The spec for this can be viewed at https://www.ternbicycles.com/bikes/471/vektron-p7i
I got my bike from 'Bicycles by design' in Telford (OK, really in Coalport), since they were one of the few places that actually had a usable demonstrator, which I could try before parting with a 50% deposit. I bought two, since my partner thought she would like to ride along with me .. she has since decided she doesn't like cycling, so one rapidly went back to be sold via eBay.
The only deviation from the spec I have noted is that many of the videos show the RH (detachable) pedal can be clamped into the back of the (very uncomfortable) Tern seat, but this facility isn't there on my seat. Not a big issue, since the seat isn't there either - the bike now sports a Brooks 67, whicb is 1000% more comfortable already.
The bike folds fairly easily, and while heavy, I can lift it into the back of my X3 without too much trouble. Two fit fairly easily, with a sack of bubble wrap between them, and a tie down strap between the boot rail lashing points to keep them from braining the occupants if you crash stop. You do need the back seats down, although you can one in without doing so. Removing the RH pedal reduces the chances of damage, but it not actually required; dropping the seatpost probably is, unless you are so small it is already way down. Only wrinkle with folding it to make sure the steering is rotated just half a turn in the right direction, and unwound similarly afterwards - it is possible to wind the steering through about 720 degrees, which is bad for the cables and hoses. (And potentially lethal for the rider)'
The Shimano hydraulic disc brakes work a treat, and hardly squeal at all .. very impressive, no more V brakes for me! The 7 speed hub gears work as expected, but are sometimes slow to change down unless you really give them 'pedal free time' to get on with it. The shortest gear ratio is about 3m (road travel per pedal rev) which is really too high for comfort up the steepest local hills, even in turbo (or maybe I am just feeble). A good derailleur or (whisper it) Rohlhoff, would go down to ~2m or less. I personally would like lower gears .. maybe I am doing it wrong, but at my normal cadence I hit (an indicated) 20MPH without bothering the highest gears at all.
The motor is relatively quiet, but is at the puny end of the Bosch range. I live 1000 ft up in Shropshire, and even in first gear and Turbo, some of the hills are a challenge .. my round trip to the Post Office is 6 miles of riding the brakes there, and 8 miles of (mostly Turbo) back. Motor range seems to be 20-25 miles on the 400 WHr battery, although I have not actually run it right out yet - I go it down to saying '0 miles left' after 21 miles on a cold windy day, but it still had some juice left .. just as well, the hills with no power would be a walk-up job.
Top speed is not an issue - the local back roads have gravel traps (and grass) down the middle, swathes of gravel (and driftwood) at the bottom of the hills where the streams overflow, and potholes which have been growing since Cromwell was a lad .. scare the tractors in places. The bike copes OK with most of it, but the 'Big Apple' tyres (with Tannus inserts) running at about 2.0 bar (no front suspension!) don't inspire confidence on the slipery stuff.
The steering is best described as 'light' (I must be remembering part rusted headset bearings) or, less charitably, 'twitchy', when faced with poor surfaces.
This bike is really set up for commuter road, or sustrans routes. It has all the fittings you could reasonably want (bell, lights run from the main battery, lightweight ('flimsy') mudguards, chain guard, rack, kickstand, etc), although you need to add your own panniers, and mirror.
It is (the usual, for a folder) 'one size fits all', which is certainly true of the two stage telescopic seatpost. This has nearly half a meter of adjustment (48" inside leg anyone?) , but the handbars are less forgiving, with only about 6cm of extra height on tap, so at 6' 1", I find myself bent further forward than I really like. Tern tell me "Vektron P7i comes with a 320 mm Physis handlepost. The length can be upgraded to 350 mm.", but my LBS has yet to confirm and advise how many arms and legs that might cost, and an extra 30mm doesn't sound like a massive leap upwards.
The other gotcha I ran into was that there is nowhere to attach the holder for my purchased 'sold secure gold' Abus D-lock, most of the frame being non-cylindrical, and the folding mechanism scotching some of the options. So if someone wants a (seriously heavy and bulletproof, probably overkill for rural Shropshire) https://www.amazon.co.uk/gp/product/B00HN47M5C, for which I also purchased a spare 3rd Key, get in touch .. never used. D Locks are a bit of a faff to fit to small wheel folders anyway, I discover.
My only other gripe is that whoever designed the P7I (Hub Gear) model, being stuck with the Derailleur frame / dropouts, seems to have gone for the whole 'lets use the same chain and keep as much as we can' design approach, which (look at the pics!) results in a ground hugging chain tensioner. I'm not a bike engineer, but I am sure something simpler and less vulnerable should be possible, even with the 'wrong dropouts' type of frame. I have had the chain leap off the rear sprocket (and tensioner) and jam the rear wheel once already - presumably it collected up a bit of rubbish from recent hedge trimming, and 'De-railed'.
And despite the Tannus inserts I picked up my first puncture on the same outing - a thorn which would have served well as a 1950 gramophone needle (we used to use them sometimes) had gone straight thru tyre, tannus, and tube, and finding the pinhole at the roadside proved impossible, so I resorted to the 'walk home get the car' (not having the tools or technique to get the whole wheel off while sat in the hedge). The tyre selection for Big Apple replacement doesn't include Marathon Plus (or e-plus) models, unless you want studded winter tyres (and with no suspension except the balloon tyres the doesn't sounds great).
Overall - I'd give it 3.5 or 4.0 out of 5, if you need something you can stick IN the car and take to your favourite beauty spot for a ride. For lugging around London, probably a bit heavy, and for serious off roading, forget it. It also has a fairly low weight limit (105Kg iirc), so won't suit some folks, and it isn't a full up cargo carrier.
