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-   -   Brompton upgrades: my stupidly expensive way to buy a Brompton :-) (https://www.bikeforums.net/folding-bikes/880706-brompton-upgrades-my-stupidly-expensive-way-buy-brompton.html)

alhedges 03-31-13 11:48 AM

Brompton upgrades: my stupidly expensive way to buy a Brompton :-)
 
I bought my Brompton in 2011 (back when there was only a 5 week wait for BTO). My short test ride convinced me that the stock three speed set up 50/13 was fine, and I decided I didn't need a rack, so I got an M3L with the Shimano dynamo.

I pretty quickly discovered that I'd made a mistake with the gearing: it turns out that the low gear was about what I liked as a cruising gear; 2d gear was good for downhills, and I never really used third gear. I think this gear set up was 48-64-85.

I also decided I wanted a rack, for stability when standing as well as for "overflow" when shopping.

So the first thing I did was buy the rack kit and add it. This was more expensive than it would have been to order the rack with the bike because you also have to order a different fender. Also, it just is.

The next thing I did was to replace the halogen bulb that came with the Shimano hub with a lumotec LED light (the one that comes with the Schmidt dynamo). Unlike my other upgrades, this resulted in a significant savings: the shimano hub and dynamo cost around $110; the new LED light cost around $100-$120 (I'm not sure); but the Schmidt hub/light combination was about $500. I would recommend this approach to anyone.

But I'm still left with the high gears. So the first thing I do is buy the 44T crank and and install it. This wasn't too expensive - maybe $60? This made a significant difference, taking me down to 42-56-75, but still not quite where I wanted to be. So I switched the 13T rear cog for a 14T cog and I was at 37-49-65. This put me roughly where I wanted to be, in the sense that the mid gear was a good cruising gear, the first gear was appropriate for hills, and I did use the third gear occasionally. But I still wanted a lower gear.

So I bit the bullet and had my shop order the parts to upgrade to a six speed. This was pretty expensive - around $500, I think, primarily because you have to order a new wheel with the BWR IGH, rather than with the BSR hub that comes with the 3 speed. It also took something like 8 months for the parts to come in! Presumably because they were using them for the new bikes that were backlogged - there may have been a bottleneck with the IGH, but I'm not really sure what the issue was.

Anyway, it finally showed up about 3 weeks ago and the shop installed it for me (they did it free because of the wait, which was nice), and, at least for now, the bike is perfect. Gearing is 29-36-46-56-72-88, which gives me an extremely useful 29" gear, the 36" gear that I'm pretty used to, and two useful cruising gears - 46 and 56, as opposed to the one useful 49" I had before. 72" is useful going down hills, but I haven't used the 88" much.

It took me a couple of minutes of thought to figure out how to navigate the shifters, but it turns out it's extremely intuitive.

So apparently my job is to serve as a warning to others, at least in this context. Here is the warning (it has several parts):

1a. Do not buy the 3 spd Brompton unless you are ABSOLUTELY certain that you won't want different gearing.

2a. You won't be absolutely certain that you won't want different gearing unless you are buying your second Bromtpon.

2. You should *probably* just buy the 6 spd, but if you think you won't need all of those gears, buy the 2 speed (or single speed). That way, when you upgrade, you won't have bought *two* IGHs for one bike. (Also, the weight savings between a two speed and a 6 spd are significant; between the 3 speed and 6 speed they are not.

3. For God's sake, get the reduced gearing option unless you are going to be racing the bike or live in a town which only has hills that run downhill! (It's not a big deal or very expensive to switch if you have the right tools, however, but it's better to start low and go high than vice-versa because you are more likely to want low).

4. I think it's okay to wait on the rear rack - there's not that much of a premium to install the new one, nor is it that complicated.

5. The budget choice is to get the shimano dynamo and add the lumotec LED headlight (at least until the Shimano choice comes with an LED option.) But the SON hub is nice (and very shiny), so if you're not that price sensitive, you might want to go for that.

The cool thing about Bromptons, of course, is that you can upgrade, even years later. I kind of knew that when I bought mine, although I didn't quite realize I'd have to get a new hub to upgrade to 6. But it's still pretty awesome!

(The new wheel that I got is the new 2013 wheel with the double wall rim, so there is that).

fietsbob 03-31-13 01:27 PM

Got a used Mk2 T, sort of the M3R of the day, living in a hilly town
1st gear option, a Front derailleur mount kit, to fit a 52-36 cranks ,
but recalculated the gear that offered, set it on a shelf
(it, the FD adapter kit, for sale if anyone is interested?)

and doubled the investment in a Schlumpf - Brompton version of the mountain drive crank ,
a 54, kicked down the low is as if a 21.6t [ 50/20 is even numbers]

Mk3 bike they went to Sachs for the 3by2 hub, and that one they used the same AW3 spline,
just made 3 teeth shorter on the 15t, a 3/32 thick cog.. I got one of those..

