Author Topic: Decisions, decisions... Helios spec + have you got a few things in the bits box? (Read 27619 times)

Kim · « **Reply #25 on:** 21 October, 2013, 12:58:26 am »

Indeed, I reckon Auntie Helen's experiences with the Alfine are probably more relevant gearing-wise (IIRC she has multiple chainrings, but hardly ever uses them).

CrinklyLion · « **Reply #26 on:** 21 October, 2013, 07:07:47 am »

Adding a Rohloff adds the best part of a grand to the price and puts the entire thing out of the question. Not remotely possible! To give it some scale - I am presently considering spending 3 months salary on the project. The rohloff would turn that into more than 4 months....

Oscar's dad · « **Reply #27 on:** 21 October, 2013, 08:29:50 am »

As someone else mentioned get big rotors. We have a 203mm and a BB7 on the back of Tina the Tandem.

I may of missed this but why a hub gear and not derailleurs? One of my bikes has an Alfine 8 and its certainly very good from a low maintenance point of view and the ability to shift gears whilst at a stand still would be very handy on a tandem. But, hub gears do restrict your gear ratio choice.

By the way, I'm not implying any criticism, merely curious

Kim · « **Reply #28 on:** 21 October, 2013, 02:05:53 pm »

I don't know specifically, but with a 20" wheel, there's a strong argument for not having a long-cage dérailleur hanging down, if only because of the way the drivetrain accumulates grass as you ride across a campsite (unintuitively, they tend not to get bashed on potholes and the like, because they're folded up in the sort of gears you tend to hit things at speed in). I suspect that hub gears neatly sidestep the usual problems with the enormous chainrings or Capreo hubs required to get decently high gears, too.

Oscar's dad · « **Reply #29 on:** 21 October, 2013, 02:09:46 pm »

^^^ Good points.

mrcharly-YHT · « **Reply #30 on:** 21 October, 2013, 02:17:52 pm »

Regarding the ergon grips; Simon (interzen) has some Evan's-own grips and rates them higher than Ergons. Significantly cheaper, too. I think they are these ones:
http://www.evanscycles.com/products/fwe/ergonomic-grips-ec040107

Hub gears make sense for being able to change down when stopped - important maybe when you have a SmallStoker on the back.

OTOH, a short-cage rear and compact micro-drive front would give lots of low gears, some middling high gears. I doubt a Crinkly+SmallStoker are going to want to push pedalling at warp factors. I wouldn't, due to the feer.

dasmoth · « **Reply #31 on:** 21 October, 2013, 05:24:10 pm »

I've got a spare set of bars with Ergon GP1 grips and matching bar-ends. Taken off the back of our tandem when Emily decided she preferred bullhorns. They're pretty-much identical to the setup I'm still using at the front.

They've got a slight rise to them -- not sure if that's a good thing or not.

But all yours if you want them.

DrMekon · « **Reply #32 on:** 21 October, 2013, 05:48:45 pm »

Fwiw, I've got the cheaper br505 discs, alfine 8 and the 20t sprocket. Brakes are great - i don't need more. Gears - would like lower, but can cope. However, me and my sever year old can spin out with a tailwind. Still, if money it tight, it's not a deal breaker. Alfine 11 wasn't out when we got out Helios.

They are absolutely brilliant.

If I was going to upgrade some more, nokon cabling would be my first upgrade. It's a really long cable run, and I think between cable stretch and outer compression, lever fell might be improved. Also, it would look cool.

L CC · « **Reply #33 on:** 21 October, 2013, 07:54:42 pm »

I (think- might have disappeared in the house move) also have flat bar & ergons & bar ends. Will have a hunt & pop 'em in the post. You can then bin or flog as required.

CrinklyLion · « **Reply #34 on:** 22 October, 2013, 07:02:54 am »

Cheers!

I don't know how much of the core components (as opposed to the optional upgrades) I can swap or supply - but those would mean I could get the bike supplied with the bars the chap at the LBS suggested with a bit of sweep and have the choice of swapping round to find out what suits best

I've written to the bank and am awaiting funds, and have emailed the LBS back to say I'm pondering whilst I wait. I think I need to have a conversation with them about crank lengths, chainring and sprocket sizes and gear inches and risk looking like a bike-geek.

tiermat · « **Reply #35 on:** 22 October, 2013, 08:08:53 am »

I happen to have, in the ~~shit heap~~ garage'o'doom, a set of BB7 (MTB) that I purchased from Interzen OTP.

They may well have the rotors with them, but most deffo have the levers and cables (and pads).

Any interest to you?

Butterfly · « **Reply #36 on:** 22 October, 2013, 11:41:49 pm »

I have slightly swept back bars (City Sweeper, according to the sales invoice) on my Helios, which are great.

The Hebie Bi Pod stand is useful as is the bottom gear of 20 or so inches.