I foresee a tradeup somewhere down the road ..
I got my bike from 'Bicycles by design' in Telford (OK, really in Coalport), since they were one of the few places that actually had a usable demonstrator, which I could try before parting with a 50% deposit. I bought two, since my partner thought she would like to ride along with me .. she has since decided she doesn't like cycling, so one rapidly went back to be sold via eBay.
The only deviation from the spec I have noted is that many of the videos show the RH (detachable) pedal can be clamped into the back of the (very uncomfortable) Tern seat, but this facility isn't there on my seat. Not a big issue, since the seat isn't there either - the bike now sports a Brooks 67, whicb is 1000% more comfortable already.
The bike folds fairly easily, and while heavy, I can lift it into the back of my X3 without too much trouble. Two fit fairly easily, with a sack of bubble wrap between them, and a tie down strap between the boot rail lashing points to keep them from braining the occupants if you crash stop. You do need the back seats down, although you can one in without doing so. Removing the RH pedal reduces the chances of damage, but it not actually required; dropping the seatpost probably is, unless you are so small it is already way down. Only wrinkle with folding it to make sure the steering is rotated just half a turn in the right direction, and unwound similarly afterwards - it is possible to wind the steering through about 720 degrees, which is bad for the cables and hoses. (And potentially lethal for the rider)'
The Shimano hydraulic disc brakes work a treat, and hardly squeal at all .. very impressive, no more V brakes for me! The 7 speed hub gears work as expected, but are sometimes slow to change down unless you really give them 'pedal free time' to get on with it. The shortest gear ratio is about 3m (road travel per pedal rev) which is really too high for comfort up the steepest local hills, even in turbo (or maybe I am just feeble). A good derailleur or (whisper it) Rohlhoff, would go down to ~2m or less. I personally would like lower gears .. maybe I am doing it wrong, but at my normal cadence I hit (an indicated) 20MPH without bothering the highest gears at all.
The motor is relatively quiet, but is at the puny end of the Bosch range. I live 1000 ft up in Shropshire, and even in first gear and Turbo, some of the hills are a challenge .. my round trip to the Post Office is 6 miles of riding the brakes there, and 8 miles of (mostly Turbo) back. Motor range seems to be 20-25 miles on the 400 WHr battery, although I have not actually run it right out yet - I go it down to saying '0 miles left' after 21 miles on a cold windy day, but it still had some juice left .. just as well, the hills with no power would be a walk-up job.
Top speed is not an issue - the local back roads have gravel traps (and grass) down the middle, swathes of gravel (and driftwood) at the bottom of the hills where the streams overflow, and potholes which have been growing since Cromwell was a lad .. scare the tractors in places. The bike copes OK with most of it, but the 'Big Apple' tyres (with Tannus inserts) running at about 2.0 bar (no front suspension!) don't inspire confidence on the slipery stuff.
The steering is best described as 'light' (I must be remembering part rusted headset bearings) or, less charitably, 'twitchy', when faced with poor surfaces.
This bike is really set up for commuter road, or sustrans routes. It has all the fittings you could reasonably want (bell, lights run from the main battery, lightweight ('flimsy') mudguards, chain guard, rack, kickstand, etc), although you need to add your own panniers, and mirror.
It is (the usual, for a folder) 'one size fits all', which is certainly true of the two stage telescopic seatpost. This has nearly half a meter of adjustment (48" inside leg anyone?) , but the handbars are less forgiving, with only about 6cm of extra height on tap, so at 6' 1", I find myself bent further forward than I really like. Tern tell me "Vektron P7i comes with a 320 mm Physis handlepost. The length can be upgraded to 350 mm.", but my LBS has yet to confirm and advise how many arms and legs that might cost, and an extra 30mm doesn't sound like a massive leap upwards.
The other gotcha I ran into was that there is nowhere to attach the holder for my purchased 'sold secure gold' Abus D-lock, most of the frame being non-cylindrical, and the folding mechanism scotching some of the options. So if someone wants a (seriously heavy and bulletproof, probably overkill for rural Shropshire) https://www.amazon.co.uk/gp/product/B00HN47M5C, for which I also purchased a spare 3rd Key, get in touch .. never used. D Locks are a bit of a faff to fit to small wheel folders anyway, I discover.
My only other gripe is that whoever designed the P7I (Hub Gear) model, being stuck with the Derailleur frame / dropouts, seems to have gone for the whole 'lets use the same chain and keep as much as we can' design approach, which (look at the pics!) results in a ground hugging chain tensioner. I'm not a bike engineer, but I am sure something simpler and less vulnerable should be possible, even with the 'wrong dropouts' type of frame. I have had the chain leap off the rear sprocket (and tensioner) and jam the rear wheel once already - presumably it collected up a bit of rubbish from recent hedge trimming, and 'De-railed'.
And despite the Tannus inserts I picked up my first puncture on the same outing - a thorn which would have served well as a 1950 gramophone needle (we used to use them sometimes) had gone straight thru tyre, tannus, and tube, and finding the pinhole at the roadside proved impossible, so I resorted to the 'walk home get the car' (not having the tools or technique to get the whole wheel off while sat in the hedge). The tyre selection for Big Apple replacement doesn't include Marathon Plus (or e-plus) models, unless you want studded winter tyres (and with no suspension except the balloon tyres the doesn't sounds great).
Overall - I'd give it 3.5 or 4.0 out of 5, if you need something you can stick IN the car and take to your favourite beauty spot for a ride. For lugging around London, probably a bit heavy, and for serious off roading, forget it. It also has a fairly low weight limit (105Kg iirc), so won't suit some folks, and it isn't a full up cargo carrier.
I foresee a tradeup somewhere down the road ..
