Belt drive to chain? Help.

Okay, so I've bought a trek district belt drive and I like it..a lot. The problem is the belt tension has to be so high to stop it skipping it actually puts resistance into drive train. For example, if I pedal the bike with the wheels off the ground backwards....it actually spins the wheel. I don't think this will be good for the bottom bracket long term.

So once the belt wears out or I get fed up of the extreme tension required, I'll want to change to chain and go fixed. It is however, 135mm rear spacing - what's the easiest way to sort this? Is it as easy as building up a rear wheel or is the chain line likely to be wonky due to the weird rear hub that's currently on there. It looks like a shimano splined freehub but it's very very short, like it'll take only a sprocket or two.

Anyone done this or know about trek district rear belt drive hubs?

Cheers in advance.

Is the belt slipping or skipping? I thought that the belts were toothed and the drive is held by the 'teeth' not as a ribbed belt.

For example, if I pedal the bike with the wheels off the ground backwards....it actually spins the wheel. I don't think this will be good for the bottom bracket long term.

Don't get what you mean by this? You lift the back end of the bike off the ground, turn the cranks backwards and the freewheel equipped rear wheel rotates backwards with the cranks? Would that be affected by chain/belt tension?

Is the belt slipping or skipping? I thought that the belts were toothed and the drive is held by the 'teeth' not as a ribbed belt.

It is but they still skip if the tension isn't high enough.

Don't get what you mean by this? You lift the back end of the bike off the ground, turn the cranks backwards and the freewheel equipped rear wheel rotates backwards with the cranks? Would that be affected by chain/belt tension?

Friction caused by the tension putting pressure onto the freehub bearings.

Something isn't right IMO as that seems like alot of tension.

http://www.carbondrivesystems.com/~/media/CDS/TechPDFs/Gates-Carbon-Drive-Tension-Recommendations.ashx

This from gates may help.

Something isn't right IMO as that seems like alot of tension.

http://www.carbondrivesystems.com/~/media/CDS/TechPDFs/Gates-Carbon-Drive-Tension-Recommendations.ashx

This from gates may help.

Well known issue, that's what they changed the design to CDX. I use the ipad tension app.

How old is the belt?

300 miles, why?

Suspect something is worn.

Why do think that? The bike has done 300 miles from new and the belt, sprocket and front ring is in perfect condition. Gates have acknowledged it is a well known issue and as such even changed the whole design of their cycle belt drive system from CDC to CDX - resulting in far less tension being needed for zero skipping.

The bottom bracket is in good order and the freehub spins freely when the belt is disconnected.

FYI I've found a supplier of 130mm fixed wheel set for £90 here....

http://singlespeedcomponents.co.uk/wheels/700c-carthorse-black.html

With sealed bearing no less. I just need to check the belt/chain line before ordering.

Thanks for the replies though.

it's a common problem with belt drives, especially earlier models. We've seen hubs wear prematurely on districts because of the tension required, i think trek eventually went back to using chains

it's a common problem with belt drives, especially earlier models. We've seen hubs wear prematurely on districts because of the tension required, i think trek eventually went back to using chains

I do like the idea of the belt and it is great not having to oil a chain and it is soooo quiet.

Is it just a case of banging a 130mm (with spacers) wheel and replacing the front belt ring with a chain ring? Or is a case of messing about?

I do like the idea of the belt and it is great not having to oil a chain and it is soooo quiet.

Is it just a case of banging a 130mm (with spacers) wheel and replacing the front belt ring with a chain ring? Or is a case of messing about?

135mm is standard OLD for MTB hubs, no? Can you just build a wheel around one of those? Alternatively, use a velosolo bolt-on cog on a disc-brake hub.

Apparently, (and I'm going to measure to be sure) trek decided on 132.5mm rear spacing to give flexibility in hub options. So rather than stretch the alloy frame I'm planning on using 130mm and spacers. 130mm fixed wheels seem readily available, where as 135mm seems to be hubs supplied only. Where does 130mm come from? Hybrids?

7-speed mtb and 8, 9 & 10-speed road hubs are 130mm (Sheldon is your friend).

Apparently, (and I'm going to measure to be sure) trek decided on 132.5mm rear spacing to give flexibility in hub options. So rather than stretch the alloy frame I'm planning on using 130mm and spacers. 130mm fixed wheels seem readily available, where as 135mm seems to be hubs supplied only. Where does 130mm come from? Hybrids?

Alloy or alu?

Alloy or alu?

My bad alu.

It'll be fine with 130 or 135.

The hub on the grey/orange District is (or at least was when I worked in a Trek stealership/owned a District) a cassette hub.

The Gates cog and free hub body are both standard Shimano 9spline pattern so singlespeed cogs are readily available.

The free hub is narrow as befits the singlespeed set up but actually wide enough to run a couple of cogs a la dingle speed, otherwise the only oddity is that it uses a male thread on the free hub and a female threaded lockring. The lockring is interchangeable with a bottom bracket lockring by the way.

I changed my own District from belt to chain so if you have any other questions I may be able to help.

Perhaps also worth mentioning though that while I had issues with the drivetrain I never had this issue. The hub and free hub use readily and cheaply available cartridge bearings though and given that you can get un5x BBs from crc for under a tenner I reckon you could have several bearing complete bearing changes for the cost of swapping to chain drive.

Cheers guys, it's all moot as I just can't get over my irrational fear of carbon fibre. I didn't realise till I'd handed over my money it had carbon forks. I thought I could handle the fear, I can't so now it's on the bay.

wtf?

I have carbon fibre forks on my fatbike (and my fixed, my road bike and the commuting bike), never given me any concern. even my 29er has a carbon steerer and fork crown.

Isn't this usually where someone is supposed to post the Niner fork video?

Niner Bikes Fork Hammering - YouTube

I had a £5k Scott Genius Ltd snap on me and knocked me unconscious, fractured my eye socket and buggered my wrists for months.

It was a manufacturing fault that could only be detected by x ray...so yeah I feel justified and can't get over it.