Discussion in 'Transmission / Drivetrain' started by HeadSmess, Feb 2, 2012.

  1. HeadSmess

    HeadSmess Well-Known Member

    i was window shopping the other day, and couldnt help but notice the sexy toothed belt on a ridiculously overpriced bike in the local overcharging bike shop.

    i really want to go in and start asking awkward questions...what are the advantages of a belt drive? and how do you justify the $2500 price tag on a single speed beach cruiser?

    ok, so it isnt messy.

    thats one. any others?

    lets see now... a chain is 98% efficient. you can remove or add links to a chain. chain and sprockets are readily available. and my chains are spotless because i wash all the oil off them before using them.

    a belt just doesnt come close. except maybe when dealing with grit and sand. and sand between belt and pulley equals death in my experience anyway...

    with the limited power my legs produce, id like as much power transferring to the wheel as possible. nothing else matches the chains 98% efficiency...

    think id get kicked out? :jester:

    i think im banned anyway from when i almost had a fit when he tried charging me $16 for just the inner brake cable...

  2. Max-M

    Max-M Member

    Funny post, HeadsMess!

    A $2,500 single-speed beach cruiser?! Yikes. I thought that the $350US price tag on my 2012 Giant "Simple Single" was pricey (bought new for my latest 4-stroke build). But the Giant's well worth it; I'll never use an inexpensive, no-name, pretty-but-sh***y bicycle again.

    I think that the idea of drive belts is intriguing, but the advantages of chain are too many to get me to look into belts too seriously.

    Also, like you, I don't have an oil-spattering problem with my #41 chains because I clean them well with soap and water before installing them. I wouldn't soak a chain in gasoline to clean it because that would certainly remove too much of its factory lubrication. The soap and water process leaves enough lube in the inner workings of the chain, in my experience. I rarely get my chain wet (I'm not a rain rider), so I think this method is OK in terms of proper chain movement and preventing rust. At least it's worked out fine in my first couple of years in the MB hobby.

    But I've been curious about what others' feelings are on the chain lubrication issue, and what they do in practice...
    Last edited: Feb 2, 2012
  3. curtisfox

    curtisfox Member

    Want a good chain lube find Try-Flow
    About the belt stop and think the harlys use them and most of the cars have them for timming belts. They are strong I have a twin blade mower deck on my lawn tractor that has one to keep the blades in time. Unbelevable what you can hit and not break. I have bent 3/4" shafts and not break it............Curt
  4. If we are talking flat belts or V-belts then, hands down, the chain is much more efficient. The old time flat belts slip a little and V-belts not only slip, they also experience friction due to differential speeds between the top, middle, and bottom of the belt. The V shape is how they work as well as they do and also why they build heat and lose some efficiency. The geared belt, also called a Gilmer belt, is a different kettle of fish altogether. They are used in almost every modern overhead cam auto engine for timing belts, including engines that will self destruct if the valve timing is too far off(valves and pistons will hit). They do not slip anymore than a chain does and their efficiency is very similar to a chain. They don't stretch because they are made with modern reinforcement cord material like Kevlar. You mentioned that getting sand on a belt will cause wear, the same is true of sand in a chain. On the other hand, moisture will cause corrosion in a steel chain, but the geared belt is unaffected by moisture. I have owned both chain drive(Staton) and geared belt drive(Golden Eagles Bike Engine) motored bikes and I will say the geared belt drive is smoother, quieter, and has less maintenance involved. Chain wears and stretches, belts wear, but do not stretch. I have a feeling that a good quality chain will outlast a belt, but the belts do last a very long time if they are properly adjusted in the first place and kept relatively clean.

    I suspect the high price of the belt drive bicycle you complained of has little to do with whether it is chain or belt drive. I have seen high quality carbon fiber bicycles that cost well over $10,000.00 US. They were chain drive. I can't afford them, but a bike as light as they are would be great for a serious pedal biker or racer. I think the most I have paid for a bike I intended to motorize is $200.00 and the most I have charged for a gasoline engined motored bike I've sold is $1,200.00. I am asking $1,700.00 for an e-bike I'm selling, because I have about that much invested in it.
  5. HeadSmess

    HeadSmess Well-Known Member

    yay :)

    yep, ive seen a porsche frame for $12000(just the frame), so $2500 is a mere drop in the pond...if youre a lawyer charging about $300 an hour...

    i know sand destroys chains too. its why i get rid of all the lube. i always say grit and oil is grinding paste :) ive always done it, except on o-ring motorbike chains...which ARE NOT 98% efficient. far from it actually. but when you have 70+ horsies, a little bit of loss doesnt matter(but wow, doesnt plain chain make a difference when you try it out!). same with the harleys and timing belts. you have that much grunt that losing a bit on the transfer doesnt matter at all. and then the stretching and smoothness factor works in the belts advantage.

