Category Archives: Tweaks

Ralph-e’s overdue Hack?

Ralph-e (my Alfine 11-speed Brompton – with a GrinTech electric conversion) has had a frustrating “chain drop” issue throughout the 5 years we’ve been together. With “Murphy’s Law” timing, infrequently the chain can be dislodged from the rear cog & chain tensioner sprockets. I’ve developed a second-sense feel for a successful unparking step, although I admit to including a quick look down at the chain at the rear hub before attempting to ride away. 

The following 3 pics illustrate the scenario: (1) taut chain over the rear cog, (2) slight reduction of tension in the chain (where the chain is sagging & starting to slide down & out over the widened rear frame), (3) further reduction of tension (resulting in further chain sag over the frame & commencement of the chain moving off the teeth of the cog). At this point, if the rear wheel rotates backwards then the chain will fall off the cog & then off the tensioner sprockets. The reduction in chain tension usually comes about when parking/unparking & as long as back-pedaling is minimised then chain drop can be avoided. I believe the Alfine hub also has some slight drag when rotating backwards & so vigorous back-pedaling while riding can also achieve increased chain slack & sag over the rear frame tube; hey presto, chain drop?!



Now I think I may have resolved the issue, through setting up a “chain keeper” for the section of chain closest to the rear cog (thereby maintaining chain alignment over the cog teeth). The next 2 pics show my chain keeper in situ with the chain taut (pic 1) & chain sagging (pic 2). My keeper?: a large-sized cable tie (working great). Maybe not what Brompton would do?

Cage revision

My bidon cage system had a minor improvement recently so I thought I should post the latest version info.

The change was to using clear tubing as insulating protection where the cage contacts the stem (I’d previously used various rubber pads but their attachment wasn’t ideal – no issues in practice but “could do with fixing”). The other components are two aluminum strips (8mm by 3mm), some fixings & two 58mm ID O-rings.
Taking a standard bidon cage & assembling my bits, it’s ready for attaching to a Brompton stem…
Once in place, the system looks like this…

Probably my longest running & most essential “hack”, the system performs perfectly. A bidon is held securely & the system doesn’t move around, although it’s also able to be swung left or right if necessary (e.g. folding the bike with a luggage bag in place or folding the bike for packing). The system is able to be removed readily but I’ve actually never needed to take it off. Of course, there’s bound to be another version at some stage – & I’m thinking 3D-printing could be utilised?

Monkii revival

Updated – 7/1/17 (refer end of post)

My Brompton bidon cage system is still my favourite but it doesn’t suit someone that wants to use their folded Brompton as a shopping trolley, with handle bars unfolded & a bag on the luggage block – because the cage would foul the bag & regularly removing/installing the cage is best avoided. (Whoops, see update below.) A cage that is readily removable is the Monkii system but after trying one for some time, I’m not keen on 2 aspects of the design. First, I don’t like strapping the bottle to the cage & having to remove the two together when drinking. The killer issue though, is that the Monkii cage can readily be ejected when riding over bumps. So, here’s my attempt at fixing those 2 issues…
Peregrine with the old system… 

 
… & Clarence with the new setup… 

 Here’s a pic of the old & new components… 

 
Recipe: take one Monkii system, remove the strap & cut off the wings & tail of the cage. Drill & countersink the cage spine & attach to a standard cage with some screws & nuts. When the Monkii stem block is being mounted, hook an O-ring under the block. When installing the new “combo cage” to the bike, hook the top of the cage under the O-ring & stretch it up so that the Monkii portion of the cage can be connected to the Monkii stem block. 

 
So, I now have a Monkii system that lets me easily remove/attach the bottle when drinking & won’t become disconnected over bumps – & lets me readily remove the cage when operating in “shopping trolley mode”!

Update: Since using Ralph-e & trying to avoid removing the luggage bag (& disconnecting the battery), I now realise that I can leave my Bidon in the cage system & the bag just pushes the Bidon to the side (as the bag pivots around while folding the front wheel).

Flat insurance

I’m hoping I’ve maxxed out my “flat insurance”, with the purchase of a “Kool-Stop Tire Bead Jack” (sorry about the spelling).
This little device now sits in my Brompton bag, ready for service to assist with reinstalling Marathon tyres. I’ve frequently posted about the difficulty of installing any tyre onto Ralph-e’s Alfine 11-speed rear wheel, having a Sun CR18 rim. The rim well is very flat & leaves little space for centreing a tyre while easing a tyre bead over the rim. I believe a Velocity Aeroheat rim resolves the issue but I’ve been slow to obtain one (& then rebuild the wheel). Noting that Ben Cooper at Kinetics regularly produces Rohloff & Alfine-equipped Bromptons with the CR18 rim, I wondered why he didn’t use the Velocity rim. To my surprise, he claimed to not have any trouble fitting tyres – but then confessed that, “I cheat! There’s a gadget called a Simson Tyre Mate (now branded Kool-Stop) which makes it easy…”!