3 speed is run through twice, 3<>4 double shift easy with 2 planetary gears.

it's what Rohloff does inside their hub in 7<>8..

bhkyte 03-31-13 02:43 PM

I guess the lack of gear options is the thing that can make a bromptom or upgrading a bromptom an expensive process/ mistake.
When will they bring out a 135 rear axle model?
I have a 5 speed that I got very cheap. That I recently worked out cost me around £200 ish to get the riding position right and a few basic upgrades.

How much did it all cost in the end out of interest?

fietsbob 03-31-13 03:09 PM


When will they bring out a 135 rear axle model?


You got small shop modifiers like Steve Parry and the Kinetics shop up in the Scottish north
taking up that challenge.

so You dont have to wait for the company to make a new rear portion, to satisfy that desire.

Here you go .. : http://www.kinetics.org.uk/html/rohloff.html

alhedges 03-31-13 03:23 PM


Originally Posted by bhkyte (Post 15451965)

How much did it all cost in the end out of interest?

I'm not precisely sure, but it looks like I paid about $750 or so for upgrades that would have cost about $200 if I'd ordered them at the time.

dynaryder 03-31-13 03:33 PM

Curious as to why you bought the whole 6spd setup,and not just the derailleur? Will the BSR hub not take the dual cogs? If it will,your gear range would have been narrower,but it would've saved a bunch of money and effort.

alhedges 03-31-13 08:01 PM


Originally Posted by dynaryder (Post 15452177)
Curious as to why you bought the whole 6spd setup,and not just the derailleur? Will the BSR hub not take the dual cogs? If it will,your gear range would have been narrower,but it would've saved a bunch of money and effort.

I think the BSR would take the dual cogs, but the low end would have only gone down to 34, and I wanted it to go lower.

fietsbob 04-01-13 12:02 AM

The Driver on the BWR is for a whole different cog, Splined, Shimano BMX type (my guess)

BSR is still AW3 cog, while SA was in turmoil they went to Sachs ,
and they supplied the 1st version of the 2 by 3 hub .. and there they made the driver
wider, to take 2 cogs a spacer and the snap ring.
a thinner version of the AW3 hub cog.. the 15t has 3 shorter teeth for the shifting..

To take 2 cogs the BSR would need a driver transplant.. BWR is wider ratio spaced, than the Sachs or the AW3/BSR.

wilfried 04-01-13 12:08 AM

I agree completely about getting a 6 speed. I got my Brompton M3L from a friend and paid less than half retail, so I can't complain. Three speeds is perfectly adequate for the mostly flat terrain around here, and I basically only use gears two and three, gear two to start, and gear three to cruise. However, when I've taken my bike to hillier places, I'm really working up hills. On an 8 or 10% grade in first gear I'm standing on the pedals and pulling on the handle bars, and I'm still barely moving, never mind the stress on the drive train, and I dearly wish I had a lower gear to work with. Occasionally a higher gear would also be nice. Third is fine for flats, but it'd be fun sometimes to push the speed a little on long, uninterrupted runs (I usually ride in city traffic, so there usually isn't much opportunity for that). I also spin out quickly downhills. I've vaguely considered upgrading, but $500 is awfully steep, and almost the price I paid for the bike!

Given what I just said, I can't agree at all with your point #3, at least in flat areas. You cruise in first gear? Really? I can't imagine; I hardly ever use first. I'd be going at a snails pace, and spinning out constantly. Like I said, I almost always ride in third, and climb mild hills (like crossing a bridge) in either second or third, depending on how hard I want to work. I guess I'm a masher rather than a spinner, but honestly, third gear isn't all that high, and first, except on moderate hills, is awfully low.

bhkyte 04-01-13 03:46 AM


Originally Posted by fietsbob (Post 15452081)


You got small shop modifiers like Steve Parry and the Kinetics shop up in the Scottish north
taking up that challenge.

so You dont have to wait for the company to make a new rear portion, to satisfy that desire.

Here you go .. : http://www.kinetics.org.uk/html/rohloff.html

I am aware of these thanks.
I asked when will Brompton make one.

fietsbob 04-01-13 09:27 AM


I asked when will Brompton make one.
course Brompton would know, send a email.
I dont think anyone posting here works in Mgmt, there...

bhkyte 04-01-13 11:21 AM

Next time I post a rhetorcial question I will be sure to underline it? Lol

Ozonation 04-01-13 11:50 AM


Originally Posted by wilfried (Post 15453799)
I agree completely about getting a 6 speed. I got my Brompton M3L from a friend and paid less than half retail, so I can't complain. Three speeds is perfectly adequate for the mostly flat terrain around here, and I basically only use gears two and three, gear two to start, and gear three to cruise. However, when I've taken my bike to hillier places, I'm really working up hills. On an 8 or 10% grade in first gear I'm standing on the pedals and pulling on the handle bars, and I'm still barely moving, never mind the stress on the drive train, and I dearly wish I had a lower gear to work with. Occasionally a higher gear would also be nice. Third is fine for flats, but it'd be fun sometimes to push the speed a little on long, uninterrupted runs (I usually ride in city traffic, so there usually isn't much opportunity for that). I also spin out quickly downhills. I've vaguely considered upgrading, but $500 is awfully steep, and almost the price I paid for the bike!