    and of course, even a printer uses a toothed belt instead of chain. at that size, belt is waaaaay cheaper. small pitch chain is ****ed expensive, and printers...well, who wants to be tensioning a chain all the time, lol? and who cares about efficiency as long as the thing prints?

    a belt though, no matter how thin, narrow or hi tech it is, will always suffer from "bending friction", which is where all that lost energy goes :( flat/toothed belts admittedly are a lot better than the old v-belts.

    this is most likely why this bike im ranting about had a rear sprocket about 5 inches across... keep the bending to a minimum. and as for the "chain"ring...almost as big as the cranks!

    when it comes to the limited power available with pedals though, all i can think is "bling". along with the pricetag (i agree, price has NOTHING to do with the belt drive)... i personally hate bling :) and the guy in the bike shop :jester:

    buuut, most of all, i reallly hate trying to track down a hard to find/expensive part, because it wasnt standard and no longer manufactured, and noone stocks it!

    and yes, ive come across certain machines that should be using belts! do you know how much rs11 chain costs per 500mm? mainly because its only available in stainless. ties into that last paragraph... we were replacing it because it snapped. at the master link. because it ran both ways. a belt would have beeen ideal, but noooo, better to use a ridiculously small and expensive chain! in built obselescence annoys me too :jester:
    Last edited: Feb 2, 2012
  6. HeadSmess

    HeadSmess Well-Known Member


    ok, thats it! time to do something with all these frames i have! lol
  7. Yes, $1,200.00. Bike; around $200.00, RS EHO35 engine; $200.00, Staton chain drive system; a bit over $500.00(I think), high quality front wheel; $50.00, Cloud 9 seat; $35.00, BB-7 disc brake + caliper; $80.00, polycarbonate fenders; $35.00, high rise handlebars; $27.00, 1/2 gallon fuel tank; $18.00, 2 Armadillo hemisphere Kevlar cord tires; $88.00, miscellaneous stuff like lights, cable lock, etc; around $65.00. I don't like doing math, but I think that comes to over $1,300.00 in material alone. I don't count my labor, or the taxes, or shipping I paid on all that stuff, selling a 1 year old used bike, but the buyer got a great deal for a flawless, dead reliable bike with less than 2,000 miles on it and all the bugs worked out that delivered over 160 mpg and topped out at a little over 32mph.
    Last edited: Feb 2, 2012
  8. professor

    professor Active Member

    I love old fashoned "V" belts and am using them on primary drives as a clutch. Simple, obtainable anywhere and cheap, super long life too. Chains have been a real pain to me, needing spring loaded idlers, perfect alignment and of course lube.

    If I ever did another bike, I would go with the v belt around a rim attached to the rear rim, like the bikes of a hundred years ago. Would just have to have a removable rear triangle section for belt attachement.
  9. loquin

    loquin Active Member

    The toothed synchronous drive belts are very nearly as efficient as a chain. They are quiet, and are very low maintenance, and can be driven with a smaller sprocket (with a higher rpm) than a 1/2 inch pitch chain. Which can eliminate a gear or two in a gearbox. Gebe's are driven directly at 8000 RPM - i.e. - no gearbox at all.

    The net total efficiency is about the same or even a bit higher than a gearbox/chain combination.

    And, since a belt can stretch a bit under a shock, they may act a bit like a shock absorber in the drive train, and thus be a bit easier on other drive components.

    On the down side, belt/sprocket pulleys may be more expensive than good old roller chain/sprockets and a gearbox. And, as others have mentioned, sand being pinched in a pulley can wear out a belt pretty fast.
    Last edited: Feb 3, 2012
  10. curtisfox

    curtisfox Member

    If you mount the pully up high under the seat like a Wizzer you don't have to a removeable section. The belt goes between the frame tubes then.......Curt
  11. Jax Rhapsody

    Jax Rhapsody Member

    Well, tberes always shaftt drive
  12. when I built up my engine and I was going 35 miles an hour round my city. I thought my bike was the **** and was the fastest thing around . when I went to grange raceway and I could finally compare myself to other motor bikers I realized my bike really wasn't that fast. The other guys were going 40-50 miles an hour plus on a motorized bicycle. they were running both chain and belts. The point is that at the speeds u and I are traveling on these contraptions it won't matter what you choose. Either will work fine to transfer power to your rear wheel.

    I use a belt drive. That belt is now one of the last things I need to worry about failing on me when I ride. I worry about flats ect. If my belt snaps I already have a spare tied off . It would take longer to cut the zipties to free my spare belt than it would to reinstall the spare. I would need extreme bad luck for my spare to also snap on the ride. You can't carry a spare chain and if you did in yer backpack you need to take off your back wheel to change it. If your chain snaps you better watch out something is going to be destroyed.

