Drive train changes....

[[XAP]Bob]

I'm pretty much through my initial pair of chains and cassette - it's skipping in the middle few gears, although I might try shortening the chain a bit...

So my options:
- Replace the 9-32 capreo cassette with another - £75 (from ICE)
- Replace with a 9-26 capreo cassette from a.n.other - £50
- Drop in another 20" wheel with a 7 speed IGH
- Drop in another 20" wheel with a 9 spd cassette (normal)
- Get an SA CS-RK3 (3 speed freehub) and a standard 9 speed cassette - £100 + £15 + £10 to build the wheel


Thoughts:
Straight replacement is obvious, however the cheaper option removes the lowest gears - and I'm going hilly later this year (Wild Wales Challenge).
The drop in wheels are also obvious, the 9spd should be a straight replacement, and will probably be my stopgap, but it doesn't have disk mounting, the 7 speed has a coaster brake, so a bit of random complexity in there.

The SA is the most expensive option in the short term, but it provides:
- Cheaper replacement cassettes in the future (by a long margin - they become cheaper than the chains!)
- Almost identical range to my current setup (just using the middle front ring)
- Higher/Lower gear ranges in 33% jumps (useful for Wales later in the year, stop at the top and bottom to change the front, or just use another shifter for the front gears)
- Change at the lights capacity (so I'm never stuck in completely the wrong gear when I stop)

Does anyone have any experience of the SA hub - or have a "spare" dual drive hub I could test ?


In virtually any case I'm going to have to get more chains pretty soon - and three chains is another cost in the mix.


http://www.bentrideronline.com/messageb ... hp?t=73212

[squeaker]

SA hub adds 1155g (minus weight of existing hub)! Not ideal on a suspended wheel? No experience of this type of SA hub, though, but would offer the opportunity of tidying up the front (single ring - also weight saving). Attaching the hub gear change cable anchorage to the swing arm might get messy.

EDIT: being silly with the last comment - I'd forgotten that the cable outer end is held in a bracket mounted on the axle (or it is on the 5-speed I have) - though 'cos of the shape of the rear axle dropout it would look a bit ungainly (compared with the rear mech cable run alongside the swing arm).

[[XAP]Bob]

I'd not considered the weight on a suspended wheel, but given that the rack is part suspended I'm not convinced that it's too bad an option - although adding a kilo to the trike might be a little ott.

I'm quite happy leaving the front of the trike alone at the moment (extra hilly gears FTW) but yes I could clean it up in the future.

[MuirSR]

- Get an SA CS-RK3 (3 speed freehub) and a standard 9 speed cassette - £100 + £15 + £10 to build the wheel
...
Does anyone have any experience of the SA hub - or have a "spare" dual drive hub I could test ?

I can't believe the Sturmey Archer hub is so much cheaper than the SRAM DualDrive! (About half the price.) Any idea how they compare performance-wise?

I note the SA description states you can use a normal front shifter for the hub gears. I'm not sure if the SRAM needs one of its 2:1 shifters or a 1:1 shifter for the hub.

- Higher/Lower gear ranges in 33% jumps (useful for Wales later in the year, stop at the top and bottom to change the front, or just use another shifter for the front gears)

The way HP Velotechnik does this on its trikes is to use bar-end shifters for the front and rear derailleur gears and a twist shifter on the left handlebar for the hub gears.

In virtually any case I'm going to have to get more chains pretty soon - and three chains is another cost in the mix.

How is the "Mick F Long Method" working out. Have you persevered?

[Geriatrix]

Does anyone have any experience of the SA hub - or have a "spare" dual drive hub I could test ?

No spare I'm afraid but I have the SRAM dual drive and I'm very happy with it. It has the advantage that you dispense with the need for a front dérailleur set-up and it resolves (mostly) the recumbent problem of stopping in the wrong gear.
The disadvantage is that it makes the rear wheel a bit more fiddly to remove and hubs are (apparently) not as efficient as chain rings. I haven't noticed the latter.

Would I recommend? Yes.

[[XAP]Bob]

How is the "Mick F Long Method" working out. Have you persevered?