When I was looking for a Brompton last year, I test rode a Brompton from a dealer who had a regular 3 speed model, and when I struggled on a hill, the low end was just not low enough. When I tried a 6 speed, it was a lot better.

But rather than waiting 5 or more weeks for BTO from a dealer, I just phoned every dealer in Canada to see what they had on hand. By chance, a dealer in Victoria that I bought the bikes from had a M6R model with the reduced 6 speed gearing. I was a bit concerned that this lower gearing was specific to Victoria (hills, coastal mountains, or with the many retirement communities, buyers were more interested in recreational riding), but the very knowledgeable sales rep said that his experience with customers was that the regular gearing was just a bit too high and felt awkward - even on flats - and that the reduced gearing was more versatile. Plus, he commented that the situations in which you use a Brompton probably demand less all-out-speed, and more up and down travel.

He was right. Even though where I live is pretty flat, the reduced gearing is very versatile. There are often more "hills" than you'd expect, such as going up and down overpasses, stop-and-start traffic, and good grief, riding into the wind - always a pain.

alhedges 04-01-13 02:11 PM


Originally Posted by wilfried (Post 15453799)

Given what I just said, I can't agree at all with your point #3, at least in flat areas. You cruise in first gear? Really? I can't imagine; I hardly ever use first. I'd be going at a snails pace, and spinning out constantly. Like I said, I almost always ride in third, and climb mild hills (like crossing a bridge) in either second or third, depending on how hard I want to work. I guess I'm a masher rather than a spinner, but honestly, third gear isn't all that high, and first, except on moderate hills, is awfully low.

It looks like you are the person they bike was designed around. Maybe you have English blood?

Yeah, I'm pretty happy cruising around 50 or so, which was unfortunately first gear on my 50x13 ver. 1.0. Does your M3L have standard or reduced gearing?

fietsbob 04-01-13 03:22 PM

i reduced the gearing with a bigger rear hub cog.. 2 more teeth.
then the crank, a 130 BCD MD, came with the big 54t..

now: 77.1; 57.9; 43.4;.. 30.8; 23.1; 17.4

if I put the 13 back on : 89; 66.8; 50.1;.. 35.6; 26.7; 20..

47:13 would get me close to 54:15 . again .. 3.6:1

Sammyboy 04-02-13 07:57 AM

I cannot recommend going with the low gearing; test ride one first. I think 70% of people will want standard; on a standard 3 speed, the top end is what I find lacking. I had a 6 speed, which was fine except that the double shifter arrangement is massively cludgy to get only 6 speeds. I also got the rack, and would again, but not the dynamo hub, and I regret not springing for that.
mo
When I incredibly stupidly lost that bike out of the back of my car, I bought an older, much upgraded replacement. I have the old SA 5 speed hub, and even though the gear range is less than the 6 speed, I greatly prefer not having the double shifter thing. What it really wants, of course, is a Nexus 8 or an Alfine 11; given that aftermarket people can do the rear triangle, I'm amazed Brompton haven't. New/old bike has no rack, and whilst that's rarely a problem, I'd like one. The 6 speed double shifter debacle is a solution looking for a problem; given how well thought out almost everything on the bike is, I find it hard to understand.

chagzuki 04-02-13 09:26 AM

I just argued the opposite case on another thread, Sammyboy. I can see why they stick with 3 speed hubs that have 94% efficiency ratings given that the tensioner is inefficient Since the tensioner has to be there it makes sense to use it as a derailleur and keep the highly efficient and very light hub. I've not seen any efficiency stats for the alfine or nexus 8 but I doubt they beat a Rohloff which tends to be around the 88-92% mark depending on the gear.
I was on the verge of switching my 5 speed hub out for a standard Brompton 6 speed configuration since the overall grindiness was often too unpleasant, but I've just converted it to oil and it's now feeling much smoother.

fietsbob 04-02-13 11:44 AM


I have the old SA 5 speed hub,
couldn't be that old , they used to have 2 pull chains, to shift them, one out each end of the hub.


got a Tacx sealed-bearing pulley 10t set to put on the 3 speed chain tensioner..

that is practical to do , but the 6 speed uses the proprietary pulley,
the flanges and pulley, are molded in one piece,
the changer fork shoves the pulley sideways by the flanges..

quite simple and more compact and takes up little room, compared to
using a regular derailleur.. nothing to bang out of index synch.


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