    I have used chain and I had to carry lube. There risk of mess or spray with that. It was noisey and always seemed to seize/stretch on me over time. I had to worry about my chain on the ride. Your engine will fire up. You will twist throttle. The engine will turn and either the belt or chain will effectively transfer the power to the rear wheel.

    Choose the drive system and seal yer fate

    Time to pick up some wing stop.
  13. Cavi Mike

    Cavi Mike Member

    Because they reduce drive-train shock/vibration when not running expensive cush-drive rear wheels but mainly because they are cheap.

    Once again, because they are cheap. Chains are "life-of-engine" parts(meaning they won't need to be replaced before the engine itself) and are very expensive. An easy way to reduce the price of a car not just for supply costs but also production costs is to use a belt. Expensive cars use chains.

    That's because belts(v-belts) stretch and slip, not because they are strong.

    A belt on a bicycle really is a gimmick. The pluses don't amount to anything compared to the negatives which is why they're only on expensive bikes because, oddly, people with lots of money are pretty stupid when it comes to the real world.
    Last edited: Feb 5, 2012
  14. Cavi Mike, you are just wrong. I've replaced plenty of what you call "life-of-engine" timing chains in auto and truck engines over the years. Gilmer belts are no gimmick. They work very very well. Harley claims they will outlast a chain drive on a powerful, high torque motorcycle. I don't know if I quite believe that, but they do last a very long time. I know I had to replace the worn out drive chain on a Honda motorcycle I owned and it had recieved excellent care and maintenence.

    Geared belts are no gimmick, they are simply a good alternative to chain. One huge advantage they have over chain is light weight. With auto manufacturers trying to build as light as possible to improve efficiency/gas mileage, as well as a slight price advantage, they are here to stay until an even better replacement comes along. The GEBE motored bike drive system is efficient, smoother and quieter than chain, and light in weight. The new gilmer geared belts DO NOT slip or streach.
  15. Cavi Mike

    Cavi Mike Member

    I didn't say chains were infallible. You do know engines roll off the line and fail before they get shipped out the door, right? So should I say engines are also junk?

    Another thing, you're really truly honestly going to tell me you've done more chain replacements than belt replacements? I don't think so. Belts have a service life, that's why it says in clear letters right under the hood to change the bloody thing every 60k miles(give or take).

    As I said, chains are life-of-engine parts. Sometimes engines fail sooner than expected, sometimes chains fail sooner than they are expected but that's got nothing to do with the design, that's what's called "manufacturing defects" aka someone ran something out of tolerance and it got out the door.
  16. "Chains...... are very expensive". No they are not. They are slightly more expensive than belts, but hardly very expensive. "Expensive cars use chains." No, not all, the 3 Liter Ferrari V12 I helped rebuild used a series of gears up each cylinder bank to drive the overhead cams. BMW now uses belts in their newest engines, as do Jaguar, Acura, etc, etc.

    Someone mentioned shaft drive earlier in this thread and it is indeed a fine drive system, as I discovered on my BMW RS60. It is also very expensive as the bevel gears at each end are costly and fairly difficult to machine and is relatively heavy, compared to chain and belt drive systems.

    Geared belts will never replace chains completely, chains still have many valid uses. I never said belts will outlast chains, in fact I believe I conceded that chains will generally outlast belts. For us old codgers, a bike too heavy to lift, say over railroad tracks or up a flight of stairs, is a serious problem. The light weight, ease of maintenance, lack of stretch, smoothness, efficiency, and quiet operation of a gilmer belt drive are all pluses. The relatively shorter life of a belt compared to a chain is something I can comfortably live with. By all means, if you wish to stick with chain drive, be my guest. Just don't try to push your prejudices against the geared belts onto others, we know better.
    Last edited: Feb 5, 2012
  17. Max-M

    Max-M Member

    Reading all of this "Chain versus Belt" info has got me thinking. I've got a 4-stroke 49cc Hua Sheng F142 on my bike, with a Q-Matic drive. The Q-Matic has a 10-tooth sprocket attached to its centrifugal clutch, and the chain runs from there to a 56-tooth sprocket mounted on a hub adapter.

    I've had pretty good luck with chains, but I'm getting intrigued with the idea of a final drive belt. I'm wondering if it's feasible to somehow replace that 10-tooth clutch sprocket with a pulley, and the 56-tooth sprocket with a pulley that approximates the big sprocket's 9-inch diameter. An appropriate belt tensioner could easily replace my current stock chain tensioner.

    Has anybody had any experience with this kind of setup, or any ideas about it?

    PS: When does a member of this forum advance from "MBc Newbie" to one of the higher member levels...just curious.
    Last edited: Feb 6, 2012