

Most of the trails that I ride are great for SS with some short climbs that are just to loose to get up (even with the pugs and tractor 22X36). In almost all of the bike I have broken drive train issues.

I have spun threads on the freewheel - bent chain rings- broken chains (not at the master link!) - and busted pawls in the hub. Not even to mention the number of times I pulled the wheel out of alignment (did it this morning on the ride). I have chain tugs in place - but the wheel still moved enough to kick the chain off the cog.

I know there are people who are stronger than I am - I weigh 240 lbs (add 5-8 for camel-back).

Is it because I am trying to power my fat ass - adding a lot of torque to the frame - over short bursts of power? Would the 8th grade 180 pound me not brake as much stuff?
 

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SS Pusher Man
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My understanding is that breaking chains has more to do with poor chainline than by torque.

Look at some of the Pro Roadies that are Sprinter Specialists....the amount of torque they are putting on 11 speed chains and they are not breaking.

As for pulling the wheel out of alignment.....find a frame that does no use horizontal dropouts. So many more choices these days with EBB's or Swinging Dropouts.
 

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Discussion Starter · #4 ·
I have used a lot of stuff - mostly Shimano LX level model - I cannot afford the higher zoot stuff.

I also use a lot of older 9 speed stuff - new old stock. (I have two old ringle through axle rear hubs which I love). I have learned to pay more attention to chain line from riding my fixed gear - I never thought about it until then. But it is spot on right now.
I have never had a problem on the road putting down power in a sprint or up any grade.. it is the short steep rocky ups where I have great traction... ping...crap. The Pugs has epic traction!!

The question came to me this morning (hence the post) - those sprinters who put out 1000 watts - only weight 140 to 170 lbs at the most. I am almost twice the rider weight - and I can put down the watts for short bursts (I was a shot putter and have very quick legs).
Here is the analogy that I see... Put a Volkswagen GTI motor in a delivery truck - you have plenty of power but the torque is all wrong. The load on the motor trying to get the thing moving would kill the transmission - or the motor... Power bands are all wrong.

I have not had a "new" bike in 10 years so most parts that I have are recycled or new old stock of what was good two years ago. If it is just parts quality - then well that can be fixed with time.
The pugs is running a SLX rear hub with a 21 tooth SS cog on the cassette with spacers (cog is form the redline). The Jamis has a 14 tooth BMX cog and a unbranded rear hub (most likely formula).

I think the moral is going to be "Save your money and buy better stuff."

But that still does not solve my torque problem...
 

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It seems almost counterintuitive, but the lower gearing on a mountain bike single speed will put a lot more force on the rear hub than the typical gearing of a road or fixed gear bike. That's why you use a lower gear ratio, 'cause it gives you better mechanical advantage. More torque.

But anyway, I am 99.9% positive that you can't break a White Industries freewheel. So that would solve your busted pawls issue. You probably break the chainrings and chain when the wheel goes out of alignment, so you need to fix that problem and the rest will go away. Maybe a different frame, a hub that tightens down better, or better chain tugs. Chain tugs don't do much on the brake side though - you could shift the wheel out of alignment on the brake side and the results would be the same. A Kona or Salsa with sliding dropouts might be the ticket.
 

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Better components = stronger. No two ways about it. Shimano hubs have been known to blow up. Lots of threads on this. Shimano/ACS FW's aren't that great.

Unfortunately, things that will solve your issues will cost more money. But looking at it from a perspective of not having to replace those parts as often, you'll probably come out ahead. For a stout set up, I'd probably go Surly 36h hub with White Ind FW, maybe a 5-bolt chainring/cranks, Phil BB. I'd probably regear the Kromo with bigger gears than the 28x14. Smaller gears mean less chain wrap, more kink in the chain, which *could* be causing the chain issues.

Also, track sprinters ain't no 150lb weenies.

 

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Discussion Starter · #7 ·
I was thinking road race sprinters - but I have met some of the 200M guys working out at the velodrome.. they are more my brethren than road racers!

The Jamis is really just for riding with my son (7). I have not taken it for a ride longer than 6 miles other than laps at the BMX track. It does not really have a seat to speak of and it is really fun as a trials bike.
 

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Weinerts,

I had the wheel move on me now and then with my steel Jamis, I sanded off the paint and bought a XT quick release and have not had an issue since. I am 200lbs with out a camelback on
 

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1*14*29*2.1 & 1*1*29*2.4
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My understanding is yes...weight is a big issue. Gearing also, and possibly to some extent like phsycle said, the choice of ring and sprocket size. After owning a rohloff and going through the torque limit specs, they are based on chainring size/sprocket size, and rider weight. I guess crank length would be a factor to some degree. Track cyclists have their torque "watered down" and converted to power via high speed gearing. You have the opposite happening so will be prone to over torquing. With the rohloff, rider weight over 100kg changes the warrantee and the rider needs to go up 2 teeth on the chainring (from memory). This will reduce torque at the hub, at least. From what i have read, larger rings and sprockets reduce the stress on the chain too. If you went to a SS specific chain and ring/sprocket set up I think that may be your best bet...with larger diameters and higher gearing.
 

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Discussion Starter · #10 ·
Cool. I am glad nobody suggested losing weight. It is ironic how people would rather spend money on parts (me included) rather than change their behavior.

The funny part is that I teach behavioral psychology......
 

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I may be thin for my height but I'm still 200lbs + gear and water. The only thing I have come close to busting on my bike was the bottom bracket. Maybe I just don't know how to really HTFU as much as others.

and no, my bike isn't nearly as shmancy as some of the bikes seen on this forum.
 

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I concur with Shimano QR skewers, I had DT expensive looking QR that was a junk. I admit most of my equipment is craigslist, but I do buy chain, ring, cogs (high stress parts) at lbs/etailers brand new. Cheap self wants to recycle chain, but I busted enough at Shimano replacement links (outer plate snapped off many a times), I don't do that on SS.
 

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Discussion Starter · #13 ·
Here she is now

Here is the nimble beast.

Shimano slx rear hub - 21 tooth cog - 9 speed chain - 32 tooth front ring - Raceface cranks 100mm bottom bracket.

Graceful fat sheeba rims Larry 27 tpi tires - tubeless running 10 lbs in back and about 8 in front.
 

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Discussion Starter · #14 ·
Oh and right now i weigh ~240 lbs and am 6 foot tall.
 
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