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Cant really understand why people are negative towards belts, anything new I suppose.
it it just scepticism ? We know chains work about adequately in MTB conditions - there are still questions about increased bearing sideloads and mud/stone resilience with a belt.
OK, I'm reading this with interest. So you need a modified frame; you have to settle for either single speed or go for an expensive hub gear system with a limited range; you can't use it on a full suspension frame; and when it wears out (which it will) it costs £250 to replace.
I've heard about a system that works on all frames, hard tail and full suspension; is cheap to replace and parts are readily available; and it accomodates an absolutely massive range of gear ratios - as many as you will ever need. It was invented in the 19th century and apart from various fine tuning and development, ramains largely unchanged since the 1930s.
It's called the 'chain and deurallieur'.
Wayyyyy different I guess but I had a Strida folding bike with a belt - supposedly good for 60,000+ miles. I think my first one lasted about 200 miles before snapping. And that was on a gentle commute from the office to London Bridge station...
Ooh that's nice. If they did a 29er I'd seriously consider buying one.
Regarding the 60k cam belt change. That's 60000 miles at an average of what, 30mph at 5000rpm ? How many revolutions is that ? Probably more than you'll ever pedal in your lifetime. And cam chains run in an oil bath anyway.
A more realistic comparison would be the belt drives used on Harley Davidsons. They've been around a few years and have proved reliable.
There's an interesting discussion on belt drive Rohloffs on the Thorn forum.
http://www.thorncycles.co.uk/forums/index.php?topic=2266.0
MilitantGraham - Member
A more realistic comparison would be the belt drives used on Harley Davidsons. They've been around a few years and have proved reliable.
It would if people rode Harley Davidsons through axle-deep mud, without mudguards etc. Harleys are built mostly for the US market where grit, mud and rain aren't so much of a problem. Motorcycles that are built for more demanding climes are usually chain-driven.
Quiver = windsurfing schpeak...
And surfing...
Cool looking bike in your "stable!"
Good point, Shibboleth, I suppose an even more realistic comparison would be motocross bikes, but as there are no belt drive MX bikes, as far as I know, we can't make that comparison.
I guess I'll have to let Rip and other pioneers gain some long term experience before I commit to buying a new frame and £250 worth of belt and pulleys.
As far as new technologies, or established technologies in new applications, go though, it's looking pretty good so far.
Shibboleth - Member
...It would if people rode Harley Davidsons through axle-deep mud...
I used to, and that's why I am convinced belt drive is good.
Chains and derailleurs are fine for their purpose.
But there are people who run single speed or hub gears, and belt drive is superior for that purpose.
BTW the Strida uses a different belt AFAIK
Epicyclo
Gates say to allow up to 2mm for tensioning. I'm using 0.5mm and finding it adequate and a similar to a SS chain. I suspect you would need the whole 2mm if you had a bike with laterally flexy chainstays. Of the bikes I have converted, 2 were done with no provision for adjustment, and just with dropouts placed to provide the 0.5mm tension.
I think you may be overdoing the tension a bit there.
The Gates manual says:
[i]b. Checking tension by hand: Applying 5 lbs to 10 lbs of pressure on the center of the belt span, the belt should deflect about [b]1?2-inch[/b]. (For detailed tensioning instructions, please review the Tension_Requirements.PDF document)[/i]
...unless I'm misunderstanding the manual.
Rip - Member
Epicyclo ... I think you may be overdoing the tension a bit there.
Ah, I should have made it clear that I was talking about along the chainstay length, not the usual vertical at midpoint method.
MilitantGrahamOoh that's nice. If they did a 29er I'd seriously consider buying one.
They do! no excuses now 😉
Where did the £250 replacement come from? At VN a replacement belt is €60.
Gates quoted me £250 for two cogs and a belt.
ouch
Gates quoted me £250 for two cogs and a belt.
The thing is until we find out how long these last in the real world we won't know if that's expensive or a bargain.
That's very interesting, Nicknoxx, particularly given that on this MTBR thread you can see a Pro29 specced with a belt drive!
I suspect they didn't want to change the design as I only introduced the idea of a belt quite late on (see below)
How's your delivery coming along? I am having a Ridgeline 29 tweaked to take Rohloff neatly, adjusting cable guides and suchlike. Quoted 7-8 weeks, 15 weeks later and still no sign of a frame... uber-relaxed customer service, i.e. lacking in detail.
My first contact with Lynskey was in January it took until the end of May to get a final drawing with only three revisions (I'd supplied quite a detailed drawing initially) It's now in production. I told them right at the beginning that my 50th birthday was at the end of July and it had better be ready by then. Nice guys and quite helpful but they're too busy to communicate effectively in my opinion.
This is the drawing of my dropout
Lynskeys comment was:-
We will not be able to warrant this frame against any breakage on the dropout when adding the split drive-side bolted stay for carbon belt drive. Because of the design and size of the dropout, there will ultimately be too much torque and stress on the single weld specifically at the chain stay on the drive side. And with our experience an eccentric bb doesn’t allow enough adjustment to get the proper belt tension as specified by Gates Carbon – that is the reason for a slider style drop-out allowing 7.5 mm of tension adjustment.
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Rubber is uber tough, much less brittle than metal. It's much more elastic than metal so it wont lengthen. Should hold much less crep, needs no oiling and will clean easily. Also, you aren't shifting it so that in itself will improve reliability and reduce wear over a conventionally geared bike. Hopefully, changing belts will be very infrequent, perhaps 10,000+ miles.
Am very interested in your results of running it throughout next winter.
TheSwede - MemberGates quoted me £250 for two cogs and a belt.
They quoted me the same when i asked about converting the timing chain on our tandem.
They also said that it would only be good for "leisure" riding as the power from two people cranking hard on an offroad tandem would make the belt slip.
They also said that it would only be good for "leisure" riding as the power from two people cranking hard on an offroad tandem would make the belt slip.
Surely only the rider at the front puts any load on the timing chain/belt
Surely only the rider at the front puts any load on the timing chain/belt
I'm just repeating what they said.
Having looked at the way the stokers chainring gets worn on both sides of the teeth though I'd have to agree with them.
If you want to give me £250 to buy the bits with though I'll fit them and tell you what happens. 😉
Nicknoxx, I remember seeing an earlier picture of your frame design a few months ago; that really is a beautifully designed dropout. I hope that it is delivered and built on time for your 50th, a stunning present.