seriously..why

Why not?

Belt drive is lighter I’ve been running the same belt and cigs through loads of shit for a long time it sheds mud better, it makes you look cool, chicks will dig it, and besides who likes being boring

seriously..why

Fair question.
I will try to answer it after I have ridden the thing with a belt..

Why?

Silence is golden, that’s why.

Is a well lubed singlespeed drivetrain with good chain line really that noisy?

Ringo – is it really lighter? Whenever I’ve looked at combo of belt, sprocket, chainring and weight from splitting the frame it’s a wash at best…

bencooper – that’s good to know, closest I’ve seen in the past was ford rosso red!

I should point out that I wasn’t bored enough to go to Halfords and test paint – it was just a random can I had on the shelf 😉

Sam
Is a well lubed singlespeed drivetrain with good chain line really that noisy?

Ringo – is it really lighter? Whenever I’ve looked at combo of belt, sprocket, chainring and weight from splitting the frame it’s a wash at best…

A good chain singlespeed is quiet – until you ride a good belt drive.

I’ve weighed the bits that came off

and the bits that went on

The weight saved is over 200gms. The split shouldn’t add more than a few grammes if it is done properly, eg a pin joint.

On One cog, steel chainring (afaics), and cheap shimano (?… solid pins and plates anyhow) chain, of course it’s heavier!

Those are the parts I was using.

I don’t get much life out of alloy chainrings so I don’t use them.

Sam, I’ve had a look in my shed for SS lightweight chain components – it appears to be the one place I don’t go weight weenie.

Any chance you could post up comparative weights for a chain, ring and cog using lightweight parts?

I bet that’s one of those extra-heavy, super-absorbent paper towels you have placed on the scales as well!

Weight weenie that I am, I zeroed the scales to allow for its weight. 🙂

Can’t be bothered actually weighing, but roughly
KMC X9 SL chain 250g
MRP podium ring 40g
Niner Al cog 20g

So 310g – not such a big difference and I’ve found all these components pretty durable.

They are some pretty fancy looking belt drive bits – what are they?

The front and rear cogs and the belt.

No shít? I’d never have guessed 🙂

The thread still lives.
Well i am still in germany.
Just got back from a very cold and wet few hours of skiing.
Belt bits above look like the standard cdx gates stuff.
I had a shorter belt waiting for me here, as well as a crude looking tension tool.
Bike test later this week with a bit of luck.

Just got back on my Peregrine after slogging through deep mud along the banks of the River Ouse and then zipping through the country lanes when I got sick of it. It is a mud muncher and a tarmac blaster. Fun belt or chain and a good way to enjoy a sneaky day off work!

I downloaded the free gates tensioning app, which picks up vibrations to determine tension.

I looked for this on Play Store and couldn’t find anything.
There’s nothing from Gates.
There’s one from Contitech, but it wants me to input a specific model of Contitech belt, so it’s not ideal for Gates.
Is it not available on Android ?
is there anything else I could use ?

Quick update.
Shorter belt just fits.
But on inspection the belt chainwheel needs some fiing of the shoulders to fit happily in the middle position.
Th belt chainwheel obviously wants to sit on the outside position, but this would screw the chainline.
A job for when i get to my dads garage.

Graham,
Do you know anyone with an iphone ?
I have the gates tensioner here, but would be expensive to post it to you..

Info here on a possible diy tensioner
http://bicycles.stackexchange.com/questions/5187/how-to-measure-the-correct-belt-drive-tension

Jerome
…the belt chainwheel needs some fiing of the shoulders to fit happily in the middle position.
The belt chainwheel obviously wants to sit on the outside position, but this would screw the chainline.

That’s the problem that stopped me with my Peregrine.

Don’t forget you can get some lateral adjustment by using a few shims under the shoulder of your BB.

If you currently have a chain on the bike, I suggest you measure how much lateral flex you can get out of the chainstay to ensure you allow enough clearance for belt drive ring.

The killer is that the widest position of the rear cog limits how far out you can have your front ring.

I’m hoping you succeed with this – it’ll make a good bike even gooder 🙂

Is there anyway you can move the cog outboard on the Alfine?

When I had mine (also on a Peregrine) I reversed the sprocket which has a 2.5mm offset, so giving a chainline of 47.5mm, rather than 2.5mm.

I’ve had a similar problem on my A with the Gates cogs. I had to have the front mounted far enough outboard to clear the chainstay, which meant having the rear cog mounted right on the end of my freehub. Its not helped by the assymetric design of the Carbon drive cogs. I checked with Gates and they can be reverse mounted if it would help you, although certainly on the front cogs, the teeth have more hardening treatment on one side, not the other.

Centretrack stuff is both less asymmetric, and can cope with misalignment and flex much better.

Thanks for your thoughts guys.
The chainline is close with the belt wheel in middle position, so all should be good hopefully.
Epicyclo – i will assemble with a couple of washers between shoulders and chainset and see how that looks before i file the shoulders down.
I am left with a 118t belt and a 25t cog here, so options for something else if this works.
J.

I had another look at the Contitech Android app and it is OK for what I want after all. You can just ignore the input boxes and go straight to the Start button.
Using the figures here, and classing myself as “Big and Powerful” rather than a “Lightweight Speedster” 😀 ,I’ve set the tension to about 80Hz. It’s hard to get an exact setting with an EBB.

Regarding the alignment problem;
An EBB makes this easier, as I can slide it side to side in the frame.
The CentreTrack kit comes with 1mm BB cup shims for fine tuning the alignment.
Could you put a shim on the right as epicyclo suggests, or move one of the spacers from the left to the right to get some clearance Jerome ? As long as your left crank and shoe miss the stays, moving the whole assembly across should help.

Peregrine has an EBB so as mentioned will allow me to fine tune chainline.
Issue I have currently is actually getting the ring to sit square on the crank arms rather, hence the suggestion of filing.

Quick update for anyone interested.
Few washers on the chainset and belt ring sat fine in middle position.
Chainline looks great.
First test was fine, other than the belt tries to walk sideways off the front ring under heavy tension.
Not entirely surprising as chainset I am using is slightly bent.
I have flipped the belt as suggested elsewhere and need to test again.
Otherwise will have to go from another chainset I have.
So positive ish, but a bit of a faff.
Sounded nice and quiet though..

Jerome – Member
…other than the belt tries to walk sideways off the front ring under heavy tension…

That can happen if the chainstay is flexing laterally. (Not a flaw, part of what gives the ‘feel’ of a steel frame)

You can try slightly offseting the front pulley to cause the belt to run against the flange. Or increse the tension.

Or get a centretrack….

+1

Centertack probably is the solution to keeping the belt in line.