It got a bit waylayed a few times

A new garage will soon be in place, and I'll start again. It does make a noticeable improvement to drive chain performance (can't comment on longevity)

[dkmwt]

You can still keep the bottom end gears when buying from a.n.other.

When you get the new cassette very carefully grid off the rivets that hold the cassette together. Then not so carefully as it's not a problem to put the cassette back together take the 26 tooth sprocket off the new cassette and replace it with the 32 tooth sprocket from the old cassette. You should find that the biggest one isn't very worn. I've had my Trike 7 1/2 years and I'm still using the 34 tooth sprocket.

After grinding the rivets off the cassette becomes a pile of sprockets and spacers so you'll need to rebuild the cassette on the wheel. As long as you get the sprockets the right way up (with a bit of logical disassembly it shouldn't be a problem) the sprockets will only go back onto the hub one way.

Also you'll find it cheaper to buy new chain from ICE as you'll get what you need for a reasonable price. Rather than paying an extortionate amount for 3 chains and only using 2 and a bit.

[Elizabethsdad]

A drivetrain combination that I like the look of is Schlumpf HSD on the front and Alfine 8sp hub on the rear. I got to test ride a Windchetah with the HSD last year and liked it and I am already a fan of Alfine hubs. Another option is fit the Sunstar bottom bracket electric assist kit

[[XAP]Bob]

Id love an hsd. Cost is an issue though.

Bb assist kits are also on (distant) plans.

[Tigerbiten]

A drivetrain combination that I like the look of is Schlumpf HSD on the front and Alfine 8sp hub on the rear. I got to test ride a Windchetah with the HSD last year and liked it and I am already a fan of Alfine hubs. Another option is fit the Sunstar bottom bracket electric assist kit

If your going to use a HSD on a bent trike then you need to combine it with a Rohloff.
It gives you 21 unique gears and a range of 1300%.
Unless your heavily loaded then 11.5" to 150" is just legal, so you can climb anything going up and silly speeds going down.
Main downside is your looking a £2k for the combo, which doubles the price of most trikes .......

[byegad]

If you have a spare wheel why not set that one up with an 11-34 cassette and use it for Welsh hills, saving the original wheel with the cassette of your choice for less 'Geographical' areas?

I have one trike, the Trail, set up for the North Yorkshire Moors and the Yorkshire Dales with a 12" bottom gear, the top is only 84", not an issue in those areas as I spin it out in 1 second flat once the direction is down and a 100" gear would spin out in 2 seconds. I have kept it light and rarely use it on my 'normal' rides.

[Tigerbiten]

If you have a spare wheel why not set that one up with an 11-34 cassette and use it for Welsh hills, saving the original wheel with the cassette of your choice for less 'Geographical' areas?

The original wheel will only take a capreo cassette which limits the options without buying another hub .....

[[XAP]Bob]

I have a spare wheel, with (I think) a default shimano hub.


Although I've just had 5 minutes look, removed 4 links from the chain and replaced the lower jockey wheel (bearnings exploded, and the teeth had almost completely gone...

That might help...

[[XAP]Bob]

I have the CS-RK3.

It's very nice - a MTB shifter under the seat allows me to push up or down a chainring at a standstill. I reckon I have 5 chainrings, with multiple ways to access the middle ones:

These can be run as (Chainring/Hub):
0 - 19.5t from 1/1
1 - 26t from 1/2 or 27t in 2/1
2 - 36t from 1/3, 2/2 or 34.7t in 3/1
3 - 48t from 2/3, 3/2
4 - 64t from 3/3

[[XAP]Bob]

Well, I've just replaced my chainrings, and decided to get a new granny ring, to test...
So I got a 22T granny ring, and the derailleur is quite happy - as a second advantage I can now access the bolts for the outer rings without taking the inner ring off ...

So I can now gear down to 10" and up to 112.6", that's nice and easy to calculate as a 1126% range!

I'm struggling to remember what the actual weight difference was - but it was much less than I had expected. As the wheel is currently being re-dished I can check again when I get it back.
Unfortunately the rims are different so it's not a perfectly fair comparison.