Ralph-e extras

Tools –

Along with my Brompton toolkit (stored on-board), here’s Ralph-e’s luggage bag set of tools.
There’s a few new items that most Brompton owners wouldn’t include but you’ll probably pick them from the descriptions below.

  • Brompton toolkit
  • 17mm front wheel nut ring spanner
  • Spoke tool
  • Allen keys
  • Pocket knife/scissors for heat-shrink removal
  • Electrical & duct tapes for cable repairs
  • CO2 inflator
  • CO2 cartridge
  • Tyre levers
  • Puncture repair kit
  • Tyre pump – Topeak MiniDualG
  • SV4 tube (in addition to one in the mainframe)

Tweaks –

Knowing Ralph-e was going to become considerably heavier after the electric conversion, & probably needing good stability when folded & rolling, in preparation I moved/robbed Robinson’s rear rack (after all, the rack weight was unlikely to be noticed on Ralph-e & Robinson’s role as “spare” would just as easily be accomplished as an M6L?). This turned out to be a very worthwhile operation. However, what I hadn’t anticipated was the borderline stability when Ralph-e was folded (especially with the luggage bag fitted). With the front wheel motor & battery weight concentrated outside the center-line of a folded Brompton, great care was needed to avoid toppling when transporting, etc. Seeing a BikeFun Eazy wheel extender on a Brompton at the Urban Challenge, what I may have considered as “functional bling” now leapt into mind as “essential function”? Sure enough, BikeFun’s brilliant gadget was right at home on Ralph-e & has quickly been integrated into the Brompton fold sequence (i.e. “Left pedal down, right wheel out, park, etc…”)

Progress –

Two aspects of life with Ralph-e have been pleasing. Beforehand I’d wondered if the weight would be a concern when folding/handling/etc & I also pondered if converting my Alfine 11-speed Brompton was the thing to do? Sure I’d like less weight but I’m coping & learning more. The knack to folding the front wheel is first to anchor the bike down by putting my toes on the rack/left-side Eazy wheels & then grasp the handlebars by each grip & lift well up until the front wheel naturally pivots around under its own weight (& the same for unfolding, where the increased weight pivots the front wheel very readily). If/when I need to lift the folded bike, my right hand grasps the mainframe just behind where the front tyre is close to the frame & my left hand lightly holds the luggage bag handle for balance. (Leaving the bag on the bike saves the inconvenience of disconnecting the battery in the bag. I’ve seen systems that allow an automatic electrical disconnection through the luggage block; maybe one day but so far so good?)

My logic for converting the Alfine Brompton was somewhat guesswork. A brief test ride of a 6-speed Brompton fitted with a cadence-based pedal assist (not a torque sensing system that I was intending) showed the disadvantage of stopping pedaling to change gear; the power goes away & your next pedal action has to start the motor again. (Brompton hub gears don’t like gear changes with pedal load whereas the Alfine hub can change gears under load, allowing me to keep pedaling & just change up or down through the 11 gears as necessary.)

My medical condition necessitates low gearing on my Bromptons. 6-speed Clarence & Robinson both have 40T chainrings & Ralph-e’s Alfine 11-speed has a 44T chainring. Ralph-e has 2 gears lower than a “reduced” 44T Brompton’s lowest gear (3 lower than a standard 50T unit) & an upper gear equal to a 44T bike. Before the electric conversion, I would start changing down early at hills to minimise fatigue & maintain some momentum. Now I’m having to re-learn many riding strategies when I can ride harder in higher gears & then quickly change down as/when necessary. Ralph-e’s lowest gears are getting a lot less use & I’m constantly changing up & down through the gears. I’m also learning about the e-bike setup with a torque sensing bottom bracket (supplying power to the motor proportional to my pedaling load). For example, on a recent gradual small rise Mrs Aussie had been well ahead but I quickly caught back up when she naturally slowed on the hill. I assume that the increased pedal pressure on the hill had the torque sensor supplying more power & I was accelerating up the hill while just maintaining my cadence? (A bigger hill would have seen me increasing my effort & changing down but this time I had a “magic carpet” sensation?) Every ride is a delight, with the power feeling smooth & natural with just my pedaling – “as it used to feel but now even better?”

