[Hog Head]

I am trying to decide if there is any demand for a 2.666 stock gear ratio in the Super Meteor belt dive conversion kit
The Interceptor belt drive conversion kit is available in either 2.5 or 2.375:1
Pic is 2.375:1

650 Meteor rear sprockets are available in 38, 40 (stock) and 42T , with front sprockets at 15 (stock) and 16T

Stock Meteor gearing is 15/40 = 2.666:1 Clearly the factory Engineers have geared the bike more as a cruiser , and while great for slower cruising and acceleration; it seems to me at least, is a bit low geared for higher speeds.

Using the optional 38T rear sprocket with the stock 15T front = 2.53:1 finial drive ratio, and the same as the stock Interceptor - a good compromise all round gear.
The "16T mod" on a Meteor using the stock 40T rear sprocket = 2.5:1 so very close to the Interceptor stock gearing, and one of the currently available belt drive ratios

A 16/38 sprocket combo = 2.375 and what I run for higher speed to keep up with my mates without flogging it to death. A bit trickier on take off and creeping forward in 1st, but a better fit to my riding style

Does anyone find the stock 650 Meteor gearing a bit low, and if so what ratio would you prefer?
Poll above

[MMRanch]

I'll put the 16 tooth sprocket on after the first oil change.

[expatbrit]

i only wish 6th was a bit taller. Belt maybe...

[MMRanch]

If I was going belt the 2.375 would be the one I'd go with .   
Yes the stock gearing might be alright for those folks who live in town ... but ... out here in rural America I need long legs to run too and from town.

I'm still in the brake-in area , but if I wanted to go for a belt when the original chain is gone ... how pricy is it to do such a thing ? 
 

[Hog Head]

If I was going belt the 2.375 would be the one I'd go with .   
Yes the stock gearing might be alright for those folks who live in town ... but ... out here in rural America I need long legs to run too and from town.

I'm still in the brake-in area , but if I wanted to go for a belt when the original chain is gone ... how pricy is it to do such a thing ? 
 

https://rstech.my-online.store/product/royal-enfield-650-belt-drive

Test fitting to a 650 SM over the holidays

[MMRanch]

Well HH

I'm thinking the front pully worked just fine and the rear pully had one too many holes in it ?

I'll be working on wearing out the original chain and sprockets while you work on my belt replacement.   Those longer legs will be the ones I'll want.
There isn't any hurry on my part .    It will be about the middle of the summer before I need them .   
But
Being how we are just now getting the Super Meteor ... I'm thinking most of us ex-Harley riders that have seen the light to a lighter way of thinking (and ridding) will be looking for a Belt Drive set-up.

 

Before the Harleys I also had a couple of Suzuki Savage/S-40 bikes with belt drive's .   
That Belt is a wonderful thing !
I had a couple of Moto Guzzis also and tried the shaft drive way too. 
But
I've liked the Belt better than the other two ways.

[Hog Head]

Note that the 16T front sprocket ratio is not the same on the SM and Inter/Conti due to stock rear sprocket size, and tyre size.

A SM 650 with a 16T front sprocket (2.5:1) is virtually the same finial drive ratio as a stock Interceptor/Conti 650 (2.53:1)
Tyre height is 25.4" for the SM vs 25.2" for the Inter/Conti, so a difference there. 
This ratio calculation is a bit simplistic as it does not account for the PCD difference in sprocket vs pulley, and with the tyre difference is is very close to the same.

The SM is a fair bit heavier at 241 Kg vs 218/198 Kg - presumably the Inter/Conti difference is the centre stand.  With a heavier bike, a heavier rider, and hilly terrain, the limited torque becomes an issue in pulling a higher gear.
My Interceptor has tubeless tyres, no centre stand, lithium battery, and a TEC 2"1 pipe so a bit lighter than the Conti 650, and works well with a 16T mod at  2.375:1

My thought is that a "16T mod" on the SM would be a good all round gear ratio, given the taller rear tyre and heavier weight.
Any higher finial drive ratio (numerically lower), may be a bit high for a heavier rider in hilly terrain - No data nor experience to back this up, hence the poll.

With only 2 replies to the poll I am proceeding to fit a set of 2.5:1 pullies (SM x 16T mod) Jan 28 and see how it rides

[MMRanch]

Your on to something with the SM weight.
I've got the 16 tooth F now and the gearing seems about right . 

[Morgan65]

My personal opinion is the Super Meteor 650 gearing is spot on. Even with the wife on the back it’s perfect.  I wouldn’t change a thing.  If one was going to pull a trailer or run a sidecar then maybe I’d change it up. 

But if you would come up with a well engineered belt-drive system I would buy one and I bet they would sell a lot of them. 

[Hog Head]

Thanks for the feedback.  I have been working on this a bit more and now completed a small run of belt drives for the SM.
These are currently in the queue for hard anodizing on the rear pulley, and heat treating + plating on the high tensile steel front pulley.

Gearing is a bit confusing with a larger number being "lower" geared – IE the SM 650 stock sprocket ratio at 2.6:1 is lower than the SM rear 38T or 16 front mod at 2.5 

Noteworthy that this model does not have a tach...............Using the stock gearing, 120-140 kph (75 - 87 mph) calculates to 5170 - 6050 rpm, not accounting for the bike weight, your weight, rolling resistance, or drag from panniers or a windscreen  - measured rpm will be higher than this calculated engine speed.  5170-6050 rpm is past the engine torque peak, and pushing the long term piston speed into the rule of thumb range for a shortened life span.

Torque gets you there, and HP keeps you going.  Carrol Shelby famously said “horsepower sells cars, and torque wins races”.  RE Street riding is mainly in the engine torque band, and I try to match gearing to my riding style.  Having a cruising rpm in 6th in the meat of the torque band, while not flogging the engine, works best for me. 

The Enfield 650 engine has modest torque and horsepower, so gearing becomes a compromise between acceptable performance, the ability to pull a higher gear,  and ones tolerance for wringing its neck to keep up with motorway speeds in some countries (or in my case spirited riding mates and no law enforcement).  A horses for courses situation.

Feedback to date over several platforms, favours the higher gearing