Synchronous timing belts [SRO]

Which belts do y’all prefer?

I’ve seen this before…

But generally I just order the correct size from

Does anyone know which HTD5M belts actually work better for esk8?


For all you aussies and uk guys and girls these things are great. Continental like the tyres lol.
They last ages and if you break one before 4 they will send you a new one the next day providing you pay for it. :smiley: No but seriously I have been running these for 8 months and they are without a doubt the longest lasting belts I have used thus. Bit pricey but if you are not changing them for twice as long then they are cheap by comparison. Hard to get in the us apparently though so suck shit america. :laughing:
You have no idea with all your easily obtained lovely esk8 bits how long I’ve waited to say that. I’m stuck out here in the colonies but I can get belts.
Ah shit.
Thats all I can get easily.
Still counts.


Been running those cheap aliexpress PowGee belts (and similar chinese no name belts) since I started esk8ing and so far (jinx…!) never had a belt snap on me.


Does anybody remember this thread where it explains how to calculate belt length, I cant seem to find it. Also what’s the best material to use. Thx

1 Like



Thx, got it. I couldn’t find it. I thought it was called CB something… thx again

I think the real question is which of the belts on the chart stretch and which don’t stretch?


Initially I had brought up steel as an alternative to kevlar when I stumbled across them on ebay, thinking that because aramid does poorly in abrasion, that at the radii our belts travel the steel would be less prone to snapping, but B264, actually paying attention to the chart, pointed out glass having the best characteristics overall.

I don’t have enough experience to make a call, so watching this topic for anyone that does.

1 Like

All belts stretch is my experiance bud, I have never snapped one but stretched them all

1 Like

Do you replace them once stretching starts/it starts skipping?

Timing belts, by their nature shouldn’t be stretching… think of your car’s interference engine, the valves and pistons don’t like each other enough to try to share the same space at the same time…

None of them stretch. They break or don’t break, but don’t stretch. Not even while breaking.


That may be your experiance, but it’s not mine. When you every so often have to adjust your motors on their mounts outwards slightly you know they have stretched, no other explanation

The other explanation is that your motor mounts have been moving.


My motor mount isnt moving

Believe it or not you will get your highest efficiency running a belt at 80% of it’s breaking strength. The reason is the belt does elongate a tiny amount under load. That minuscule elongation helps align the teeth and gets more teeth working for you. Fiberglass will give you the best efficiency.


Something else to consider in this lovely debate that has been going on for as long as I have been frequenting these forums is idlers. Idlers wear the belt from the top so instead of just teeth wearing out the belt effectively gets thinner over time and this does cause them to stretch. Trust me on this. I have even gone so far as to mark my motor positions to check the integrity and without movement the belts over time will start to skip more on hard braking. No other explanation but stretchy wetchy.

Lee get some contitech in your life. Rs. Accept no substitute. As good as a fresh pair of Gazelles.


There is an easy way to check this out, if I buy a brand new belt from the same manufacturer and cut it, measure it and do the same to the old one we can see. I use “cheap” belts without idlers, they are fine for a while then start to skip so I bring the motors out a touch then they are fine again for a bit and start to skip. I dont think the motors are moving, the bolts are always tight

1 Like

You are preaching to the converted mate. Belts stretch and I don’t care what Brian says on the matter. I have owned 5 harleys in my lifetime and at 50000 miles you need to change the drive belt. Reason? They stretch. From the horses(Harley mechanic) mouth. Why do you think that at various service intervals you get a massive hit? All the belts need changing. Really don’t want to spark off this debate again though so I am going to respectfully fuck off now before Brian comes in all hot and bothered.

1 Like

Lol. Brian has opinions, like all of us I suppose just his are harder to change than most. I will still do the experiment I think but it wont be until after summer as my street board is now in Spain until August (dont ask) and I am in the UK.

I’m happy to be proved wrong on this but yeah, cars timing belts stretch and they are a huge force (crank) driving a small load (cam) our setup is a small force (motor) driving a large load (me being a fat bastard)


Its a question of how much they stretch that has people confused. They have a minimal torsional flexibility. They are designed to be very resilient to stretch. Not rocket science to work out that those properties will decrease as the belt becomes worn or thinner. I have definitely noticed it more since I started using idlers. All my comments on how things work are not based on science to be clear, they are based on what I experience on a day to day basis reliant on my own riding style and physiology. I have powerful stuff and am heavy and ride like I stole the things. Its one of those topics that is so debated with so many variables that is almost impossible to prove.
My belts stretch. His might not. Yours might but Joe Bloggs down the street might be fine etc etc etc. Its what makes this place fun though.

1 Like