Another aspect of the pre-conversion conundrum was Pedelec vs Throttle. I wanted to be able to ride my bike as naturally as possible & preferred to avoid using a throttle (assuming it to lessen the natural riding experience, although the sensation of opening a throttle & enjoying a surge of power is very appealing?). As such, I liked the theory of a torque sensing pedal assist, (as compared to the straight-out cadence measuring system) & thought I could get by without combining it with a throttle. During my first days with Ralph-e & experiencing big hills, I temporarily fitted the throttle supplied with the conversion kit, to see if it was going to help. I found that it didn’t provide any more power from the motor over what pedaling was achieving (& that pedaling was essential, rather than expect to ride on throttle alone!). The throttle is now consigned to the luggage bag, just in case the TDCM bottom bracket should fail far from home?

Interestingly, my brief test rides with various throttle systems has shown quite some differences. I don’t just mean thumb-control vs twist-grip; factors such as smoothness, sensitivity & effort were all on display. Also, the ergonomics come into play when some bike setups require a throttle on the left. One aspect for me about using a throttle, is that I would be using it everywhere; I need the motor on flats as well as hills (unlike some riders who would just use a throttle to help the effort on hills). I’m kind of glad I’m not having to choose or depend on a throttle?

Ralph-e learning

My new ebike world is progressing nicely. So far, rides on Ralph-e (a recent electric conversion of my Alfine 11-speed Brompton) have totaled about 200km along mostly coastal bike paths. Mrs Aussie has laboured somewhat while I basically cruised (the reverse of our previous ride efforts for some years?). I coped with savage headwinds & stiff hills without much concern, although a certain amount of guilt nags away (for a while?).

My technicalities recipe is to take one Brompton, add a 250watt Crystalyte motor to the front wheel & mount a 20amp GrinTech controller above the rear of the front mudguard…
Fit a TDCM torque sensing bottom bracket, with a hole drilled in the bottom of the frame for the cable connection…
Mount a GrinTech Cycle Analyst computer to the handlebars & join everything together with a wiring loom…
…and finally, include a battery (in my case, an eZee Lithium-manganese 36volt 15AmpHour, i.e. 540WattHours) within a Brompton bag at the front…
The whole experience has been an illuminating & exciting learning curve, from the ride characteristics (sounds, power-off lag (especially on slow-speed maneuvers) & smooth power) to the technical data available from the computer system (up to 11 displays for ride, motor power, human power & energy data). Choosing to “go electric” was a concern for an appropriate ride experience (brilliantly answered?), a quality product (very satisfied, even considering the likelihood of an eventual Brompton ebike release?) & a deciphering of all manner of ebike jargon & implications (eg cost, weight, power & range?).

The info & stats from the computer display has provided insights & understanding for my ebike adventure. Rather than the experience of observing a series of lights representing battery level or power levels, while riding I can see the exact consumption from the battery (amphours), my output level (human watts), economy (watthours consumed from the battery per km ridden), the usual bike computer data – & other stuff I’m still getting my head around. However, determining the all-important battery range is still a work-in-progress while my economy level has been improving with re-configuring & fine-tuning for power output. So far, a range exceeding 100kms (depending on the demands of the ride?) is on the cards – although probably not on my agenda?

Brompton weight was something I could estimate pretty accurately (about 4kg?) before the conversion although battery weight was an unknown while I was unsure what battery size to use. The 540Wh unit I decided on is great for range but adds another 4kg in weight. As usual, front luggage weight on a Brompton has virtually no affect on ride handling. I’m becoming quite proficient at folding Ralph-e with the front bag in place & the folded handling has been helped with the inclusion of a rear rack.

The final word on my Brompton ebike experience to date: priceless!

Introducing Ralph-e…


i.e. “Ralph” (my Brompton Alfine 11speed) plus a Grin Technologies Brompton conversion kit equals “Ralph-e”

My previous blog post on “Electric patience” mentioned a coming electric conversion of one of my Bromptons, rather than wait out the eventual (?) release of a factory electric Brompton. What I’ve now got from Glow Worm Bicycles (thanks Ali, Maurice, Tim, Manny, et al) is possibly my ideal setup: a Pedelec Brompton, requiring that I still have to pedal everywhere but providing electric motor assistance for hills, etc.

Ralph-e has a torque sensor bottom bracket (& no throttle control), a comprehensive computer display & a whopper battery. There, that’s my technical info nicely simplified – until a future post? (Oh, & the setup is capable of regenerative braking if I add the e-brake levers but for now I’m unsure if I’ll bother.)

So far my little solo test riding has shown an enhancement to my “Brompton Grin” & I’m quite hopeful of comfortably keeping up with Mrs Aussie? We’ll see.

Electric patience

I’m trying to be patient & any day/week now there should be a call? My patience for the electric Brompton has been frustrating, with so many rumours & release expectations. It’s been a constant for many years, as has my need for low geared bikes to provide assistance for riding with a heart condition. I can choose between six-speed Bromptons with 40T cranksets or an Alfine 11-speed with 44T but under some riding conditions I’m still struggling at walking pace. So the desire for a Pedelec Brompton (one that I still have to pedal to get electric motor assistance, rather than just push/twist a throttle) has been a hope for “normal cycling”. Will the electric Brompton dream eventuate?