The crank shorteners from Circe are really good. I have a strengthened Blackburn rack on the back so that I can fit a baby seat. If you are ever going to need this option (for nieces and nephews etc) it's worth getting Circe to do it. They also found a way of fitting a rear light so that it didn't block the babyseat from fitting. I have a spare thud buster seat post for use with adult stokers. I definitely recommend shorter cranks if possible.

L CC · « **Reply #37 on:** 23 October, 2013, 08:23:47 am »

Quote from: fboab on 21 October, 2013, 07:54:42 pm

I (think- might have disappeared in the house move) also have flat bar & ergons & bar ends. Will have a hunt & pop 'em in the post. You can then bin or flog as required.

Gone, I'm afraid. Landfill-ing of bike parts, I am ashamed.

Chris S · « **Reply #38 on:** 23 October, 2013, 09:03:36 am »

Quote from: fboab on 23 October, 2013, 08:23:47 am

Quote from: fboab on 21 October, 2013, 07:54:42 pm
I (think- might have disappeared in the house move) also have flat bar & ergons & bar ends. Will have a hunt & pop 'em in the post. You can then bin or flog as required.

Gone, I'm afraid. Landfill-ing of bike parts, I am ashamed.

Could be in my garage.

clarion · « **Reply #39 on:** 23 October, 2013, 09:41:33 am »

Chris' garage == landfill

Chris S · « **Reply #40 on:** 23 October, 2013, 09:58:54 am »

Quote from: clarion on 23 October, 2013, 09:41:33 am

Chris' garage == landfill

You've seen it then!

Tewdric · « **Reply #41 on:** 23 October, 2013, 10:33:37 am »

Alfine 11 hubs can be used with a maximum 23t sprocket according to the tech docs (so I guess they are saying its fine with nexus sprocket), but a low ratio set up i.e. anything smaller than about a 44 at the front, will give the potential to put a huge amount of stress through the hub on a loaded tandem. Rohloff are quite strict about how low you can go but I can't find anything official from Shimano other than recommending 18-23 sprockets and a 1:1.9 ratio. I guess this assumes a large wheeled solo though.

I'd be discussing it with the LBS and tempted to err on the side of caution - something like 39/20, on the basis that I'd rather walk up the steepest hills and lessen the chances of mashing my hub innards. These hubs any turn out to bombproof but we don't really know yet!

clarion · « **Reply #42 on:** 23 October, 2013, 10:41:02 am »

Quote from: Chris S on 23 October, 2013, 09:58:54 am

Quote from: clarion on 23 October, 2013, 09:41:33 am
Chris' garage == landfill

You've seen it then!

It's twinned with our dining room.

LittleWheelsandBig · « **Reply #43 on:** 23 October, 2013, 12:10:32 pm »

Any suggested ratio limit for the Alfine 11 hub would allow for 170 or 175 cranks and no smaller than a 559 wheel. Given that this bike will run 406 wheels and possibly shorter cranks, I'd not be concerned by similarly reducing the ratio limit.

Tewdric · « **Reply #44 on:** 23 October, 2013, 01:49:58 pm »

Don't small wheels actually make it more likely that you'll lunch the hub? It's making my head hurt thinking about it..

Kim · « **Reply #45 on:** 23 October, 2013, 01:59:49 pm »

Quote from: Tewdric on 23 October, 2013, 01:49:58 pm

Don't small wheels actually make it more likely that you'll lunch the hub? It's making my head hurt thinking about it..

Nahh, the opposite - you're moving less road per turn of the hub. ie. gearing down, reducing stress on the hub.

Andrew Br · « **Reply #46 on:** 23 October, 2013, 02:01:45 pm »

I've also thought long and hard about it and the conclusion that I've come to is that I think it's OK; the hub only sees the torque coming into it. The gearing afterwards doesn't matter.
I think.
I'll now wait patiently for someone who knows to put me right.

ETA: beaten to it by Kim.

Tewdric · « **Reply #47 on:** 23 October, 2013, 02:33:08 pm »

To my addled brain smaller wheels and lower ratios both allow more torque to be delivered to the hub internals. Yep it's what's going in that counts but that's a function of what is going out!

Kim · « **Reply #48 on:** 23 October, 2013, 02:44:13 pm »

Quote from: Tewdric on 23 October, 2013, 02:33:08 pm

To my addled brain smaller wheels and lower ratios both allow more torque to be delivered to the hub internals. Yep it's what's going in that counts but that's a function of what is going out!

Exactly. A smaller wheel means that less torque is going out for a given force on the tyre (we'll assume that a 20" tyre and a 26" tyre slip at the same force, which defines the upper limit).

Treat the wheel as a class 3 lever (fulcrum at the axle, force applied somewhere in the hub, load at the tyre), and the larger the diameter, the longer the lever and the less mechanical advantage it has. Less mechanical advantage means more force exerted by the hub to achieve a given force at the tyre.

clarion · « **Reply #49 on:** 23 October, 2013, 02:50:12 pm »

Kim used the 'L' word, which I was going to pitch in if we hadn't resolved it.