Recent news from Brompton on a likely introduction is the latest release info, but wasn’t very encouraging from my point of view. The Brompton announcement (http://www.brompton.com/News/Posts/2016/Electric-bike/) has expressed the release as “selected European cities in Summer 2017” (i.e. maybe July 2017?) but who knows when for the global market?

Armed with some “UK-trip scuttlebut” & fresh research, I decided to check out local offerings for the possibility of a Brompton conversion. My initial findings weren’t very encouraging for obtaining a satisfactory product – but then I visited a shop where their conversions matched my quality & engineering expectations. At present I’m not going to mention the business name owing to various reasons – & Brompton restrictions? – but suffice to say they now have one of my Bromptons for conversion.

Progress has been slower than I’d like due to workloads & component supply but really, everything is bearable in comparison to the alternatives? The conversion components are from Grin Technologies, a Canadian company that offers a Brompton kit (http://www.ebikes.ca/product-info/brompton-kit.html/) with various options; my choices to be revealed once my Brompton is completed. Fingers crossed for that call soon?

Clarence mods

Clarence, my new Claret colour Brompton S6L, has undergone some recent mods. Before I get onto telling what I’ve done to Clarence, I’ve got to thank Brompton Australia for their efforts. In my blog posts I’d previously mentioned my liking for the colour & that I’d been offered the stock bike currently on its way to Australia. What I hadn’t mentioned was that the bike arriving was an M6L & that Brompton Australia had offered to convert it to my preferred flat bar S model. With the cessation of the colour choice, it was a deal that I couldn’t resist.

So what have I done to my newly converted S6L? Some of the mods are simple additions or replacements that may or may not show up in the pic below? They include an AussieOnABrompton.com frame decal, Brompfication hinge clamps, front & rear lights, Cateye Strada computer, Brompton Eazy wheels, my Bidon cage setup, Presta-valved tubes & a Tiller Cycles 40T crankring.
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For two of the important body-contact areas (bum & hands) I just had to repeat mods from other Bromptons: a Brooks B17 saddle & Ergon grips. It took some time to decide the saddle colour but I eventually settled for black. However, a set of Ergon GP1 grips was a harder mod than I expected. Whereas Mrs Aussie’s Peregrine setup with Ergons was straight-forward, Clarence proved difficult. The pic below shows the state of the original grips removed – & probably indicates that Brompton Australia’s budget for handgrip adhesive (used during the conversion from M to S bars) is far too high?
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Finally, a comment on two mods that I haven’t made (for the moment). I’m sticking with the standard Brompton tyres (whereas Schwalbe Marathon & Marathon Plus tyres are used on our other Bromptons) & it will be an interesting evaluation/comparison? The standard Brompton pedals too are an experiment; my usual choice is MKS removable pedals where I use flat or clipless versions as required (mostly clipless). I have no idea how long this trial will last.

Bag & frame flexibility

Brompton luggage

“Oh dear! That didn’t work!”, were my words for a little tweaking I was trying in my quest for the perfect luggage solution.

Robinson, my original (used) Brompton came with a C bag & by chance this bag also suits my second acquisition, Ralph, a flat bar S-type Brompton. Normally the C bag ought not to be used with the S model Bromptons (owing to bag handle clearance issues around the brake cables) but because Ralph has a set of Shimano brake levers, the brake cable angle raises the cable above the C bag handle & avoids any conflict.

Mrs Aussie’s Brompton, Peregrine, is a standard S model & we purchased an S bag for her use. With the arrival of Clarence (an S model again) there was likely to be a need for another S bag, this time for my use. However, it seemed a shame that the C bag couldn’t be used with Clarence, as the latest brake lever design seems to allow more cable clearance & the cables aren’t snagging enough to start applying the brakes when turning the handlebars?

Yes, I’ve seen some C bag hacks on the Internet, where the handle is cut off & maybe replaced with a strap or cord arrangement? Maybe I could do better? Maybe it just needed the handle to slope forward a little more & provide enough cable clearance? With the handle of the frame clamped in a vice, I tried a little flexing to see if the handle could be made to bend forward? After a bit more pressure I had my answer when the handle snapped off the frame! Oh dear, bother, etc… (apologies for no pics of the destruction – “too occupied”?)

The opportunity to fashion my own strap was “now available” & I started giving it some thought. Before long I had my resolution with a couple of large cable-ties & the original handle…
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Once the “Aussied” C bag was fitted to Clarence it seems an ideal solution, with the new handle being nicely flexible (& strong enough?) Will it work out? We shall see…
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